Keywords: plants

Benefits and risks of gene drives for invasive plant management – the case for common tansy

L. Croghan, A. G. Smith, M. A. Tancos, N. O. Anderson and R. L. Becker,  Frontiers in Agronomy,  5. 2023.
Invasive plants cause significant environmental and economic damage, but land managers have few control options. Common tansy (Tanacetum vulgare) is prevalent in many US states and is one of the most reported invasive plants in Minnesota. Controlling common tansy poses a ...
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Gene drive in plants emerges from infancy

M. J. A. Awan, R. Z. Naqvi, I. Amin and S. Mansoor,  Trends in Plant Science,  2023.
Selfish genetic elements (SGEs) display biased transmission to offspring. However, their breeding potential has remained obscure. Wang et al. recently reported a natural gene-drive system that can be harnessed to prevent hybrid incompatibility and to develop a synthetic ...
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Cleave and Rescue gamete killers create conditions for gene drive in plants

O. Georg, L. J. Michelle, I. Tobin and A. H. Bruce,  bioRxiv,  2023.10.13.562303. 2023.
Gene drive elements promote the spread of linked traits, even when their presence confers a fitness cost to carriers, and can be used to change the composition or fate of wild populations. Cleave and Rescue (ClvR) drive elements sit at a fixed chromosomal position and include a ...
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Overriding Mendelian inheritance in Arabidopsis with a CRISPR toxin-antidote gene drive that impairs pollen germination

L. Yang, J. Bingke, C. Jackson and Q. Wenfeng,  bioRxiv,  2023.10.10.561637. 2023.
Synthetic gene drives, inspired by natural selfish genetic elements, present transformative potential for disseminating traits that benefit humans throughout wild populations, irrespective of potential fitness costs. Here, we constructed a gene drive system called CRISPR-Assisted ...
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A natural gene drive element confers speciation in rice

Y. Li, S. Liu and R. Shen,  Chinese Science Bulletin,  68:3400-3402. 2023.
For a long time, although many important advances have been made in the field of rice hybrid sterility, the specific molecular mechanism behind the "killer-protector"/ "poison-antidote" model has been unclear. Recently, the team of Academician Wan Jianmin of Nanjing Agricultural ...
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Using Wolbachia to control rice planthopper populations: progress and challenges

Y. Guo, J. Shao, Y. Wu and Y. Li,  Frontiers in Microbiology,  14. 2023.
Wolbachia have been developed as a tool for protecting humans from mosquito populations and mosquito-borne diseases. The success of using Wolbachia relies on the facts that Wolbachia are maternally transmitted and that Wolbachia-induced cytoplasmic incompatibility provides a ...
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The role of conflict in shaping plant biodiversity

J. M. Coughlan,  New Phytologist,  2023.
Although intrinsic postzygotic reproductive barriers can play a fundamental role in speciation, their underlying evolutionary causes are widely debated. One hypothesis is that incompatibilities result from genomic conflicts. Here, I synthesize the evidence that conflict generates ...
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Meiotic segregation and post-meiotic drive of the Festuca pratensis B chromosome

R. Ebrahimzadegan, J. Fuchs, J. Chen, V. Schubert, A. Meister, A. Houben and G. Mirzaghaderi,  Chromosome Research,  31:26. 2023.
In many species, the transmission of B chromosomes (Bs) does not follow the Mendelian laws of equal segregation and independent assortment. This deviation results in transmission rates of Bs higher than 0.5, a process known as “chromosome drive”. Here, we studied the behavior ...
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Female meiotic drive in plants: mechanisms and dynamics

F. Finseth,  Current Opinion in Genetics and Development,  82:102101. 2023.
Female meiosis is fundamentally asymmetric, creating an arena for genetic elements to compete for inclusion in the egg to maximize their transmission. Centromeres, as mediators of chromosomal segregation, are prime candidates to evolve via ‘female meiotic drive’. According to ...
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A natural gene drive system confers reproductive isolation in rice

C. Wang, J. Wang, J. Lu, Y. Xiong, Z. Zhao, X. Yu, X. Zheng, J. Li, Q. Lin, Y. Ren, Y. Hu, X. He, C. Li, Y. Zeng, R. Miao, M. Guo, B. Zhang, Y. Zhu, Y. Zhang, W. Tang, Y. Wang, B. Hao, Q. Wang, S. Cheng, X. He, B. Yao, J. Gao, X. Zhu, H. Yu, Y. Wang, Y. S,  Cell,  2023.
Hybrid sterility restricts the utilization of superior heterosis of indica-japonica inter-subspecific hybrids. In this study, we report the identification of RHS12, a major locus controlling male gamete sterility in indica-japonica hybrid rice. We show that RHS12 consists of two ...
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Teosinte Pollen Drive guides maize domestication and evolution by RNAi

B. Berube , E. Ernst, J. Cahn, B. Roche, C. d. S. Alves, A. Scheben, A. Siepel, J. Ross-Ibarra, J. Kermicle and R. Martienssen,  bioRxiv,  2023.07.12.548689. 2023.
Meiotic drivers subvert Mendelian expectations by manipulating reproductive development to bias their own transmission. Chromosomal drive typically functions in asymmetric female meiosis, while gene drive is normally postmeiotic and typically found in males. Using single molecule ...
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Both male and female meiosis contribute to non-Mendelian inheritance of parental chromosomes in interspecific plant hybrids (Lolium x Festuca)

J. Majka, M. Glombik, A. Dolezalova, J. Knerova, M. T. M. Ferreira, Z. Zwierzykowski, M. Duchoslav, B. Studer, J. Dolezel, J. Bartos and D. Kopecky,  NEW PHYTOLOGIST,  2023.
Some interspecific plant hybrids show unequal transmission of chromosomes from parental genomes to the successive generations. It has been suggested that this is due to a differential behavior of parental chromosomes during meiosis. However, underlying mechanism is unknown. We ...
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Gene editing and agrifood systems

FAO,  FAO,  2022.
Gene-editing technologies represent a promising new tool for plant and animal breeding in low- and middle-income countries. They enhance precision and efficiency over current breeding methods and could lead to rapid development of improved plant varieties and animal breeds. ...
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Improvement of Resistance in Plants Against Insect-Pests Using Genome Editing Tools

S. Bhat and S. Kumar,  Genome Editing: Current Technology Advances and Applications for Crop Improvement,  2022.
During growth period plants are subjected to both biotic and abiotic stresses. Like other biotic stresses, insect-pests are the most serious challenge for the plants particularly in yield losses. Genome editing techniques are becoming an emerging technology bringing real ...
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Reflection on the Challenges, Accomplishments, and New Frontiers of Gene Drives

