Keywords: drosophila

Transformation of meiotic drive into hybrid sterility in Drosophila

Jackson Bladen, Hyuck-Jin Nam, Nitin Phadnis,  bioRxiv,  2024.
Hybrid male sterility is one of the fastest evolving intrinsic reproductive barriers between recently isolated populations. A leading explanation for the evolution of hybrid male sterility involves genomic conflicts with meiotic drivers in the male germline. There are, however, ...
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The Wolbachia WalE1 effector alters Drosophila endocytosis

MaryAnn Martin,Sergio López-Madrigal,Irene L. G. Newton,  PLoS Pathogens,  20. 2024.
The most common intracellular bacterial infection is Wolbachia pipientis.
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Acetylcholine esterase of Drosophila melanogaster: a laboratory model to explore insecticide susceptibility gene drives

Hernandes, N., Qi, X.M., Bhide, S., Brown, C., Camm, B.J., Baxter, S.W. and Robin, C.,  Pest Management Science,  2024.
One of the proposed applications of gene drives has been to revert pesticide resistant mutations back to the ancestral susceptible state. Insecticides that have become ineffective because of the rise of resistance could have reinvigorated utility and be used to suppress pest ...
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The haplolethal gene wupA of Drosophila exhibits potential as a target for an X-poisoning gene drive

Lawler, Clancy D ,Parra Nuñez, Ana Karla ,Hernandes, Natalia ,Bhide, Soumitra ,Lohrey, Isabelle ,Baxter, Simon ,Robin, Charles,  G3 Genes Genome Genetics,  jkae025. 2024.
We examine this ‘X-poisoning’ strategy by targeting four of the 11 known X-linked haplolethal/haplosterile genes of Drosophila melanogaster with CRISPR/Cas9. We find that targeting the wupA gene during spermatogenesis skews the sex ratio so fewer than 14% of progeny are ...
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Use of Drosophila Transgenics to Identify Functions for Symbiont Effectors

Cortez, C.T., Murphy, R.O., Owens, I.M., Beckmann, J.F.,  Methods in Molecular Biology,  2739. 2023.
Wolbachia, one of the most successful and studied insect symbionts, and Drosophila, one of the most understood model insects, can be exploited as complementary tools to unravel mechanisms of insect symbiosis. Although Wolbachia itself cannot be grown axenically as clonal isolates ...
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Wolbachia endosymbionts manipulate the self-renewal and differentiation of germline stem cells to reinforce fertility of their fruit fly host

S. L. Russell, J. R. Castillo and W. T. Sullivan,  PLOS Biology,  21:e3002335. 2023.
The alphaproteobacterium Wolbachia pipientis infects arthropod and nematode species worldwide, making it a key target for host biological control. Wolbachia-driven host reproductive manipulations, such as cytoplasmic incompatibility (CI), are credited for catapulting these ...
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How mosquito-controlling bacteria might also enhance insect fertility

Public Library of Science,  Phys Org,  2023.
A new study reveals biological mechanisms by which a specific strain of bacteria in the Wolbachia genus might enhance the fertility of the insects it infects—with potentially important implications for mosquito-control strategies. Shelbi Russell of the University of California ...
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Wolbachia infection at least partially rescues the fertility and ovary defects of several new Drosophila melanogaster bag of marbles protein-coding mutants

M. Wenzel and C. F. Aquadro,  PLOS Genetics,  19:e1011009. 2023.
Author summary Reproduction in the Drosophila melanogaster fruit fly is dependent on the bag of marbles (bam) gene, which acts early in the process of generating eggs and sperm. Mutations to this gene negatively impact the fertility of the fly, causing it to be sterile or have ...
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Next-generation CRISPR gene-drive systems using Cas12a nuclease

S. Sanz Juste, E. M. Okamoto, C. Nguyen, X. Feng and V. López Del Amo,  Nature Communications,  14:6388. 2023.
One method for reducing the impact of vector-borne diseases is through the use of CRISPR-based gene drives, which manipulate insect populations due to their ability to rapidly propagate desired genetic traits into a target population. However, all current gene drives employ a ...
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Wolbachia enhances the survival ofDrosophila infected with fungal pathogens

J. Perlmutter, I., A. Atadurdyyeva, M. Schedl, E. and R. Unckless, L.,  bioRxiv,  2023.09.30.560320. 2023.
Wolbachia bacteria of arthropods are at the forefront of basic and translational research on multipartite host-symbiont-pathogen interactions. These microbes are vertically inherited from mother to offspring via the cytoplasm. They are the most widespread endosymbionts on the ...
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Testing a candidate meiotic drive locus identified by pool sequencing

D. A. Barbash, B. Jin, K. H. C. Wei and A.-M. Dion-Côté,  G3 Genes|Genomes|Genetics,  2023.
Meiotic drive biases the transmission of alleles in heterozygous individuals, such that Mendel’s law of equal segregation is violated. Most examples of meiotic drive have been discovered over the past century based on causing sex-ratio distortion or the biased transmission of ...
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Female meiotic drive shapes the distribution of rare inversion polymorphisms in Drosophila melanogaster

S. A. Koury,  Genetics,  2023.
In all species, new chromosomal inversions are constantly being formed by spontaneous rearrangement and then stochastically eliminated from natural populations. In Drosophila, when new chromosomal inversions overlap with a pre-existing inversion in the population, their rate of ...
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Wolbachia has subtle effects on thermal preference in highly inbred Drosophila melanogaster which vary with life stage and environmental conditions

A. Strunov, C. Schoenherr and M. Kapun,  Scientific Reports,  13:13792. 2023.
Temperature fluctuations are challenging for ectotherms which are not able to regulate body temperature by physiological means and thus have to adjust their thermal environment via behavior. However, little is yet known about whether microbial symbionts influence thermal ...
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Wolbachia infection at least partially rescues the fertility and ovary defects of several new Drosophila melanogaster bag of marbles protein-coding mutants

W. Miwa and F. A. Charles,  bioRxiv,  2023.03.20.532813. 2023.
The D. melanogaster protein coding gene bag of marbles (bam) plays a key role in early male and female reproduction by forming complexes with partner proteins to promote differentiation in gametogenesis. Like another germline gene, Sex lethal, bam genetically interacts with the ...
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Population suppression by release of insects carrying a dominant sterile homing gene drive targeting doublesex in Drosophila

C. Weizhe, G. Jialiang, L. Yiran and C. Jackson,  bioRxiv,  2023.07.17.549342. 2023.
Gene drive alleles, which bias their own inheritance and increase in frequency, show great promise for blocking disease transmission or directly suppressing pest populations. The most common engineered drive system is the CRISPR homing drive, which converts wild-type alleles to ...
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New germline Cas9 promoters show improved performance for homing gene drive

D. Jie, C. Weizhe, J. Xihua, X. Xuejiao, Y. Emily, Z. Ruizhi, Z. Yuqi, M. Matt, W. M. Philipp and C. Jackson,  bioRxiv,  2023.07.16.549205. 2023.
Gene drive systems could be a viable strategy to prevent pathogen transmission or suppress vector populations by propagating drive alleles with super-Mendelian inheritance. CRISPR-based homing gene drives, perhaps the most powerful gene drive strategy, convert wild type alleles ...
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The evolutionary history of Drosophila simulans Y chromosomes reveals molecular signatures of resistance to sex ratio meiotic drive

