Guy1-conferred female lethality: mechanism and application for mosquito control

 描述(申请人提供)：按蚊是疟疾的主要媒介，疟疾是人类最致命和代价最高的疾病之一。随着抗药性和杀虫剂的传播，疟疾控制措施正受到越来越大的威胁。最近开发的基因组资源和遗传方法为增进我们对蚊子生物学的了解和制定防治疟疾和其他蚊媒疾病的新战略提供了前所未有的机会。尽管Y染色体在雄性决定和雄性生物学的其他方面具有重要作用，但在按蚊中仍未被发现。由于吸血和疾病病原体的传播是雌性蚊子的唯一领域，因此在采用遗传方法减少蚊子数量或用难以传播疾病的种群取代合格的媒介种群时，关键是只释放雄性蚊子。克服了技术瓶颈，我们最近在An中发现了四个Y基因。斯特芬西。在这些因素中，Guy1是男性决定M因素的最佳候选者。获得了多个表达Guy1基因的转基因株系，多代共产生6520个转基因雄株和0个转基因雌株。我们的初步数据还表明，观察到的GUY1转基因AN的雌性致死率为100%。Stephensi可能是由于剂量补偿调节不当所致。重要的是，已知的三个性别决定主开关--性别-致死、Fem/Masc、xo-致死1，也分别直接或间接调节果蝇、家蚕和秀丽线虫的剂量补偿。功能性致死等位基因的丧失和Masc靶标的敲除分别导致黑腹黑腹鼠和家蚕的雌性胚胎致死。在这里，我们将检验这一假设。Stephensi Guy1是性别决定或剂量补偿或两者兼而有之的主要调节者。我们将追求以下具体目标：1)确定Guy1是否控制剂量补偿和/或性别决定；2)描述Guy1功能的分子机制；3)利用Guy1转基因作为一种手段在按蚊中进行性别分离和种群减少。

 DESCRIPTION (provided by applicant): Anopheles mosquitoes are the primary vectors of malaria, one of humankind's most deadly and costly diseases. Malaria control measures are under increasing threat as drug- and insecticide- resistance spreads. Recently developed genomic resources and genetic methods provide unprecedented opportunities to improve our understanding of mosquito biology and develop new strategies to combat malaria and other mosquito-borne diseases. Y chromosome remains unexplored in Anopheles mosquitoes despite its importance in male determination and other aspects of male biology. Since blood feeding and, consequently, the transmission of disease pathogens is the sole province to female mosquitoes, it is critical to release only males when implementing genetic approaches for reducing mosquito populations or for replacing competent vector populations with populations that are refractory to disease transmission. Overcoming technical bottlenecks, we have recently uncovered four Y genes in An. stephensi. Among these, Guy1 is the best candidate for the male-determining M factor. Multiple Guy1-expressing transgenic lines were generated, which produced 6520 transgenic males and 0 transgenic females over multiple generations. Our preliminary data also suggest that the observed 100% female lethality in the Guy1 transgenic An. stephensi may result from mis-regulation of dosage compensation. Importantly, three known master switches of sex-determination, sex-lethal, Fem/Masc, xo-lethal 1, also directly or indirectly regulate dosage compensation in Drosophila melanogaster, Bombyx mori, and Caenorhabditis elegans, respectively. Loss of function sex- lethal alleles and knockdown of the target of Masc cause female embryonic lethality in D. melanogaster and B. mori, respectively. Here, we will test the hypothesis that the An. stephensi Guy1 is a master regulator of either sex-determination or dosage compensation or both. We will pursue the following specific aims: 1) To determine whether Guy1 controls dosage compensation and/or sex-determination; 2) To delineate the molecular mechanism underlying Guy1 function; and 3) To exploit Guy1 transgenics as a means for sex separation and population reduction in Anopheles mosquitoes.