Keywords: sex determination

Partial masculinization of Aedes aegypti females by conditional expression of Nix

B. B. Kojin, E. Jakes, J. K. Biedler, Z. Tu and Z. N. Adelman,  PLOS Neglected Tropical Diseases,  16:e0010598. 2022.
Here, we report on the conditional expression of Nixin transgenic A. aegypti under the control of the tetracycline-dependent (Tet-off) system, with the goal of establishing repressible sex distortion. A masculinization phenotype was observed in three of the seven transgenic lines ...
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Manipulating Insect Sex Determination Pathways for Genetic Pest Management: Opportunities and Challenges

A. Siddall, T. Harvey-Samuel, T. Chapman and P. T. Leftwich,  Frontiers in Bioengineering and Biotechnology,  10. 2022.
Sex determination pathways in insects are generally characterised by an upstream primary signal, which is highly variable across species, and that regulates the splicing of a suite of downstream but highly-conserved genes (transformer, doublesex and fruitless). In turn, these ...
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The AalNix3&4 isoform is required and sufficient to convert Aedes albopictus females into males

Y. Zhao, B. Jin, P. Liu, X. Xiao, L. Cai, Z. Xie, L. Kong, T. Liu, W. Yang, Y. Wu, J. Gu, Z. Tu, A. A. James and X.-G. Chen,  PLOS Genetics,  18:e1010280. 2022.
Author summary Nix serves as a conserved male-determining factor in the two most important mosquito arboviral vectors, Ae. aegypti and Ae. albopictus. AaeNix alone can convert Ae. aegypti females into fertile but flightless males. AalNix has four alternative splice isoforms ...
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Selective targeting of biting females to control mosquito-borne infectious diseases

B. B. Kojin, A. Compton, Z. N. Adelman and Z. Tu,  Trends in Parasitology,  2022.
Mosquitoes are vectors for a number of infectious diseases. Only females feed on blood to provision for their embryos and, in doing so, transmit pathogens to the associated vertebrate hosts. Therefore, sex is an important phenotype in the context of genetic control programs, both ...
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A supernumerary “B-sex” chromosome drives male sex determination in the Pachón cavefish, Astyanax mexicanus

B. Imarazene, K. Du, S. Beille, E. Jouanno, R. Feron, Q. Pan, J. Torres-Paz, C. Lopez-Roques, A. Castinel, L. Gil, C. Kuchly, C. Donnadieu, H. Parrinello, L. Journot, C. Cabau, M. Zahm, C. Klopp, T. Pavlica, A. Al-Rikabi, T. Liehr, S. A. Simanovsky, J. Bo,  Current Biology,  2021.
Sex chromosomes are generally derived from a pair of classical type-A chromosomes, and relatively few alternative models have been proposed up to now.(1)(,)(2) B chromosomes (Bs) are supernumerary and dispensable chromosomes with non-Mendelian inheritance found in many plant and ...
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Transgenic expression of Nix converts genetic females into males and allows automated sex sorting in Aedes albopictus

C. Lutrat, R. P. Olmo, T. Baldet, J. Bouyer and E. Marois,  bioRxiv,  2021.07.28.454191. 2021.
Aedes albopictus is a major vector of arboviruses. Better understanding of its sex determination is crucial for developing mosquito control tools, especially genetic sexing strains. In Aedes aegypti, Nix is the primary gene responsible for masculinization and Nix-expressing ...
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femaleless Controls Sex Determination and Dosage Compensation Pathways in Females of Anopheles Mosquitoes

E. Krzywinska, L. Ferretti, J. Li, J.-C. Li, C.-H. Chen and J. Krzywinski,  Current Biology,  31:1084-1091.e4. 2021.
Here we show that in the African malaria mosquito Anopheles gambiae, a gene, which likely arose in the Anopheles lineage and which we call femaleless (fle), controls sex determination in females by regulating splicing of dsx and fruitless (fru; another terminal gene within a ...
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Sex Determination and Dosage Compensation: femaleless Is the Link in Anopheles Mosquitoes

M. Scott,  Current Biology,  31:R260-R263. 2021.
A new study finds that the femaleless gene is essential for sexual development and repression of X-chromosome dosage compensation in the malaria vector Anopheles gambiae. This could provide the basis for a new genetic approach to control this pest.
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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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Tackling Dengue fever by turning female mosquitoes into males

T. Sandle,  DIGTAL JOURNAL,  2020.
T. Sandle (2020). DIGTAL JOURNAL Genetic engineering appears to be the key for delivering mosquito control, according to new research. Scientists have successfully converted female mosquitoes into non-biting males.
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Researchers convert female mosquitoes to nonbiting males with implications for mosquito control

Virginia Tech,  ScienceDaily,  2020.
Researchers convert female mosquitoes to nonbiting males with implications for mosquito control Virginia Tech researchers have proven that a single gene can convert female Aedes aegypti mosquitoes into fertile male mosquitoes and identified a gene needed for male mosquito ...
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Identification and characterisation of a Masculinizer homolog in the diamondback moth Plutella xylostella

Harvey-Samuel, T., V. C. Norman, R. Carter, E. Lovett and L. Alphey,  Insect Molecular Biology,  2019:2019. 2019.
Recently, a novel sex-determination system was identified in the silkworm (Bombyx mori) in which a piRNA encoded on the female-specific W chromosome silences a Z-linked gene (Masculinizer) which would otherwise initiate male sex-determination and dosage compensation. ...
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Ecological and evolutionary applications for environmental sex reversal of fish

A. McNair, P. M. Lokman, G. P. Closs and S. Nakagawa,  Quarterly Review of Biology,  90:23-44. 2015.
Environmental sex reversal (ESR), which results in a mismatch between genotypic and phenotypic sex, is well documented in numerous fish species and may be induced by chemical exposure. Historically, research involving piscine ESR has been carried out with a view to improving ...
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Sperm traits of masculinized fish relative to wild-type males: a systematic review and meta-analyses

A. M. Senior, S. L. Johnson and S. Nakagawa,  Fish and Fisheries,  17:143-164. 2014.
Environmental sex reversal (ESR), whereby environmental effects (e.g. exogenous chemicals) override genetic sex determination, is a commonly used technique in aquaculture and physiology research. We performed a systematic review and meta-analyses of the literature that compares ...
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