C. Courret, D. Ogereau, C. Gilbert, A. M. Larracuente and C. Montchamp-Moreau,  Mol Biol Evol,  2023.
The recent evolutionary history of the Y chromosome in Drosophila simulans, a worldwide species of Afrotropical origin, is closely linked to that of X-linked meiotic drivers (Paris system). The spread of the Paris drivers in natural populations has elicited the selection of drive ...
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Scientists are Gene-Editing Flies to Fight Crop Damage

E. Mullin,  WIRED,  2023.
In greenhouses in Oregon last month, researchers with the US Department of Agriculture began testing one such approach: sterilized male flies. The gene-edited bugs, made by St. Louis–based biotech company Agragene, are meant to suppress wild fly populations. The idea is that if ...
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The haplolethal gene wupA of Drosophila exhibits potential as a target for an X-poisoning gene drive

Lawler C., D. , Hernandes, N., Nunez, A. K. P., Bhide, S., Baxter, S. and Robin, C.,  bioRxiv,  2023.06.23.546292. 2023.
A synthetic gene drive that targets haplolethal genes on the X-chromosome can skew the sex ratio towards males. Like an X-shredder strategy it does not involve homing and that has advantages including the reduction in gene drive resistance allele formation. We examine this ...
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Regulatory logic of endogenous RNAi in silencing de novo genomic conflicts

J. Vedanayagam, C. J. Lin, R. Papareddy, M. Nodine, A. S. Flynt, J. Wen and E. C. Lai,  PLOS Genetics,  19:e1010787. 2023.
Although the biological utilities of endogenous RNAi (endo-RNAi) have been largely elusive, recent studies reveal its critical role in the non-model fruitfly Drosophila simulans to suppress selfish genes, whose unchecked activities can severely impair spermatogenesis. In ...
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CRISPR/Cas9-based split homing gene drive targeting doublesex for population suppression of the global fruit pest Drosophila suzukii

A. K. Yadav, C. Butler, A. Yamamoto, A. A. Patil, A. L. Lloyd and M. J. Scott,  Proc Natl Acad Sci U S A,  120:e2301525120. 2023.
Genetic-based methods offer environmentally friendly species-specific approaches for control of insect pests. One method, CRISPR homing gene drive that target genes essential for development, could provide very efficient and cost-effective control. While significant progress has ...
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To fight berry-busting fruit flies, researchers focus on sterilizing the bugs

M. Walling,  KTAL News.com,  2023.
Paul Nelson is used to doing battle with an invasive fruit fly called the spotted wing drosophila, a pest that one year ruined more than half the berries on the Minnesota farm he and his team run. In recent years, they’ve cut their losses closer to 5%, but it’s been ...
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CRISPR/Cas9-based gene drive could suppress agricultural pests

North Carolina State University,  Phys Org,  2023.
Researchers have developed a "homing gene drive system" based on CRISPR/Cas9 that could be used to suppress populations of Drosophila suzukii vinegar flies—so-called "spotted-wing Drosophila" that devastate soft-skinned fruit in North America, Europe and parts of South ...
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Essential and recurrent roles for hairpin RNAs in silencing de novo sex chromosome conflict in Drosophila simulans

J. Vedanayagam, M. Herbette, H. Mudgett, C. J. Lin, C. M. Lai, C. McDonough-Goldstein, S. Dorus, B. Loppin, C. Meiklejohn, R. Dubruille and E. C. Lai,  PLoS Biol,  21:e3002136. 2023.
Meiotic drive loci distort the normally equal segregation of alleles, which benefits their own transmission even in the face of severe fitness costs to their host organism. However, relatively little is known about the molecular identity of meiotic drivers, their strategies of ...
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Cell biology: Selfish B chromosomes unleashed by a dysfunctional chromosome segregation system

P. Ferree,  Current Biology,  33:R431-R434. 2023.
A study in the fruit fly Drosophila melanogaster shows that a defective chromosome segregation system allows non-essential B chromosomes to transmit at higher-than-Mendelian frequencies.
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Wolbachia protects Drosophila melanogaster against two naturally occurring and virulent viral pathogens

G. Bruner-Montero and F. M. Jiggins,  Scientific Reports,  13:8518. 2023.
Wolbachia is a common endosymbiont that can protect insects against viral pathogens. However, whether the antiviral effects of Wolbachia have a significant effect on fitness remains unclear. We have investigated the interaction between Drosophila melanogaster, Wolbachia and two ...
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Wolbachia genetically interacts with the bag of marbles germline stem cell gene in male D. melanogaster

M. Wenzel and C. F. Aquadro,  MicroPubl Biol,  2023.
The bacterial endosymbiont Wolbachia manipulates reproduction of its arthropod hosts to promote its own maternal vertical transmission. In female D. melanogaster , Wolbachia has been shown to genetically interact with three key reproductive genes ( bag of marbles ( bam ) , ...
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Combined actions of bacteriophage-encoded genes in Wolbachia-induced male lethality

H. Arai, H. Anbutsu, Y. Nishikawa, M. Kogawa, K. Ishii, M. Hosokawa, S. R. Lin, M. Ueda, M. Nakai, Y. Kunimi, T. Harumoto, D. Kageyama, H. Takeyama and M. N. Inoue,  iScience,  26:106842. 2023.
Some Wolbachia endosymbionts induce male killing, whereby male offspring of infected females are killed during development; however, the origin and diversity of the underlying mechanisms remain unclear. In this study, we identified a 76 kbp prophage region specific to ...
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B chromosomes reveal a female meiotic drive suppression system in Drosophila melanogaster

S. L. Hanlon and R. S. Hawley,  Current Biology,  2023.
Selfish genetic elements use a myriad of mechanisms to drive their inheritance and ensure their survival into the next generation, often at a fitness cost to its host.(1)(,)(2) Although the catalog of selfish genetic elements is rapidly growing, our understanding of host drive ...
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A male-killing Wolbachia endosymbiont is concealed by another endosymbiont and a nuclear suppressor

K. M. Richardson, P. A. Ross, B. S. Cooper, W. R. Conner, T. Schmidt and A. A. Hoffmann,  PLoS Biol,  21:e3001879. 2023.
Bacteria that live inside the cells of insect hosts (endosymbionts) can alter the reproduction of their hosts, including the killing of male offspring (male killing, MK). MK has only been described in a few insects, but this may reflect challenges in detecting MK rather than its ...
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Distinct Wolbachia localization patterns in oocytes of diverse host species reveal multiple strategies of maternal transmission

Y. A. Radousky, M. T. J. Hague, S. Fowler, E. Paneru, A. Codina, C. Rugamas, G. Hartzog, B. S. Cooper and W. Sullivan,  Genetics,  2023.
A broad array of endosymbionts radiate through host populations via vertical transmission, yet much remains unknown concerning the cellular basis, diversity and routes underlying this transmission strategy. Here we address these issues, by examining the cellular distributions of ...
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Assessing the hybridization potential between a hypothetical gene drive-modified Drosophila suzukii strain and non-target Drosophila species