M. Melesse Vergara, J. Labbé and J. Tannous,  BioDesign Research,  2022:9853416. 2022.
Ongoing pest and disease outbreaks pose a serious threat to human, crop, and animal lives, emphasizing the need for constantgenetic discoveries that could serve as mitigation strategies. Gene drives are genetic engineering approaches discovered decadesago that may allow quick, ...
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Rye B chromosomes differently influence the expression of A chromosome-encoded genes depending on the host species

A. Boudichevskaia, A. Fiebig, K. Kumke, A. Himmelbach and A. Houben,  Chromosome Research,  2022.
The B chromosome (B) is a dispensable component of the genome in many species. To evaluate the impact of Bs on the transcriptome of the standard A chromosomes (A), comparative RNA-seq analyses of rye and wheat anthers with and without additional rye Bs were conducted. In both ...
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DriverSEAT: A spatially-explicit stochastic modelling framework for the evaluation of gene drives in novel target species

M. Legros and L. G. Barrett,  bioRxiv,  2022.06.13.496025. 2022.
Gene drives represent a potentially ground breaking technology for the control of undesirable species or the introduction of desirable traits in wild population, and there is strong interest in applying these technologies to a wide range of species across many domains including ...
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Supergene potential of a selfish centromere

F. Finseth, K. Brown, A. Demaree and L. Fishman,  Philos Trans R Soc Lond B Biol Sci,  377:20210208. 2022.
Selfishly evolving centromeres bias their transmission by exploiting the asymmetry of female meiosis and preferentially segregating to the egg. Such female meiotic drive systems have the potential to be supergenes, with multiple linked loci contributing to drive costs or ...
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Retraction Note: Selective inheritance of target genes from only one parent of sexually reproduced F1 progeny in Arabidopsis

T. Zhang, M. Mudgett, R. Rambabu, B. Abramson, X. Dai, T. P. Michael and Y. Zhao,  Nature Communications,  13:3270. 2022.
Retraction to: Nature Communications https://doi-org.proxy-um.researchport.umd.edu/10.1038/s41467-021-24195-5, published online 22 June 2021.We retract the article cited above because genotyping results from recent experiments are not consistent with the conclusions presented in ...
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Recent advancements in CRISPR/Cas technology for accelerated crop improvement

D. Das, D. L. Singha, R. R. Paswan, N. Chowdhury, M. Sharma, P. S. Reddy and C. Chikkaputtaiah,  Planta,  255:109. 2022.
The likelihood of reduced agricultural production due to highly turbulent climatic conditions increases as the global population expands. The second paradigm of stress-resilient crops with enhanced tolerance and increased productivity against various stresses is paramount to ...
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Biotechnological Road Map for Innovative Weed Management

A. C. S. Wong, K. Massel, Y. Lam, J. Hintzsche and B. S. Chauhan,  Frontiers in Plant Science,  13. 2022.
In most agriculture farmlands, weed management is predominantly reliant on integrated weed management (IWM) strategies, such as herbicide application. However, the overuse and misuse of herbicides, coupled with the lack of novel active ingredients, has resulted in the uptrend of ...
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The non-Mendelian behavior of plant B chromosomes

J. Chen, J. A. Birchler and A. Houben,  Chromosome Res,  2022.
B chromosomes, also known as supernumerary chromosomes, are dispensable elements in the genome of many plants, animals, and fungi. Many B chromosomes have evolved one or more drive mechanisms to transmit themselves at a higher frequency than predicted by Mendelian genetics, and ...
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B-A Chromosome Translocations Possessing an A Centromere Partly Overcome the Root-Restricted Process of Chromosome Elimination in Aegilops speltoides

D. Li, A. Ruban, J. Fuchs, H. Kang and A. Houben,  Frontiers in Cell and Developmental Biology,  10. 2022.
Some eukaryotes exhibit dramatic genome size differences between cells of different organs, resulting from the programmed elimination of chromosomes. Aegilops speltoides is an annual diploid species from the Poaceae family, with a maximum number of eight B chromosomes (Bs) in ...
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Studying the active role of the maize B chromosome in the modulation of gene expression

University of Missouri,  Phys Org,  2022.
A team of University of Missouri biologists has made a new discovery that provides novel insights into the function and properties of the maize B chromosome. The study was led by Dr. Xiaowen Shi and Dr. Hua Yang, postdoctoral fellows in the Birchler lab, and reported in the ...
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Effect of aneuploidy of a nonessential chromosome on gene expression in maize

X. Shi, H. Yang, C. Chen, J. Hou, T. Ji, J. Cheng and J. A. Birchler,  Plant Journal,  2022.
The nonessential supernumerary maize B chromosome (B) has recently been shown to contain active genes and be capable of impacting gene expression of the A chromosomes. However, the effect of the B chromosome on gene expression is still unclear. In addition, it is unknown whether ...
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Versatile Applications of the CRISPR/Cas Toolkit in Plant Pathology and Disease Management

M. S. Wheatley and Y. N. Yang,  Phytopathology,  111:1080-1090. 2021.
New tools and advanced technologies have played key roles in facilitating basic research in plant pathology and practical approaches for disease management and crop health. Recently. the CRISPR/Cas (clustered regularly interspersed short palindromic repeats/CRISPR-associated) ...
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Analysis of the Segregation Distortion of FcRAN1 Genotypes Based on Whole-Genome Resequencing of Fig (Ficus carica L.) Breeding Parents

H. Ikegami, K. Shirasawa, H. Yakushiji, S. Yabe, M. Sato, T. Hayashi, K. Tashiro and H. Nogata,  Frontiers in Plant Science,  12:8. 2021.
The common fig (Ficus carica L.) has a gynodioecious breeding system, and its sex phenotype is an important trait for breeding because only female plant fruits are edible. During breeding to select for female plants, we analyzed the FcRAN1 genotype, which is strongly associated ...
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UC San Diego scientists develop the first CRISPR/Cas9-based gene drive in plants

M. Aguilera,  UC San Diego News Center,  2021.
With a goal of breeding resilient crops that are better able to withstand drought and disease, University of California San Diego scientists have developed the first CRISPR-Cas9-based gene drive in plants. While gene drive technology has been developed in insects to help stop the ...
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Selective inheritance of target genes from only one parent of sexually reproduced F1 progeny in Arabidopsis

T. Zhang, M. Mudgett, R. Rambabu, B. Abramson, X. Dai, T. P. Michael and Y. Zhao,  Nature Communications,  12:3854. 2021.
Sexual reproduction constrains progeny to inherit allelic genes from both parents. Selective acquisition of target genes from only one parent in the F1 generation of plants has many potential applications including the elimination of undesired alleles and acceleration of trait ...
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Ethics of Genome Editing

