Science
[Report] A male-determining factor in the mosquito Aedes aegypti
Andrew Brantley Hall, Sanjay Basu, Xiaofang Jiang, Yumin Qi, Vladimir A. Timoshevskiy, James K. Biedler, Maria V. Sharakhova, Rubayet Elahi, Michelle A. E. Anderson, Xiao-Guang Chen, Igor V. Sharakhov, Zach N. Adelman, Zhijian Tu.
Sex determination in the mosquito Aedes aegypti is governed by a dominant male-determining factor (M factor) located within a Y chromosome–like region called the M locus. Here, we show that an M-locus gene, Nix, functions as an M factor in A. aegypti. Nix exhibits persistent M linkage and early embryonic expression, two characteristics required of an M factor. Nix knockout with clustered regularly interspaced short palindromic repeats (CRISPR)–Cas9 resulted in largely feminized genetic males and the production of female isoforms of two key regulators of sexual differentiation: doublesex and fruitless. Ectopic expression of Nix resulted in genetic females with nearly complete male genitalia. Thus, Nix is both required and sufficient to initiate male development. This study provides a foundation for mosquito control strategies that convert female mosquitoes into harmless males.