J. Romeis, S. Wolf, J. Collatz, J. Enkerli and F. Widmer,  IOBC-WPRS Bulletin,  163:108. 2023.
Genetically engineered gene drives (GD) are a potentially powerful tool to control pest insects by population suppression or even elimination. Before living GD modified insects can be released into the environment, they must pass an environmental risk assessment (ERA). A key ...
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A male-killing gene encoded by a symbiotic virus of Drosophila

D. Kageyama, T. Harumoto, K. Nagamine, A. Fujiwara, T. N. Sugimoto, A. Jouraku, M. Tamura, T. K. Katoh and M. Watada,  Nature Communications,  14:1357. 2023.
In most eukaryotes, biparentally inherited nuclear genomes and maternally inherited cytoplasmic genomes have different evolutionary interests. Strongly female-biased sex ratios that are repeatedly observed in various arthropods often result from the male-specific lethality ...
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Effects of Wolbachia on Transposable Element Expression Vary Between Drosophila melanogaster Host Genotypes

A. T. Eugénio, M. S. P. Marialva and P. Beldade,  Genome Biology Evolution,  15. 2023.
Transposable elements (TEs) are repetitive DNA sequences capable of changing position in host genomes, thereby causing mutations. TE insertions typically have deleterious effects but they can also be beneficial. Increasing evidence of the contribution of TEs to adaptive evolution ...
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Ovarian Transcriptional Response to Wolbachia Infection in D. melanogaster in the Context of Between-Genotype Variation in Gene Expression

S. I. Frantz, C. M. Small, W. A. Cresko and N. D. Singh,  G3-Genes Genomes Genetics,  2023.
Wolbachia is a maternally-transmitted endosymbiotic bacteria that infects a wide variety of arthropod and nematode hosts. The effects of Wolbachia on host biology are far-reaching and include changes in host gene expression. However, previous work on the host transcriptional ...
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Next-generation CRISPR gene-drive systems using Cas12a nuclease

S. Sanz Juste, E. M. Okamoto, X. Feng and V. L. Del Amo,  bioRxiv,  2023.02.20.529271. 2023.
One method for reducing the impact of vector-borne diseases is through the use of CRISPR-based gene drives, which manipulate insect populations due to their ability to rapidly propagate desired genetic traits into a target population. However, all current gene drives employ a ...
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Next-generation CRISPR gene-drive systems using Cas12a nuclease

S. Sanz Juste, E. M. Okamoto, X. Feng and V. L. Del Amo,  bioRxiv,  2023.02.20.529271. 2023.
One method for reducing the impact of vector-borne diseases is through the use of CRISPR-based gene drives, which manipulate insect populations due to their ability to rapidly propagate desired genetic traits into a target population. However, all current gene drives employ a ...
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Expansion and loss of sperm nuclear basic protein genes in Drosophila correspond with genetic conflicts between sex chromosomes

C.-H. Chang, I. Mejia Natividad and H. S. Malik,  eLife,  12:e85249. 2023.
Many animal species employ sperm nuclear basic proteins (SNBPs) or protamines to package sperm genomes tightly. SNBPs vary across animal lineages and evolve rapidly in mammals. We used a phylogenomic approach to investigate SNBP diversification in Drosophila species. We found ...
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Expansion and loss of sperm nuclear basic protein genes in Drosophila correspond with genetic conflicts between sex chromosomes

C.-H. Chang, I. Mejia Natividad and H. S. Malik,  eLife,  12:e85249. 2023.
Many animal species employ sperm nuclear basic proteins (SNBPs) or protamines to package sperm genomes tightly. SNBPs vary across animal lineages and evolve rapidly in mammals. We used a phylogenomic approach to investigate SNBP diversification in Drosophila species. We found ...
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A selfish genetic element and its suppressor causes gross damage to testes in a fly

S. Lyth, A. Manser, G. Hurst, T. Price and R. Verspoor,  bioRxiv,  2023.02.06.527273. 2023.
Selfish genetic elements (SGEs), specifically X-chromosome meiotic drive (XCMD), create huge conflicts within a hosts genome and can have profound effects on fertility. Suppressors are a common evolutionary response to XCMD to negate its costs. However, whether suppressors ...
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Wolbachia Promotes Its Own Uptake by Host Cells

L. B. Nevalainen, E. M. Layton and I. L. G. Newton,  Infection and Immunity,  e0055722. 2023.
Wolbachia pipientis is an incredibly widespread bacterial symbiont of insects, present in an estimated 25 to 52% of species worldwide. Wolbachia is faithfully maternally transmitted both in a laboratory setting and in the wild. In an established infection, Wolbachia is primarily ...
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Genetic conversion of a split-drive into a full-drive element

G. Terradas, J. B. Bennett, Z. Li, J. M. Marshall and E. Bier,  Nature Communications,  14:191. 2023.
The core components of CRISPR-based gene drives, Cas9 and guide RNA (gRNA), either can be linked within a self-contained single cassette (full gene-drive, fGD) or be provided in two separate elements (split gene-drive, sGD), the latter offering greater control options. We ...
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Single-cell transcriptome sequencing reveals Wolbachia-mediated modification in early stages of Drosophila spermatogenesis

W. Dou, B. Sun, Y. Miao, D. Huang and J. Xiao,  Proceedings of the Royal Society B: Biological Sciences,  290:20221963. 2023.
Wolbachia are the most widely distributed intracellular bacteria, and their most common effect on host phenotype is cytoplasmic incompatibility (CI). A variety of models have been proposed to decipher the molecular mechanism of CI, among which the host modification (HM) model ...
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Single-cell transcriptome sequencing reveals Wolbachia-mediated modification in early stages of Drosophila spermatogenesis

W. Dou, B. Sun, Y. Miao, D. Huang and J. Xiao,  Proceedings of the Royal Society B: Biological Sciences,  290:20221963. 2023.
Wolbachia are the most widely distributed intracellular bacteria, and their most common effect on host phenotype is cytoplasmic incompatibility (CI). A variety of models have been proposed to decipher the molecular mechanism of CI, among which the host modification (HM) model ...
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Wolbachia endosymbionts manipulate GSC self-renewal and differentiation to enhance host fertility

S. L. Russell, J. R. Castillo and W. T. Sullivan,  bioRxiv,  2022.12.15.520626. 2022.
The alphaproteobacterium Wolbachia pipientis infects thousands of arthropod and nematode species worldwide, making it a key target for host biological control. Wolbachia-driven host reproductive manipulations, such as cytoplasmic incompatibility (CI), are often credited for ...
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Deregulation of Y-linked protamine-like genes in sex chromosome-biased spermatid demise

J. I. Park, G. W. Bell and Y. M. Yamashita,  bioRxiv,  2022.
Meiotic drive is a phenomenon wherein a genetic element achieves a higher rate of transmission than dictated by Mendelian segregation (1-3). One proposed mechanism for meiotic drivers to achieve biased transmission is by sabotaging essential processes of gametogenesis (e.g. ...
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Modeling-informed Engineered Genetic Incompatibility strategies to overcome resistance in the invasive Drosophila suzukii

A. Sychla, N. R. Feltman, W. D. Hutchison and M. J. Smanski,  Frontiers in Insect Science,  2. 2022.
Engineered Genetic Incompatibility (EGI) is an engineered extreme underdominance genetic system wherein hybrid animals are not viable, functioning as a synthetic speciation event. There are several strategies in which EGI could be leveraged for genetic biocontrol of pest ...
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Hidden endosymbionts: A male-killer concealed by another endosymbiont and a nuclear suppressor