European Group on Ethics,  European Group on Ethics in Science and New Technologies,  2021.
This Opinion addresses the profound ethical questions raised and revived by them. It analyses various domains of application, from human health to animal experimentation, from livestock breeding to crop variety and to gene drives. With its wide view across areas, it identifies ...
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Holocentric Chromosomes Probably Do Not Prevent Centromere Drive in Cyperaceae

M. Kratka, J. Smerda, K. Lojdova, P. Bures and F. Zedek,  Frontiers in Plant Science,  12:9. 2021.
In response to these selfish centromeres, the histone protein CenH3, which recruits kinetochore components, adaptively evolves to restore chromosomal parity and counter the detrimental effects of centromere drive. Holocentric chromosomes, whose kinetochores are assembled along ...
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Atypical meiosis can be adaptive in outcrossed Schizosaccharomyces pombe due to wtf meiotic drivers

M. A. Bravo Núñez, I. M. Sabbarini, L. E. Eide, R. L. Unckless and S. E. Zanders,  eLife,  9:e57936. 2020.
Here, we demonstrate that in scenarios analogous to outcrossing, wtf drivers generate a fitness landscape in which atypical spores, such as aneuploids and diploids, are advantageous. In this context, wtf drivers can decrease the fitness costs of mutations that disrupt meiotic ...
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Case Study 2: Oilseed Rape (Brassica napus L.)

Johnannes L. Frieß, Broder Breckling, Kathrin Pascher and Windfried Schröder,  Gene Drives at Tipping Points,  2020.
SPAGESelf-Propagating Artificial Genetic Elements (SPAGE) (Self-Propagating Artificial Genetic Element) technologies allow for a proliferation of genetic information on the populationPopulation level at a higher rate than usual Mendelian inheritanceMendelian inheritance. ...
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Gene technologies in weed management: a technical feasibility analysis

N. Kumaran, A. Choudhary, M. Legros, A. W. Sheppard, L. G. Barrett, D. M. Gardiner and S. Raghu,  Current Opinion in Insect Science,  38:6-14. 2020.
With the advent of new genetic technologies such as gene silencing and gene drive, efforts to develop additional management tools for weed management is gaining significant momentum. These technologies promise novel ways to develop sustainable weed control options because gene ...
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Herbicide resistant weeds: A call to integrate conventional agricultural practices, molecular biology knowledge and new technologies

V. E. Perotti, A. S. Larran, V. E. Palmieri, A. K. Martinatto and H. R. Permingeat,  Plant Science,  290:110255. 2019.
Herbicide resistant (HR) weeds are of major concern in modern agriculture. This situation is exacerbated by the massive adoption of herbicide-based technologies along with the overuse of a few active ingredients to control weeds over vast areas year after year. Also, many other ...
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Herbicide resistant weeds: A call to integrate conventional agricultural practices, molecular biology knowledge and new technologies

V. E. Perotti, A. S. Larran, V. E. Palmieri, A. K. Martinatto and H. R. Perrningeat,  Plant Science,  290:15. 2019.
Herbicide resistant (HR) weeds are of major concern in modern agriculture. This situation is exacerbated by the massive adoption of herbicide-based technologies along with the overuse of a few active ingredients to control weeds over vast areas year after year. Also, many other ...
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B chromosome first—mechanisms behind the drive of B chromosomes uncovered

Leibniz Institute of Plant Genetics and Crop Plant Research,  Phy Org,  2019.
The specific number of chromosomes is one of the defining characteristics of a species. Whilst the common fruit fly carries 8 chromosomes, the genome of bread wheat counts 42 chromosomes. In comparison, the human genome is made out of a total of 46 chromosomes. However, about 15% ...
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A natural, conditional gene drive in plants

Conner, AJJ, J.M.E.,  bioRxiv,  519884:1-10. 2019.
A new class of gene drive in plant populations with herbicide resistance is described; a conditional gene drive that operates following herbicide application. Screening progeny from controlled crosses of Brassica napus heterozygous for a dominant allele conferring chlorsulfuron ...
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Transmission ratio distortion is frequent in Arabidopsis thaliana controlled crosses

Seymour, DKC, E.; Arioz, B. I.; Koenig, D.; Weigel, D.,  Heredity,  122:294-304. 2019.
The equal probability of transmission of alleles from either parent during sexual reproduction is a central tenet of genetics and evolutionary biology. Yet, there are many cases where this rule is violated. The preferential transmission of alleles or genotypes is termed ...
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Making a murderer: The evolutionary framing of hybrid gamete-killers

Sweigart, ALB, Yaniv; Fishman, Lila,  Trends in Genetics,  35:245-252. 2019.
Recent molecular investigations of hybrid incompatibilities have revealed fascinating patterns of genetic interactions that have been interpreted as the remnants of a history of selfish evolution. Instead of framing hybrid incompatibilities in light of genetic conflict, we ...
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Gene drives in plants: opportunities and challenges for weed control and engineered resilience

Barrett, LGL, Mathieu; Kumaran, Nagalingam; Glassop, Donna; Raghu, S.; Gardiner, Donald M.,  Proceedings of the Royal Society B: Biological Sciences,  286:9. 2019.
Plant species, populations and communities are under threat from climate change, invasive pathogens, weeds and habitat fragmentation. Despite considerable research effort invested in genome engineering for crop improvement, the development of genetic tools for the management of ...
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Gene driving the farm: who decides, who owns, and who benefits?

Montenegro de Wit, M,  Agroecology and Sustainable Food Systems,  43:1054-1074. 2019.
This commentary essay explores the social and ecological implications of gene-driving agriculture.
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Forcing the Farm

etc group,  etc group,  2018.
This report is being issued as an alert to governments, civil society organisations and grassroots movements. It points to how gene drives, while promoted as a tool for medicine and conservation, will find their real use in food and farming by agribusiness. It calls for a pause ...
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Gene drive systems: Do they have a place in agricultural weed management?