K. M. Richardson, P. A. Ross, B. S. Cooper, W. R. Conner, T. Schmidt and A. A. Hoffmann,  bioRxiv,  2022.10.19.512817. 2022.
Maternally transmitted endosymbiotic bacteria that cause male killing (MK) have only been described from a few insects, but this may reflect challenges in their detection rather than a rarity of MK. Here we identify MK Wolbachia in populations of Drosophila pseudotakahashii, ...
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Mitotic exchange in female germline stem cells is the major source of Sex Ratio chromosome recombination in Drosophila pseudoobscura

S. Koury,  G3 Genes|Genomes|Genetics,  2022.
Sex Ratio chromosomes in Drosophila pseudoobscura are selfish X chromosome variants associated with three non-overlapping inversions. In the male germline, Sex Ratio chromosomes distort segregation of X and Y chromosomes (99:1), thereby skewing progeny sex ratio. In the female ...
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Fitness effects of CRISPR endonucleases in Drosophila melanogaster populations

A. M. Langmüller, J. Champer, S. Lapinska, L. Xie, M. Metzloff, S. E. Champer, J. Liu, Y. Xu, J. Du, A. G. Clark and P. W. Messer,  eLife,  11:e71809. 2022.
Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 provides a highly efficient and flexible genome editing technology with numerous potential applications ranging from gene therapy to population control. Some proposed applications involve the integration of ...
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Hoisted with his own petard: How sex-ratio meiotic drive in Drosophila affinis creates resistance alleles that limit its spread

W. J. Ma, E. M. Knoles, K. B. Patch, M. M. Shoaib and R. L. Unckless,  J Evol Biol,  2022.
Meiotic drivers are selfish genetic elements that tinker with gametogenesis to bias their own transmission into the next generation of offspring. Such tinkering can have significant consequences on gametogenesis and end up hampering the spread of the driver. In Drosophila ...
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CRISPR, an eco-friendly technology, may detect crop pests

W. Adam,  list23,  2022.
Drosophila suzukii, an invading insect pest, is a threat to agricultural yields, especially to the production of fruits such as strawberries, cherries, plums, and grapes in western countries. Until now, control measures to stop the spread of D. suzukii have been inadequate. A ...
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Comparative Ubiquitome Analysis Reveals Deubiquitinating Effects Induced by Wolbachia Infection in Drosophila melanogaster

Q. Zong, B. Mao, H. B. Zhang, B. Wang, W. J. Yu, Z. W. Wang and Y. F. Wang,  International Journal Molecular Science,  23. 2022.
The endosymbiotic Wolbachia bacteria frequently cause cytoplasmic incompatibility (CI) in their insect hosts, where Wolbachia-infected males cross with uninfected females, leading to no or fewer progenies, indicating a paternal modification by Wolbachia. Recent studies have ...
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Precision Guided Sterile Males Suppress Populations of an Invasive Crop Pest

N. P. Kandul, J. Liu, A. Buchman, I. C. Shriner, R. M. Corder, N. Warsinger-Pepe, T. Yang, A. K. Yadav, M. J. Scott, J. M. Marshall and O. S. Akbari,  GEN Biotechnology,  1:372-385. 2022.
The Drosophila suzukii invasion of western countries has created an immense agricultural and economic threat to crop production. Despite many attempts to suppress its population, D. suzukii continues to destroy soft-flesh fruits. Precision guided sterile insect technique (pgSIT) ...
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“Selfish Genetic Elements” – Supergene Wreaks Havoc in a Genome

University of Rochester,  SciTechDaily,  2022.
“Selfish genetic elements” litter the human genome. They do not seem to benefit their hosts but instead seek only to propagate themselves. These selfish genetic elements can wreak havoc. For example, they can distort sex ratios, impair fertility, cause harmful mutations, and ...
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What can we learn from selfish loci that break Mendel’s law?

S. E. Zanders,  PLOS Biology,  20:e3001700. 2022.
Mendel’s law of segregation provides a critical foundation for genetic inquiry It is not, however, without exceptions Historically, 2 such exceptions (sex chromosome linkage and chromosome missegregation in meiosis) were used by Drosophila geneticists to help demonstrate ...
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Hoisted with his own petard: how sex-ratio meiotic drive in <em>Drosophila affinis</em> creates resistance alleles that limit its spread

W.-J. Ma, E. M. Knoles, K. B. Patch, M. M. Shoaib and R. L. Unckless,  bioRxiv,  2022.02.14.480432. 2022.
Meiotic drivers are selfish genetic elements that tinker with gametogenesis to bias their own transmission into the next generation of offspring. Such tinkering can have significant consequences on gametogenesis and end up hampering the spread of the driver. In Drosophila ...
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Male-killing-associated bacteriophage WO identified from comparisons of Wolbachia endosymbionts of Homona magnanima

H. Arai, H. Anbutsu, Y. Nishikawa, M. Kogawa, K. Ishii, M. Hosokawa, S.-R. Lin, M. Ueda, M. Nakai, Y. Kunimi, T. Harumoto, D. Kageyama, H. Takeyama and M. N. Inoue,  bioRxiv,  2022.
The origin and mechanism of male-killing, an advantageous strategy employed by maternally transmitted symbionts such as Wolbachia, remain unclear. We compared genomes of four Wolbachia strains derived from Homona magnanima, a male-killing strain wHm-t (1.5 Mb), and three ...
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Mitotic exchange in female germline stem cells is the major source of Sex Ratio chromosome recombination in Drosophila pseudoobscura

S. Koury,  bioRxiv,  2022.06.07.495109. 2022.
Sex Ratio chromosomes in Drosophila pseudoobscura are selfish X chromosome variants associated with three non-overlapping inversions. In the male germline, Sex Ratio chromosomes distort segregation of X and Y chromosomes (99:1), thereby skewing progeny sex ratio. In the female ...
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A nickase Cas9 gene-drive system promotes super-Mendelian inheritance in Drosophila

V. L. Del Amo, S. S. Juste and V. M. Gantz,  Cell Rep,  39:110843. 2022.
CRISPR-based gene-drives have been proposed for managing insect populations, including disease-transmitting mosquitoes, due to their ability to bias their inheritance toward super-Mendelian rates (>50%). Current technologies use a Cas9 that introduces DNA double-strand breaks ...
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Experimental demonstration of tethered gene drive systems for confined population modification or suppression

M. Metzloff, E. Yang, S. Dhole, A. G. Clark, P. W. Messer and J. Champer,  BMC Biol,  20:119. 2022.
BACKGROUND: Homing gene drives hold great promise for the genetic control of natural populations. However, current homing systems are capable of spreading uncontrollably between populations connected by even marginal levels of migration. This could represent a substantial ...
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Intronic gRNAs for the Construction of Minimal Gene Drive Systems

A. Nash, P. Capriotti, A. Hoermann, P. A. Papathanos and N. Windbichler,  Frontiers in Bioengineering and Biotechnology,  10. 2022.
Gene drives are promising tools for the genetic control of insect vector or pest populations. CRISPR-based gene drives are generally highly complex synthetic constructs consisting of multiple transgenes and their respective regulatory elements. This complicates the generation of ...
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The fate of a suppressed X-linked meiotic driver: experimental evolution in Drosophila simulans