Neve, P,  Pest Management Science,  74:2672-2679. 2018.
There is a pressing need for novel control techniques in agricultural weed management. Direct genetic control of agricultural pests encompasses a range of techniques to introduce and spread novel, fitness-reducing genetic modifications through pest populations. Recently, the ...
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Identifying and detecting potentially adverse ecological outcomes associated with the release of gene-drive modified organisms

Hayes, KRH, G. R.; Dana, G. V.; Foster, S. D.; Ford, J. H.; Thresher, R.; Ickowicz, A.; Peel, D.; Tizard, M.; De Barro, P.; Strive, T.; Dambacher, J. M.,  Journal of Responsible Innovation,  5:S139-S158. 2018.
Synthetic gene drives could provide new solutions to a range of old problems such as controlling vector-borne diseases, agricultural pests and invasive species. In this paper, we outline methods to identify hazards and detect potentially adverse ecological outcomes at the ...
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THE NATIONAL BIOSAFETY TECHNICAL COMMISSION (CTNBio) NORMATIVE RESOLUTION No. 16, OF JANUARY 15, 2018

CTNBio,  National Biosafety Technical Commission of Brasil,  2018.
Sets forth the technical requirements for submitting an inquiry to the CTNBio concerning Precision Breeding Innovation Techniques. THE NATIONAL BIOSAFETY TECHNICAL COMMISSION (CTNBio), using its legal and regulatory powers and in observance of sections XV and XVI of article 14 of ...
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Gene drive inhibition by the anti-CRISPR proteins AcrIIA2 and AcrIIA4 in Saccharomyces cerevisiae

Basgall, EMG, S. C.; Goeckel, M. E.; Giersch, R. M.; Roggenkamp, E.; Schrock, M. N.; Halloran, M.; Finnigan, G. C.,  Microbiology-Sgm,  164:464-474. 2018.
Given the widespread use and application of the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas gene editing system across many fields, a major focus has been the development, engineering and discovery of molecular means to precisely control and regulate ...
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A CRISPR–Cas9-based gene drive platform for genetic interaction analysis in Candida albicans

Shapiro, RSC, Alejandro; Porter, Caroline B. M.; Hamblin, Meagan; Kaas, Christian S.; DiCarlo, James E.; Zeng, Guisheng; Xu, Xiaoli; Revtovich, Alexey V.; Kirienko, Natalia V.; Wang, Yue; Church, George M.; Collins, James J.,  Nature Microbiology,  3:73-82. 2018.
Candida albicans is the leading cause of fungal infections; yet, complex genetic interaction analysis remains cumbersome in this diploid pathogen. Here, we developed a CRISPR–Cas9-based ‘gene drive array’ platform to facilitate efficient genetic analysis in C. albicans. In ...
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CRISPR-based gene drives for pest control

McFarlane, GRW, C. Bruce A.; Lillico, Simon G.,  Trends in Biotechnology,  36:130-133. 2018.
Clustered regularly interspaced short palindromic repeats (CRISPR)-based gene drives (GDs) could be used to spread desirable genetic elements through wild populations. With the imminent development of this technology in vertebrates, we believe that it is timely to highlight two ...
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Veni, vidi, vici: the success of wtf meiotic drivers in fission yeast

López Hernández, JFZ, Sarah E.,  Yeast,  35:447-453. 2018.
Meiotic drivers are selfish DNA loci that can bias their own transmission into gametes. Owing to their transmission advantages, meiotic drivers can spread in populations even if the drivers or linked variants decrease organismal fitness. Meiotic drive was first formally described ...
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Development of a multi-locus CRISPR gene drive system in budding yeast

Yan, YF, Gregory C.,  Scientific reports,  8:17277-17277. 2018.
The discovery of CRISPR/Cas gene editing has allowed for major advances in many biomedical disciplines and basic research. One arrangement of this biotechnology, a nuclease-based gene drive, can rapidly deliver a genetic element through a given population and studies in fungi and ...
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Tuning CRISPR-Cas9 gene grives in Saccharomyces cerevisiae

Roggenkamp, EG, Rachael M.; Schrock, Madison N.; Turnquist, Emily; Halloran, Megan; Finnigan, Gregory C.,  G3-Genes Genomes Genetics,  8:999. 2018.
Control of biological populations is an ongoing challenge in many fields, including agriculture, biodiversity, ecological preservation, pest control, and the spread of disease. In some cases, such as insects that harbor human pathogens (e.g., malaria), elimination or reduction of ...
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Illinois study advances possibility of genetic control for major agricultural weeds

L. Quinn,  ACES News,  2017.
Waterhemp and Palmer amaranth, two aggressive weeds that threaten the food supply in North America, are increasingly hard to kill with commercially available herbicides. A novel approach known as genetic control could one day reduce the need for these chemicals. Now, scientists ...
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Is it time for synthetic biodiversity conservation?

Piaggio, AJS, G.; Seddon, P. J.; Alphey, L.; Bennett, E. L.; Carlson, R. H.; Friedman, R. M.; Kanavy, D.; Phelan, R.; Redford, K. H.; Rosales, M.; Slobodian, L.; Wheeler, K.,  Trends in Ecology & Evolution,  32:97-107. 2017.
Evidence indicates that, despite some critical successes, current conservation approaches are not slowing the overall rate of biodiversity loss. The field of synthetic biology, which is capable of altering natural genomes with extremely precise editing, might offer the potential ...
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wtf genes are prolific dual poison-antidote meiotic drivers

Nuckolls, NLN, M. A. B.; Eickbush, M. T.; Young, J. M.; Lange, J. J.; Yu, J. S.; Smith, G. R.; Jaspersen, S. L.; Malik, H. S.; Zanders, S. E.,  eLife,  6:e26033. 2017.
Meiotic drivers are selfish genes that bias their transmission into gametes, defying Mendelian inheritance. Despite the significant impact of these genomic parasites on evolution and infertility, few meiotic drive loci have been identified or mechanistically characterized. Here, ...
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B chromosome in Plantago lagopus Linnaeus, 1753 shows preferential transmission and accumulation through unusual processes

Dhar, MKK, G.; Kaul, S.,  Comparative Cytogenetics,  11:375-391. 2017.
Plantago lagopus is a diploid (2n = 2x = 12) weed belonging to family Plantaginaceae. We reported a novel B chromosome in this species composed of 5S and 45S ribosomal DNA and other repetitive elements. In the present work, presence of B chromosome(s) was confirmed through FISH ...
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Engineering species-like barriers to sexual reproduction

Maselko, MH, Stephen C.; Chacón, Jeremy M.; Harcombe, William R.; Smanski, Michael J.,  Nature Communications,  8:883. 2017.
Controlling the exchange of genetic information between sexually reproducing populations has applications in agriculture, eradication of disease vectors, control of invasive species, and the safe study of emerging biotechnology applications. Here we introduce an approach to ...
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A large gene family in fission yeast encodes spore killers that subvert Mendel’s law

Hu, WJ, Z. D.; Suo, F.; Zheng, J. X.; He, W. Z.; Du, L. L.,  eLife,  6:e28567. 2017.
Spore killers in fungi are selfish genetic elements that distort Mendelian segregation in their favor. It remains unclear how many species harbor them and how diverse their mechanisms are. Here, we discover two spore killers from a natural isolate of the fission yeast ...
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B Chromosomes – A matter of chromosome drive

Houben, A,  Frontiers in Plant Science,  8:210. 2017.
B chromosomes are supernumerary chromosomes which are often preferentially inherited, deviating from usual Mendelian segregation. The balance between the so-called chromosome drive and the negative effects that the presence of Bs applies on the fitness of their host determines ...
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The End of the GMO? Genome Editing, Gene Drives and New Frontiers of Plant Technology

K. L. Hefferon and R. J. Herring,  Review of Agrarian Studies,  7. 2017.
mprovements to agriculture will constitute one of the world’s greatest challenges in the coming century. Political and social controversies, as well as complications of plant breeding, intellectual property, and regulation, have compromised the promised impact of genetically ...
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Marcus Rhoades on preferential segregation in maize

Birchler, JA,  Genetics,  203:1489-1490. 2016.
Rhoades was studying a variant form of chromosome 10 with a conspicuous abnormality; it carried extensive heterochromatin at the tip of the long arm. This variant had been found by Albert Longley in indigenous maize varieties from the southwestern United States and provided to ...
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A meiotic drive element in the maize pathogen Fusarium verticillioides is located within a 102 kb region of chromosome V

Pyle, JP, T.; Merrill, B.; Nsokoshi, C.; McCall, M.; Proctor, R. H.; Brown, D. W.; Hammond, T. M.,  G3-Genes Genomes Genetics,  6:2543-2552. 2016.
Fusarium verticillioides is an agriculturally important fungus because of its association with maize and its propensity to contaminate grain with toxic compounds. Some isolates of the fungus harbor a meiotic drive element known as Spore killer (Sk(K)) that causes nearly all ...
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Comparative analysis of regions with distorted segregation in three diploid populations of potato

Manrique-Carpintero, NCC, J. J.; Veilleux, R. E.; Buell, C. R.; Douches, D. S.,  G3-Genes Genomes Genetics,  6:2617-2628. 2016.
Genes associated with gametic and zygotic selection could underlie segregation distortion, observed as alterations of expected Mendelian genotypic frequencies in mapping populations. We studied highly dense genetic maps based on single nucleotide polymorphisms to elucidate the ...
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Pollen killer gene S35 function requires interaction with an activator that maps close to S24, another pollen killer gene in rice

Kubo, TY, A.; Kurata, N.,  G3-Genes Genomes Genetics,  6:1459-1468. 2016.
Pollen killer genes disable noncarrier pollens, and are responsible for male sterility and segregation distortion in hybrid populations of distantly related plant species. The genetic networks and the molecular mechanisms underlying the pollen killer system remain largely ...
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The dawn of active genetics

Gantz, VMB, E.,  Bioessays,  38:50-63. 2016.
On December 18, 2014, a yellow female fly quietly emerged from her pupal case. What made her unique was that she had only one parent carrying a mutant allele of this classic recessive locus. Then, one generation later, after mating with a wild-type male, all her offspring ...
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Mating type and spore killing characterization of Fusarium verticillioides strains

Guo, LB, A. Z.; Geiser, D. M.; Jimenez-Gasco, M. D.; Kuldau, G. A.,  Mycological Progress,  14:1045. 2015.
Fusarium verticillioides is a heterothallic ascomycete causing maize ear rot, and produces fumonisin mycotoxins harmful to livestock and human health. A meiotic drive phenomenon called spore killing has been reported in several filamentous fungi including F. verticillioides. F. ...
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Centromere-associated meiotic drive and female fitness variation in Mimulus

Fishman, LK, J. K.,  Evolution,  69:1208-1218. 2015.
Female meiotic drive, in which chromosomal variants preferentially segregate to the egg pole during asymmetric female meiosis, is a theoretically pervasive but still mysterious form of selfish evolution. Like other selfish genetic elements, driving chromosomes may be maintained ...
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Duplication and adaptive evolution of a key centromeric protein in Mimulus, a genus with female meiotic drive

Finseth, FRD, Y. Z.; Saunders, A.; Fishman, L.,  Molecular Biology and Evolution,  32:2694-2706. 2015.
The fundamental asymmetry of female meiosis creates an arena for genetic elements to compete for inclusion in the egg, promoting the selfish evolution of centromere variants that maximize their transmission to the future egg. Such "female meiotic drive" has been hypothesized to ...
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Safeguarding CRISPR-Cas9 gene drives in yeast

DiCarlo, JEC, A.; Dietz, S. L.; Esvelt, K. M.; Church, G. M.,  Nature Biotechnology,  33:1250-1255. 2015.
RNA-guided gene drives capable of spreading genomic alterations made in laboratory organisms through wild populations could be used to address environmental and public health problems. However, the possibility of unintended genome editing occurring through the escape of strains ...
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A critical component of meiotic drive in Neurospora is located near a chromosome rearrangement

Harvey, AMR, D. G.; Groskreutz, K. M.; Kuntz, D. R.; Sharp, K. J.; Shiu, P. K. T.; Hammond, T. M.,  Genetics,  197:1165-1179. 2014.
Neurospora fungi harbor a group of meiotic drive elements known as Spore killers (Sk). Spore killer-2 (Sk-2) and Spore killer-3 (Sk-3) are two Sk elements that map to a region of suppressed recombination. Although this recombination block is limited to crosses between Sk and ...
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Genes that bias Mendelian segregation

Grognet, PL, H.; Malagnac, F.; Silar, P.,  PLOS Genetics,  10:e1004387. 2014.
Mendel laws of inheritance can be cheated by Meiotic Drive Elements (MDs), complex nuclear genetic loci found in various eukaryotic genomes and distorting segregation in their favor. Here, we identify and characterize in the model fungus Podospora anserina Spok1 and Spok2, two ...
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Analysis of segregation distortion and its relationship to hybrid barriers in rice

Reflinur, K, B.; Jang, S. M.; Chu, S. H.; Bordiya, Y.; Akter, M. B.; Lee, J.; Chin, J. H.; Koh, H. J.,  Rice,  7:3. 2014.
Segregation distortion (SD) is a frequently observed occurrence in mapping populations generated from crosses involving divergent genotypes. In the present study, ten genetic linkage maps constructed from reciprocal F-2 and BC1F1 mapping populations derived from the parents ...
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Evolution and biology of supernumerary B chromosomes