H. Bastide, D. Ogereau, C. Montchamp-Moreau and P. R. Gérard,  Chromosome Research,  2022.
Sex-ratio (SR) meiotic drivers are X-linked selfish genetic elements that promote their own transmission by preventing the production of Y-bearing sperm, which usually lowers male fertility. The spread of SR drivers in populations is expected to trigger the evolution of unlinked ...
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Experimental demonstration of tethered gene drive systems for confined population modification or suppression

M. Metzloff, E. Yang, S. Dhole, A. G. Clark, P. W. Messer and J. Champer,  bioRxiv,  2021.05.29.446308. 2022.
Homing gene drives hold great promise for the genetic control of natural populations. However, current homing systems are capable of spreading uncontrollably between populations connected by even marginal levels of migration. This could represent a substantial sociopolitical ...
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A homing suppression gene drive with multiplexed gRNAs maintains high drive conversion efficiency and avoids functional resistance alleles

E. Yang, M. Metzloff, A. M. Langmuller, X. J. Xu, A. G. Clark, P. W. Messer and J. Champer,  G3-Genes Genomes Genetics,  13. 2022.
Gene drives are engineered alleles that can bias inheritance in their favor, allowing them to spread throughout a population. They could potentially be used to modify or suppress pest populations, such as mosquitoes that spread diseases. CRISPR/Cas9 homing drives, which copy ...
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A homing suppression gene drive with multiplexed gRNAs maintains high drive conversion efficiency and avoids functional resistance alleles

E. Yang, M. Metzloff, A. M. Langmüller, X. Xu, A. G. Clark, P. W. Messer and J. Champer,  bioRxiv,  2021.05.27.446071. 2022.
Gene drives are engineered alleles that can bias inheritance in their favor, allowing them to spread throughout a population. They could potentially be used to modify or suppress pest populations, such as mosquitoes that spread diseases. CRISPR/Cas9 homing drives, which copy ...
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Evaluation of Additional Drosophila suzukii Male-Only Strains Generated Through Remobilization of an FL19 Transgene

A. Yamamoto, A. K. Yadav and M. J. Scott,  Frontiers in Bioengineering and Biotechnology,  10. 2022.
Drosophila suzukii (D. suzukii) (Matsumura, 1931; Diptera: Drosophilidae), also known as spotted wing Drosophila, is a worldwide pest of fruits with soft skins such as blueberries and cherries. Originally from Asia, D. suzukii is now present in the Americas and Europe and has ...
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Hoisted with his own petard: how sex-ratio meiotic drive in Drosophila affnis creates resistance alleles that limit its spread

W.-J. Ma, K. B. Patch, E. M. Knoles, M. M. Shoaib and R. L. Unckless,  bioRxiv,  2022.02.14.480432. 2022.
Meiotic drivers are selfish genetic elements that tinker with gameto-genesis to bias their own transmission into the next generation of off-spring. Such tinkering can have significant consequences on gameto-genesis and end up hampering the spread of the driver. In Drosophila ...
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Endosymbionts moderate constrained sex allocation in a haplodiploid thrips species in a temperature-sensitive way

A. Katlav, D. T. Nguyen, J. L. Morrow, R. N. Spooner-Hart and M. Riegler,  Heredity,  9. 2022.
Maternally inherited bacterial endosymbionts that affect host fitness are common in nature. Some endosymbionts colonise host populations by reproductive manipulations (such as cytoplasmic incompatibility; CI) that increase the reproductive fitness of infected over uninfected ...
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Could Crispr Flip the Switch on Insects’ Resistance to Pesticides?

E. Mullin,  WIRED,  2022.
WHILE THE COVID-19 pandemic raged across the world in 2020, another disease was quietly infecting more than 220 million people on the continent of Africa: malaria. That year, the disease led to more than 600,000 deaths, most of them children. Caused by the parasite Plasmodium, ...
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Genetically engineered insects with sex-selection and genetic incompatibility enable population suppression

A. Upadhyay, N. R. Feltman, A. Sychla, A. Janzen, S. R. Das, M. Maselko and M. Smanski,  eLife,  11. 2022.
Engineered Genetic Incompatibility (EGI) is a method to create species-like barriers to sexual reproduction. It has applications in pest control that mimic Sterile Insect Technique when only EGI males are released. This can be facilitated by introducing conditional ...
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Paternal transmission of the Wolbachia CidB toxin underlies cytoplasmic incompatibility

B. Horard, K. Terretaz, A. S. Gosselin-Grenet, H. Sobry, M. Sicard, F. Landmann and B. Loppin,  Current Biology,  2022.
Wolbachia are widespread endosymbiotic bacteria that manipulate the reproduction of arthropods through a diversity of cellular mechanisms. In cytoplasmic incompatibility (CI), a sterility syndrome originally discovered in the mosquito Culex pipiens, uninfected eggs fertilized by ...
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Genetic Strategy Reverses Insecticide Resistance

H. Tasoff,  The Current,  2022.
University of California biologists have now developed a method that reverses insecticide resistance using CRISPR/Cas9 technology. A team including UC Santa Barbara researchers Craig Montell(link is external) and Menglin Li(link is external), UC San Diego researchers Bhagyashree ...
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Stakeholder engagement to inform the risk assessment and governance of gene drive technology to manage spotted-wing drosophila

A. E. Kokotovich, S. K. Barnhill-Dilling, J. E. Elsensohn, R. Li, J. A. Delborne and H. Burrack,  Journal of Environmental Management,  307:114480. 2022.
Emerging biotechnologies, such as gene drive technology, are increasingly being proposed to manage a variety of pests and invasive species. As one method of genetic biocontrol, gene drive technology is currently being developed to manage the invasive agricultural pest ...
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Genetic conversion of a split-drive into a full-drive element

G. Terradas, J. B. Bennett, Z. Li, J. M. Marshall and E. Bier,  bioRxiv,  2021.12.05.471291. 2021.
Gene-drive systems offer an important new avenue for spreading beneficial traits into wild populations. Their core components, Cas9 and guide RNA (gRNA), can either be linked within a single cassette (full gene drive, fGD) or provided in two separate elements (split gene drive, ...
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Nuclear transport genes recurrently duplicate by means of RNA intermediates in Drosophila but not in other insects

A. Mirsalehi, D. N. Markova, M. Eslamieh and E. Betrán,  BMC Genomics,  22:876. 2021.
We find that most of the nuclear transport duplications in Drosophila are of a few classes of nuclear transport genes, RNA mediated and fast evolving. We also retrieve many pseudogenes for the Ran gene. Some of the duplicates are relatively young and likely contributing to the ...
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Rapid evolutionary dynamics of an expanding family of meiotic drive factors and their hpRNA suppressors

J. Vedanayagam, C. J. Lin and E. C. Lai,  Nature Ecology and Evolution,  2021.
Meiotic drivers are a class of selfish genetic elements whose existence is frequently hidden due to concomitant suppressor systems. Accordingly, we know little of their evolutionary breadth and molecular mechanisms. Here, we trace the evolution of the Dox meiotic drive system in ...
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CRISPR gene-drive systems based on Cas9 nickases promote super-Mendelian inheritance in Drosophila