Houben, AB-M, A. M.; Klemme, S.; Timmis, J. N.,  Cellular and Molecular Life Sciences,  71:467-478. 2014.
B chromosomes (Bs) are dispensable components of the genome exhibiting non-Mendelian inheritance and have been widely reported on over several thousand eukaryotes, but still remain an evolutionary mystery ever since their first discovery over a century ago [1]. Recent advances in ...
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Diversity and abundance of the abnormal chromosome 10 meiotic drive complex in Zea mays

Kanizay, LBP, T.; Lowry, E. G.; Hufford, M. B.; Peterson, D. G.; Ross-Ibarra, J.; Dawe, R. K.,  Heredity,  110:570-577. 2013.
Maize Abnormal chromosome 10 (Ab10) contains a classic meiotic drive system that exploits the asymmetry of meiosis to preferentially transmit itself and other chromosomes containing specialized heterochromatic regions called knobs. The structure and diversity of the Ab10 meiotic ...
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Complex genetic nature of sex-independent transmission ratio distortion in Asian rice species: the involvement of unlinked modifiers and sex-specific mechanisms

Koide, YS, Y.; Ikenaga, M.; Sawamura, N.; Matsubara, K.; Onishi, K.; Kanazawa, A.; Sano, Y.,  Heredity,  108:242-247. 2012.
Transmission ratio distortion (TRD), in which one allele is transmitted more frequently than the opposite allele, is presumed to act as a driving force in the emergence of a reproductive barrier. TRD acting in a sex-specific manner has been frequently observed in interspecific ...
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B chromosomes in plants

Jones, N,  Plant Biosystems,  146:727-737. 2012.
B chromosomes (Bs) can be described as "selfish chromosomes", a term that has been used for the repetitive DNA which comprises the bulk of the genome in large genome species, except that Bs have a life of their own as independent chromosomes. They can accumulate in number by ...
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Molecular dissection of Neurospora Spore killer meiotic drive elements

Hammond, TMR, D. G.; Xiao, H.; Shiu, P. K. T.,  Proceedings of the National Academy of Sciences of the United States of America,  109:12093-12098. 2012.
Meiotic drive is a non-Mendelian inheritance phenomenon in which certain selfish genetic elements skew sexual transmission in their own favor. In some cases, progeny or gametes carrying a meiotic drive element can survive preferentially because it causes the death or ...
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Nondisjunction in favor of a Chromosome: The mechanism of rye B chromosome drive during pollen mitosis

Banaei-Moghaddam, AMS, V.; Kumke, K.; Weiss, O.; Klemme, S.; Nagaki, K.; Macas, J.; Gonzalez-Sanchez, M.; Heredia, V.; Gomez-Revilla, D.; Gonzalez-Garcia, M.; Vega, J. M.; Puertas, M. J.; Houben, A.,  Plant Cell,  24:4124-4134. 2012.
B chromosomes (Bs) are supernumerary components of the genome and do not confer any advantages on the organisms that harbor them. The maintenance of Bs in natural populations is possible by their transmission at higher than Mendelian frequencies. Although drive is the key for ...
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Selective microspore abortion correlated with aneuploidy: an indication of meiotic drive

Furness, CAR, P. J.,  Sexual Plant Reproduction,  24:1-8. 2011.
Selective megaspore abortion (monomegaspory) probably arose once in seed plants and occurs routinely in more than 70% of angiosperm species, representing one of the key characters of a heterosporous life history. In contrast, selective microspore abortion leading to pollen ...
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Transmission ratio distortion in Arabidopsis lyrata: effects of population divergence and the S-locus

Leppala, JB, J. S.; Schierup, M. H.; Savolainen, O.,  Heredity,  100:71-78. 2008.
We investigated transmission ratio distortion within an Icelandic population of Arabidopsis lyrata using 16 molecular markers unlinked to the S-locus. Transmission ratio distortion was found more often than expected by chance at the gametic level, but not at the genotypic or ...
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The evolution of sex-independent transmission ratio distortion involving multiple allelic interactions at a single locus in rice

Koide, YI, M.; Sawamura, N.; Nishimoto, D.; Matsubara, K.; Onishi, K.; Kanazawa, A.; Sano, Y.,  Genetics,  180:409-420. 2008.
Transmission ratio distortion (TRD) is frequently observed in inter-and intraspecific hybrids of plants, leading to a violation of Mendelian inheritance. Sex-independent TRD (siTRD) was detected in a hybrid between Asian cultivated rice and its wild ancestor. Here we examined how ...
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Broadening the application of evolutionarily based genetic pest management

Gould, F,  Evolution,  62:500-510. 2008.
Insect- and tick-vectored diseases such as malaria, dengue fever, and Lyme disease cause human suffering, and current approaches for prevention are not adequate. Invasive plants and animals such as Scotch broom, zebra mussels, and gypsy moths continue to cause environmental ...
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Centromere-associated female meiotic drive entails male fitness costs in Monkeyflowers

Fishman, LS, A.,  Science,  322:1559-1562. 2008.
Female meiotic drive, in which paired chromosomes compete for access to the egg, is a potentially powerful but rarely documented evolutionary force. In interspecific monkeyflower ( Mimulus) hybrids, a driving M. guttatus allele ( D) exhibits a 98: 2 transmission advantage via ...
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Neurospora spore killers Sk-2 and Sk-3 suppress meiotic silencing by unpaired DNA

Raju, NBM, R. L.; Shiu, P. T.,  Genetics,  176:43-52. 2007.
In Neurosphora, crassa., pairing of homologous DNA segments is monitored during meiotic prophase I. Any genes not paired with a homolog, as well as any paired homologs of that gene, are silenced during the sexual phase by a mechanism known as meiotic silencing by unpaired DNA ...
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Identification and characterization of segregation distortion loci along chromosome 5B in tetraploid wheat

Kumar, SG, B. S.; Faris, J. D.,  Molecular Genetics and Genomics,  278:187-196. 2007.
Segregation distortion genes are widespread in plants and animals and function by their effect on competition among gametes for preferential fertilization. In this study, we evaluated the segregation distortion of molecular markers in multiple reciprocal backcross populations ...
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Segregation distortion in Arabidopsis C24/Col-0 and Col-0/C24 recombinant inbred line populations is due to reduced fertility caused by epistatic interaction of two loci

Torjek, OW-W, H.; Meyer, R. C.; von Korff, M.; Kusterer, B.; Rautengarten, C.; Altmann, T.,  Theoretical and Applied Genetics,  113:1551-1561. 2006.
A new large set of reciprocal recombinant inbred lines (RILs) was created between the Arabidopsis accessions Col-0 and C24 for quantitative trait mapping approaches, consisting of 209 Col-0 x C24 and 214 C24 x Col-0 F-7 RI lines. Genotyping was performed using 110 evenly ...
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The maize Ab 10 meiotic drive system maps to supernumerary sequences in a large complex haplotype

Mroczek, RJM, J. R.; Luce, A. C.; Hiatt, E. N.; Dawe, R. K.,  Genetics,  174:145-154. 2006.
The meiotic drive system on maize abnormal chromosome 10 (Ab10) is contained within a terminal domain of chromatin that extends the long arm of Ab10 to similar to 1.3 times the size of normal chromosome 10L. Ab10 type I (Ab10-I) does not recombine with normal chromosome 10 (N10) ...
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Degeneration and domestication of a selfish gene in yeast: Molecular evolution versus site-directed mutagenesis

Koufopanou, VB, A.,  Molecular Biology and Evolution,  22:1535-1538. 2005.
VDE is a homing endonuclease gene in yeasts with an unusual evolutionary history including horizontal transmission, degeneration, and domestication into the mating-type switching locus HO. We investigate here the effects of these features on its molecular evolution. In addition, ...
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A novel meiotic drive locus almost completely distorts segregation in Mimulus (monkeyflower) hybrids

Fishman, LW, J. H.,  Genetics,  169:347-353. 2005.
We report the discovery, mapping, and characterization of a meiotic drive locus (D) exhibiting nearly 100% nonrandom transmission in hybrids between two species of yellow monkeyflowers, outcrossing Mimulus guttatus and selfing M. nasutus. Only 1% of F-2 hybrids were M. nasutus ...
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B chromosomes and genome size in flowering plants

Trivers, RB, A.; Palestis, B. G.,  Genome,  47:1-8. 2004.
B chromosomes are extra chromosomes found in some, but not all, individuals within a species, often maintained by giving themselves an advantage in transmission, i.e. they drive. Here we show that the presence of B chromosomes correlates to and varies strongly and positively with ...
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Homing endonuclease genes: the rise and fall and rise again of a selfish element

Burt, AK, V.,  Current Opinion in Genetics & Development,  14:609-615. 2004.
Homing endonuclease genes (HEGs) are selfish genetic elements that spread by first cleaving chromosomes that do not contain them and then getting copied across to the broken chromosome as a byproduct of the repair process. The success of this strategy will depend on the ...
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Analysis of two additional loci in Neurospora crassa related to Spore killer-2

Turner, BC,  Fungal Genetics and Biology,  39:142-150. 2003.
Two new loci found in one strain of Neurospora crassa (P2604) collected in Malaya are related to the meiotic drive system Spore killer Sk-2. Sk-2 was found in Neurospora intermedia and introgressed into N. crassa. P2604 showed high resistance to killing when crossed to Sk-2. This ...
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Common features of segregation distortion in plants and animals

Taylor, DRI, P. K.,  Genetica,  117:27-35. 2003.
Segregation distortion is increasingly recognized as a potentially powerful evolutionary force. This runs counter to the perception that non-Mendelian genes are rare genetic curiosities, a view that seems to be supported by the near ubiquity of the Mendelian system of ...
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B chromosomes in plants: escapees from the A chromosome genome?

Jones, NH, A.,  Trends in Plant Science,  8:417-423. 2003.
B chromosomes are dispensable elements that do not recombine with the A chromosomes of the regular complement and that follow their own evolutionary track. In some cases, they are known to be nuclear parasites with autonomous modes of inheritance, exploiting 'drive' to ensure ...
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Four loci on abnormal chromosome 10 contribute to meiotic drive in maize

Hiatt, END, R. K.,  Genetics,  164:699-709. 2003.
We provide a genetic analysis of the meiotic drive system on maize abnormal chromosome 10 (Ab10) that causes preferential segregation of specific chromosomal regions to the reproductive megaspore. The data indicate that at least four chromosomal regions contribute to meiotic ...
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The meiotic drive system on maize abnormal chromosome 10 contains few essential genes

Hiatt, END, R. K.,  Genetica,  117:67-76. 2003.
In maize, a distal portion of abnormal chromosome 10 (Ab10) causes the meiotic drive of itself as well as many unlinked heterochromatic regions known as knobs. The Ab10 drive system, which encodes trans- as well as cis-acting components, occupies a large region of chromosome 10L ...
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Sexual transmission of the Het-s prion leads to meiotic drive in Poldospora anserina

Dalstra, HJPS, K.; Debets, A. J. M.; Saupe, S. J.; Hoekstra, R. F.,  Proceedings of the National Academy of Sciences of the United States of America,  100:6616-6621. 2003.
In the filamentous fungus Podospora anserina, two phenomena are associated with polymorphism at the het-s locus, vegetative incompatibility and ascospore abortion. Two het-s alleles occur naturally, het-s and het-S. The het-s encoded protein is a prion propagating as a ...
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Marcus Rhoades, preferential segregation and meiotic drive

Birchler, JAD, R. K.; Doebley, J. F.,  Genetics,  164:835-841. 2003.
LONG before microarray biologists coined and promoted the term “discovery science,” maize geneticists were avid practitioners of this mode of investigation. In fact, one might say that for a number of years, the field of maize genetics basically operated as discovery science. ...
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Adaptation for horizontal transfer in a homing endonuclease

Koufopanou, VG, M. R.; Burt, A.,  Molecular Biology and Evolution,  19:239-246. 2002.
Selfish genes of no function other than self-propagation are susceptible to degeneration if they become fixed in a population. and regular transfer to new species may be the only means for their long-term persistence. To test this idea we surveyed 24 species of yeast for VDE, a ...
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Transmission ratio distortion due to the bl gene in table beet

Austin, DG, I. L.,  Journal of the American Society for Horticultural Science,  126:340-343. 2001.
The bl gene conditions a blotchy phenotype (irregular sectors of red and white root color) in table beet (Beta vulgaris ssp, vulgaris). Segregation of the bl gene was found to be consistent with a single recessive gene, however, some evidence for a departure from a single gene ...
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Spore-killing meiotic drive factors in a natural population of the fungus Podospora anserina

van der Gaag, MD, A. J. M.; Oosterhof, J.; Slakhorst, M.; Thijssen, Jagm; Hoekstra, R. F.,  Genetics,  156:593-605. 2000.
In fungi, meiotic drive is observed as spore killing. In the secondarily homothallic ascomycete Podospora anserina it is characterized by the abortion of two of the four spores in the ascus. We have identified seven different types of meiotic drive elements (Spore killers). Among ...
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Recurrent invasion and extinction of a selfish gene