V. Lopez del Amo, S. Sanz Juste and V. M. Gantz,  bioRxiv,  2021.12.01.470847. 2021.
CRISPR-based gene drive systems can be used to modify entire wild populations due to their ability to bias their own inheritance towards super-Mendelian rates (&gt;100%). Current gene drives contain a Cas9 and a gRNA gene inserted at the location targeted by the gRNA. These ...
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Gene drive that results in addiction to a temperature-sensitive version of an essential gene triggers population collapse in Drosophila

G. Oberhofer, T. Ivy and B. A. Hay,  Proceedings of the National Academy of Sciences,  118:e2107413118. 2021.
One strategy for population suppression seeks to use gene drive to spread genes that confer conditional lethality or sterility, providing a way of combining population modification with suppression. Stimuli of potential interest could be introduced by humans, such as an otherwise ...
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Wolbachia reduces virus infection in a natural population of Drosophila

R. Cogni, S. D. Ding, A. C. Pimentel, J. P. Day and F. M. Jiggins,  Communications Biology,  4:1327. 2021.
Wolbachia is a maternally transmitted bacterial symbiont that is estimated to infect approximately half of arthropod species. In the laboratory it can increase the resistance of insects to viral infection, but its effect on viruses in nature is unknown. Here we report that in a ...
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Temperature-Inducible Precision-Guided Sterile Insect Technique

N. P. Kandul, J. R. Liu and O. S. Akbari,  CRISPR Journal,  14. 2021.
Releases of sterile males are the gold standard for many insect population control programs, and precise sex sorting to remove females prior to male releases is essential to the success of these operations. To advance traditional methods for scaling the generation of sterile ...
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Centromere function in asymmetric cell division in Drosophila female and male germline stem cells

A. M. Kochendoerfer, F. Modafferi and E. M. Dunleavy,  Open Biology,  11:210107. 2021.
The centromere is the constricted chromosomal region required for the correct separation of the genetic material at cell division. The kinetochore protein complex assembles at the centromere and captures microtubules emanating from the centrosome to orchestrate chromosome ...
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Ecological vulnerability analysis for suppression of Drosophila suzukii by gene drives

C. R. Lalyer, L. Sigsgaard and B. Giese,  Global Ecology and Conservation,  32:e01883. 2021.
Synthetic gene drives are transgenic constructs that aim to bias heredity and thereby influence the characteristics and fate of populations regarding abundance and evolution. Aside from irreversible effects in ecosystems that could be triggered by the release of a gene drive, ...
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Sexual selection can partly explain low frequencies of Segregation Distorter alleles

T. A. Keaney, T. M. Jones and L. Holman,  Proceedings of the Royal Society B: Biological Sciences,  288:20211190. 2021.
The Segregation Distorter (SD) allele found in Drosophila melanogaster distorts Mendelian inheritance in heterozygous males by causing developmental failure of non-SD spermatids, such that greater than 90% of the surviving sperm carry SD. This within-individual advantage should ...
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Wolbachia-Conferred Antiviral Protection Is Determined by Developmental Temperature

E. Chrostek, N. Martins, M. S. Marialva and L. Teixeira,  mBio,  e0292320. 2021.
Overall, we show that Wolbachia-conferred antiviral protection is temperature dependent, being present or absent depending on the environmental conditions. This interaction likely impacts Wolbachia-host interactions in nature and, as a result, frequencies of host and symbionts in ...
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Diverse wMel variants of Wolbachia pipientis differentially rescue fertility and cytological defects of the bag of marbles partial loss of function mutation in Drosophila melanogaster

J. E. Bubnell, P. Fernandez-Begne, C. K. S. Ulbing and C. F. Aquadro,  G3 Genes|Genomes|Genetics,  2021.
In Drosophila melanogaster, the maternally inherited endosymbiont Wolbachia pipientis interacts with germline stem cell genes during oogenesis. One such gene, bag of marbles (bam) is the key switch for differentiation and also shows signals of adaptive evolution for protein ...
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Satellite DNA-mediated diversification of a sex-ratio meiotic drive gene family in Drosophila

C. A. Muirhead and D. C. Presgraves,  Nature Ecology & Evolution,  2021.
Sex chromosomes are susceptible to the evolution of selfish meiotic drive elements that bias transmission and distort progeny sex ratios. Conflict between such sex-ratio drivers and the rest of the genome can trigger evolutionary arms races resulting in genetically suppressed ...
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Red queen’s race: rapid evolutionary dynamics of an expanding family of meiotic drive factors and their hpRNA suppressors

J. Vedanayagam, C.-J. Lin and E. C. Lai,  bioRxiv,  2021.08.05.454923. 2021.
Meiotic drivers are a class of selfish genetic elements that are widespread across eukaryotes. Their activities are often detrimental to organismal fitness and thus trigger drive suppression to ensure fair segregation during meiosis. Accordingly, their existence is frequently ...
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A transgenic female killing system for the genetic control of Drosophila suzukii

M. F. Schetelig, J. Schwirz and Y. Yan,  Scientific Reports,  11:12938. 2021.
The spotted wing Drosophila (Drosophila suzukii) is an invasive pest of soft-skinned fruit crops. It is rapidly transmitted in Europe and North America, causing widespread agricultural losses. Genetic control strategies such as the sterile insect technique (SIT) have been ...
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Experimental demonstration of tethered gene drive systems for confined population modification or suppression

M. Metzloff, E. Yang, S. Dhole, A. G. Clark, P. W. Messer and J. Champer,  bioRxiv,  2021.05.29.446308. 2021.
Tethered drive systems, in which a locally confined gene drive provides the CRISPR nuclease needed for a homing drive, could provide a solution to this problem, offering the power of a homing drive and confinement of the supporting drive. Here, we demonstrate the engineering of a ...
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A homing suppression gene drive with multiplexed gRNAs maintains high drive conversion efficiency and avoids functional resistance alleles

E. Yang, M. Metzloff, A. M. Langmüller, A. G. Clark, P. W. Messer and J. Champer,  bioRxiv,  2021.05.27.446071. 2021.
Gene drives are engineered alleles that can bias inheritance in their favor, allowing them to spread throughout a population. They could potentially be used to modify or suppress pest populations, such as mosquitoes that spread diseases. CRISPR/Cas9 homing drives, which copy ...
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Pest reduction with female killers and sterile males

L. Mertz,  Good Fruit Grower,  2021.
New ways to fight spotted wing drosophila are in the works, thanks to new genetic engineering tools. These transgenic methods introduce new reproduction-hampering genes into male SWD, so that when they mate with females, the females either don’t have any young, or their female ...
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New genetic copycatchers detect efficient and precise CRISPR editing in a living organism

UNIVERSITY OF CALIFORNIA - SAN DIEGO,  UNIVERSITY OF CALIFORNIA - SAN DIEGO,  2021.
Researchers at the University of California San Diego have laid the groundwork for a potential new type of gene therapy using novel CRISPR-based techniques. Working in fruit flies and human cells, research led by UC San Diego Postdoctoral Scholar Zhiqian Li in Division of ...
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CopyCatchers are versatile active genetic elements that detect and quantify inter-homolog somatic gene conversion