Goddard, MRB, A.,  Proceedings of the National Academy of Sciences of the United States of America,  96:13880-13885. 1999.
Homing endonuclease genes show super-Mendelian inheritance, which allows them to spread in populations even when they are of no benefit to the host organism. To test the idea that regular horizontal transmission is necessary for the long-term persistence of these genes, we ...
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Meiotic drive of chromosomal knobs reshaped the maize genome

Buckler, ESP-D, T. L.; Buckler, C. S. K.; Dawe, R. K.; Doebley, J. F.; Holtsford, T. P.,  Genetics,  153:415-426. 1999.
Meiotic drive is the subversion of meiosis so that particular genes are preferentially transmitted to the progeny. Meiotic drive generally causes the preferential segregation of small regions of the genome; however, in maize we propose that meiotic drive is responsible for the ...
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Identification of the t complex-encoded cytoplasmic dynein light chain Tctex1 in inner arm I1 supports the involvement of flagellar dyneins in meiotic drive

Harrison, AO-C, P.; King, S. M.,  Journal of Cell Biology,  140:1137-1147. 1998.
The cytoplasmic dynein light chain Tctex1 is a candidate for one of the distorter products involved in the non-Mendelian transmission of mouse t haplotypes. It has been unclear, however, how the t-specific mutations in this protein, which is found associated with cytoplasmic ...
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Localization of the genes controlling B chromosome transmission rate in maize (Zea mays ssp. mays, Poaceae)

Chiavarino, AMR, M.; Rosi, P.; Poggio, L.; Naranjo, C. A.,  American Journal of Botany,  85:1581-1585. 1998.
In previous papers we found that the frequency of B chromosomes in native races of maize varies considerably in different populations. Moreover, we found genotypes that control high and low transmission rates (TR) of B chromosomes in the Pisingallo race. In the present work ...
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Selfish DNA and breeding system in flowering plants

Burt, AT, R.,  Proceedings of the Royal Society B-Biological Sciences,  265:141-146. 1998.
In many species, some individuals carry one or more B chromosomes: extra, or supernumerary chromosomes not part of the normal complement. In most well-studied cases, B's lower the fitness of their carrier and persist in populations only because of accumulation mechanisms ...
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Genetic control of B chromosome transmission rate in Zea mays ssp mays (Poaceae)

Rosato, MC, A. M.; Naranjo, C. A.; Puertas, M. J.; Poggio, L.,  American Journal of Botany,  83:1107-1112. 1996.
We selected genotypes of high and low B chromosome transmission rate (TR) in a native race of maize (Pisingallo) from northwest Argentina. We made 20 female 0B x male 1B and 20 f.1B x m.0B crosses. The former (G0m) showed a large variation of B TR, with a mean of TR +/- SE = 0.52 ...
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Meiotic drive in fungi: Chromosomal elements that cause fratricide and distort genetic ratios

Raju, NB,  Journal of Genetics,  75:287-296. 1996.
Fungal Spore killers (Sk), studied most extensively in Neurospora and to a lesser extent in Podospora, Gibberella and Cochliobolus, cause the death of ascospores (= meiospores) that do not contain the killer (Sk(K)) element. When a Spore killer is heterozygous (Sk(K) x Sk(S)) in ...
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The inheritance of B chromosomes in Allium schoenoprasum L

Bougourd, SMP, A. B.,  Chromosome Research,  4:151-158. 1996.
The inheritance of B chromosomes has been investigated in Allium schoenoprasum from the River Wye, Powys; controlled crosses between plants of known B chromosome constitution were carried out, and the numbers of Bs present in the progenies scored. There was considerable ...
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Ascoycete spore killers: Chromosomal elements that distort genetic ratios among the products of meiosis

Raju, NB,  Mycologia,  86:461-473. 1994.
Spore killers (Sk), studied most extensively in Neurospora, are also known in Podospora, Gibberella and Cochliobolus. Spore killers are no doubt present in natural populations of other fungi. Criteria are outlined here for recognizing their presence and distinguishing them from ...
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Bewildering Bs – An impression of the 1st B-chromosome conference

Beukeboom, LW,  Heredity,  73:328-336. 1994.
Ever since their first discovery B chromosomes have attracted attention. Why are they so appealing? The standard chromosomes of an organism are A chromosomes; B chromosomes are extra to this normal complement. In the B chromosome 'bible' (Jones & Rees, 1982) Bs are defined as ...
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Didymium iridis reproductive systems: Additions and meiotic drive

Clark, JL, J. C.,  Mycologia,  85:764-768. 1993.
Three heterothallic Mexican isolates (Mex 1, Mex 2, and Mex 3) of Didymium iridis belong to the reproductively isolated A5 mating series of this morphospecies. This was unexpected in that the sole previous A5 isolate was from Georgia and the Mexican isolates were collected in ...
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Evolutionary dynamics of spore killers

Nauta, MJH, R. F.,  Genetics,  135:923-930. 1993.
Spore killing in ascomycetes is a special form of segregation distortion. When a strain with the Killer genotype is crossed to a Sensitive type, spore killing is expressed by asci with only half the number of ascospores as usual, all surviving ascospores being of the Killer type. ...
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Meiotic drive in Neurospora and other fungi

Turner, BCP, D. D.,  American Naturalist,  137:416-429. 1991.
When a gene complex called Spore killer is heterozygous, ascospores representing two of the four products of each meiosis are killed. Only those that receive the killer complex survive. This article reviews what is known of the mode of action of the Neurospora Spore killers, ...
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Expression of meiotic drive elements Spore Killer-2 and Spore Killer-3 in asci of Neurospora tetrasperma

Raju, NBP, D. D.,  Genetics,  129:25-37. 1991.
It was shown previously that when a chromosomal Spore killer factor is heterozygous in Neurospora species with eight-spored asci, the four sensitive ascospores in each ascus die and the four survivors are all killers. Sk-2K and Sk-3K are nonrecombining haplotypes that segregate ...
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Inheritance in Nicotiana tabacum XXVII. Pollen Killer, An alien genetic locus inducing abortion of microspores not carrying it

D. R. Cameron and R. M. Moav,  Genetics,  42:326. 1957.
A cytogenetic study of experimental introgression from N. plumbaginifolia (pbg) into N. tabacum (tbc) has been pursued in this laboratory for several years (CLAUSEN 1952). In the hybrid derivatives it was observed that genically controlled pollen abortion was associated with the ...
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Preferential segregation in maize

M. M. Rhoades,  Genetics,  27:395-407. 1942.
An abnormal type of chromosome 10, found by Longley in maize from the s.-w. part of the U. S., is preferentially segregated during megasporogenesis. More than 70% of the ovules receive the abnormal chromosome instead of the 50% expected with random segregation. At pachytene the ...
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