Z. Li, N. Marcel, S. Devkota, A. Auradkar, S. M. Hedrick, V. M. Gantz and E. Bier,  Nature Communications,  12:2625. 2021.
CRISPR-based active genetic elements, or gene-drives, copied via homology-directed repair (HDR) in the germline, are transmitted to progeny at super-Mendelian frequencies. Active genetic elements also can generate widespread somatic mutations, but the genetic basis for such ...
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Inherently confinable split-drive systems in Drosophila

G. Terradas, A. B. Buchman, J. B. Bennett, I. Shriner, J. M. Marshall, O. S. Akbari and E. Bier,  Nature Communications,  12:1480. 2021.
CRISPR-based gene-drive systems, which copy themselves via gene conversion mediated by the homology-directed repair (HDR) pathway, have the potential to revolutionize vector control. However, mutant alleles generated by the competing non-homologous end-joining (NHEJ) pathway, ...
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A confinable home and rescue gene drive for population modification

N. P. Kandul, J. Liu, J. B. Bennett, J. M. Marshall and O. S. Akbari,  eLife,  10:e65939. 2021.
Homing based gene drives, engineered using CRISPR/Cas9, have been proposed to spread desirable genes throughout populations. However, invasion of such drives can be hindered by the accumulation of resistant alleles. To limit this obstacle, we engineer a confinable population ...
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Edit, undo: Temporary gene editing could help solve the mosquito problem

L. Dormehl,  digitaltrends,  2020.
But if SyFy original movies have taught us anything, it’s that genetically tweaking organisms and then releasing them can… well, not go quite according to plan.With that in mind, a new Texas A&M AgriLife Research project seeks to test out genetic modifications of mosquitos ...
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Fruit fly breakthrough puts killer mozzies on notice

V. Tressider,  The Lighthouse,  2020.
A new designer fruit fly paves the way for scientists to replace disease-carrying mosquitoes with harmless, genetically modified versions, says Macquarie University researcher Dr Maciej Maselko.
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Engineering multiple species-like genetic incompatibilities in insects

M. Maselko, N. Feltman, A. Upadhyay, A. Hayward, S. Das, N. Myslicki, A. J. Peterson, M. B. O’Connor and M. J. Smanski,  Nature Communications,  11:4468. 2020.
Here, we demonstrate a general approach to create engineered genetic incompatibilities (EGIs) in the model insect Drosophila melanogaster.
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Inherently confinable split-drive systems in Drosophila

G. Terradas, A. B. Buchman, J. B. Bennett, I. Shriner, J. M. Marshall, O. S. Akbari and E. Bier,  bioRxiv,  2020.09.03.282079. 2020.
Here, we test split gene-drive (sGD) systems in Drosophila melanogaster that were inserted into essential genes required for viability (rab5, rab11, prosalpha2) or fertility (spo11). I
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A home and rescue gene drive forces its inheritance stably persisting in populations

N. P. Kandul, J. Liu, J. B. Bennett, J. M. Marshall and O. Akbari,  bioRxiv,  2020.08.21.261610. 2020.
We demonstrate that HomeR can achieve nearly ~100% transmission enabling it to persist at genotypic fixation in several multi-generational population cage experiments, underscoring its long term stability.
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Engineered Reproductively Isolated Species Drive Reversible Population Replacement

A. Buchman, I. Shriner, T. Yang, J. Liu, I. Antoshechkin, J. M. Marshall, M. W. Perry and O. S. Akbari,  bioRxiv,  2020.08.09.242982. 2020.
Engineered reproductive species barriers are useful for impeding gene flow and driving desirable genes into wild populations in a reversible threshold-dependent manner. We engineer multiple reproductively isolated SPECIES and demonstrate their threshold-dependent gene drive ...
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CRISPR gene drives could eliminate many vector-driven pests and diseases, but challenges remain

J. Champer,  Genetic Literacy Project,  2020.
A functioning gene drive system could fundamentally change our strategies for the control of vector-borne diseases by facilitating rapid dissemination of transgenes that prevent pathogen transmission or reduce vector capacity. CRISPR/Cas9 gene drive promises such a mechanism, ...
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Extensive Recombination Suppression and Epistatic Selection Causes Chromosome-Wide Differentiation of a Selfish Sex Chromosome in Drosophila pseudoobscura

Z. L. Fuller, S. A. Koury, C. J. Leonard, R. E. Young, K. Ikegami, J. Westlake, S. Richards, S. W. Schaeffer and N. Phadnis,  Genetics,  216:205. 2020.
Here, we conduct a multifaceted study of the multiply inverted Drosophila pseudoobscura SR chromosome to understand the evolutionary history, genetic architecture, and present-day dynamics that shape this enigmatic selfish chromosome.
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Chemical controllable gene drive in Drosophila

D. Chae, J. Lee, N. Lee, K. Park, S. J. Moon and H. H. Kim,  ACS Synthetic Biology,  in press. 2020.
Here, we report a chemical-induced control of gene drive. We prepared a CRISPR-based gene drive system that can be removed by a site-specific recombinase, Rippase, the expression of which is induced by the chemical RU486 in fruit flies. Exposure of fruit flies to RU486 resulted ...
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Nix alone is sufficient to convert female Aedes aegypti into fertile males and myo-sex is needed for male flight

A. Aryan, M. A. E. Anderson, J. K. Biedler, Y. M. Qi, J. M. Overcash, A. N. Naumenko, M. V. Sharakhova, C. H. Mao, Z. N. Adelman and Z. J. Tu,  Proceedings of the National Academy of Sciences of the United States of America,  117:17702-17709. 2020.
Here, we report the generation of multiple transgenic lines that express Nix under the control of its own promoter. Genetic and molecular analyses of these lines provided insights unattainable from previous transient experiments. We show that the Nix transgene alone, in the ...
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Analysis of a Strong Suppressor of Segregation Distorter inDrosophila melanogaster

R. G. Temin,  Genetics,  215:1085-1105. 2020.
These studies highlight the polygenic nature of distortion and its dependence on a constellation of positive and negative modifiers, provide insight into the stability of Mendelian transmission in natural populations even when a drive system arises, and pave the way for molecular ...
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Development and testing of a novel killer–rescue self-limiting gene drive system in Drosophila melanogaster

S. H. Webster, M. R. Vella and M. J. Scott,  Proceedings of the Royal Society B: Biological Sciences,  287:20192994. 2020.
Here we report the development and testing of a novel self-limiting gene drive system, Killer–Rescue (K–R), in Drosophila melanogaster. This system is composed of an autoregulated Gal4 Killer (K) and a Gal4-activated Gal80 Rescue (R). Overexpression of Gal4 is lethal, but in ...
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Engineering multiple species-like genetic incompatibilities in insects

M. Maselko, N. Feltman, A. Upadhyay, A. Hayward, S. Das, N. Myslicki, A. J. Peterson, M. B. O’Connor and M. J. Smanski,  bioRxiv,  2020.
Speciation constrains the flow of genetic information between populations of sexually reproducing organisms. Gaining control over mechanisms of speciation would enable new strategies to manage wild populations of disease vectors, agricultural pests, and invasive species. ...
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Gene drive and resilience through renewal with next generation Cleave and Rescue selfish genetic elements

G. Oberhofer, T. Ivy and B. A. Hay,  Proceedings of the National Academy of Sciences,  117:9013-9021. 2020.
Gene drive can spread beneficial traits through populations, but will never be a one-shot project in which one genetic element provides all desired modifications, for an indefinitely long time. Here, we show that gene drive-mediated population modification in Drosophila can be ...
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Engineering a minimal gene drive system for integral replacement in Drosophila melanogaster

A. Nash,  Imperial College London,  2020.
Gene drives represent a powerful tool for the control of vector-borne diseases. By suppressing or replacing vector populations, laboratory studies have highlighted the potential for this group of tools to make a powerful impact on the burden of zoonotic disease. Current genetic ...
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A fly model establishes distinct mechanisms for synthetic CRISPR/Cas9 sex distorters

B. Fasulo, A. Meccariello, M. Morgan, C. Borufka, P. A. Papathanos and N. Windbichler,  PLOS Genetics,  16:e1008647. 2020.
Author summary Harmful insect populations can be eliminated for a lack of females if they are made to produce mostly male offspring. There are genes that occur naturally that make males produce mostly sons and, although we don’t know exactly how they work, this appears to ...
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Genetic Variation and Potential for Resistance Development to the tTA Overexpression Lethal System in Insects

K. E. Knudsen, W. R. Reid, T. M. Barbour, L. M. Bowes, J. Duncan, E. Philpott, S. Potter and M. J. Scott,  G3: Genes|Genomes|Genetics,  Early Online:g3.400990.2020. 2020.
Release of insect pests carrying the dominant lethal tetracycline transactivator (tTA) overexpression system has been proposed as a means for population suppression. High levels of the tTA transcription factor are thought to be toxic due to either transcriptional squelching or ...
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Autosomal suppression and fitness costs of an old driving X chromosome in Drosophila testacea

G. Keais, S. Lu and S. Perlman,  Journal of Evolutionary Biology,  2020.
Driving X chromosomes (XDs) are meiotic drivers that bias their own transmission through males by killing Y-bearing gametes. These chromosomes can in theory spread rapidly in populations and cause extinction, but many are found as balanced polymorphisms or as ?cryptic? XDs shut ...
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Mass-Rearing of Drosophila suzukii for Sterile Insect Technique Application: Evaluation of Two Oviposition Systems

F. Sassù, K. Nikolouli, S. Caravantes, G. Taret, R. Pereira, M. J. B. Vreysen, C. Stauffer and C. Cáceres,  Insects,  10. 2019.
Drosophila suzukii (Diptera: Drosophilidae) is an invasive pest of a wide range of commercial soft-skinned fruits. To date, most management tactics are based on spraying of conventional and/or organic insecticides, baited traps, and netting exclusion. Interest has been expressed ...
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Sex-ratio meiotic drive shapes the evolution of the Y chromosome in Drosophila simulans

Q. Helleu, C. Courret, D. Ogereau, K. L. Burnham, N. Chaminade, M. Chakir, S. Aulard and C. Montchamp-Moreau,  Molecular Biology and Evolution,  36:2668-2681. 2019.
The recent emergence and spread of X-linked segregation distorters-called "Paris" system-in the worldwide species Drosophila simulans has elicited the selection of drive-resistant Y chromosomes. Here, we investigate the evolutionary history of 386 Y chromosomes originating from ...
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CRISPR gene drive efficiency and resistance rate is highly heritable with no common genetic loci of large effect

Champer, JW, Z. X.; Luthra, A.; Reeves, R.; Chung, J.; Liu, C.; Lee, Y. L.; Liu, J. X.; Yang, E.; Messer, P. W.; Clark, A. G.,  Genetics,  212:333-341. 2019.
Gene drives could allow for control of vector-borne diseases by directly suppressing vector populations or spreading genetic payloads designed to reduce pathogen transmission. Clustered regularly interspaced short palindromic repeat (CRISPR) homing gene drives work by cleaving ...
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Multiplexing gRNAs to Hedge Against Resistance to Gene Drive

Travis Van Warmerdam,  IGTRCN,  2018.
Recently, Oberhofer et al (2018) published a paper examining the mechanisms of homing endonuclease gene drives in The Proceedings of the National Academy of Sciences. They used a novel nuclease-encoding cassette containing four multiplexed gRNAs targeting genes required for ...
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Rapid comeback of males: evolution of male-killer suppression in a green lacewing population

Hayashi, MN, M.; Kageyama, D.,  Proceedings of the Royal Society B-Biological Sciences,  285:6. 2018.
Evolutionary theory predicts that the spread of cytoplasmic sex ratio distorters leads to the evolution of host nuclear suppressors, although there are extremely few empirical observations of this phenomenon. Here, we demonstrate that a nuclear suppressor of a cytoplasmic male ...
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Cas9-triggered chain ablation of cas9 as a gene drive brake

Wu, BL, L. Q.; Gao, X. J. J.,  Nature Biotechnology,  34:137-138. 2016.
We designed and synthesized a transgene system that we named Cas9-triggered chain ablation (CATCHA). The CATCHA transgene encodes a guide RNA (gRNA) that is expressed ubiquitously from a U6:2 promoter. The gRNA targets a site within the DNA sequence of cas9. The guide RNA is ...
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Requirements for effective malaria control with homing endonuclease genes

Deredec, AG, H. C. J.; Burt, A.,  Proceedings of the National Academy of Sciences of the United States of America,  108:e874-e880. 2011.
Malaria continues to impose a substantial burden on human health. We have previously proposed that biological approaches to control the mosquito vector of disease could be developed using homing endonuclease genes (HEGs), a class of selfish or parasitic gene that exists naturally ...
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Mariner transposition and transformation of the yellow fever mosquito, Aedes aegypti

C. J. Coates, N. Jasinskiene, L. Miyashiro and A. A. James,  Proceedings of the National Academy of Sciences of the United States of America,  95:3748-3751. 1998.
The mariner transposable element is capable of interplasmid transposition in the embryonic soma of the yellow fever mosquito, Aedes aegypti. To determine if this demonstrated mobility could be utilized to genetically transform the mosquito, a modified mariner element marked with ...
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Stable transformation of the yellow fever mosquito, Aedes aegypti, with the Hermes element from the housefly

N. Jasinskiene, C. J. Coates, M. Q. Benedict, A. J. Cornel, C. S. Rafferty, A. A. James and F. H. Collins,  Proceedings of the National Academy of Sciences of the United States of America,  95:3743-3747. 1998.
The mosquito Aedes aegypti is the world's most important vector of yellow fever and dengue viruses, Work is currently in progress to control the transmission of these viruses by genetically altering the capacity of wild Ae, aegypti populations to support virus replication. The ...
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Genetic-transformation of Drosophila with transposable element vectors

G. M. Rubin and A. C. Spradling,  Science,  218:348-353. 1982.
Exogenous DNA sequences were introduced into the Drosophila germ line. A rosy transposon (ry1), constructed by inserting a chromosomal DNA fragment containing the wild-type rosy gene into a P transposable element, transformed germ line cells in 20 to 50 percent of the injected ...
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Genetic control of insect populations: I. Cage studies of chromosome replacement by compound autosomes in Drosophila melanogaste

M. Fitz-Earle, D. G. Holm and D. T. Suzuki,  Genetics,  74:461-475. 1973.
A genetic method for insect control was evaluated using the test organism, Drosophila melanogaster. The technique involved the displacement under a system of continuous reproduction, of standard strains by those carrying compound autosomes. The eradication of the replacements ...
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