报告题目：A novel sex determination gene in fire ants
报告人：John Wang博士
报告时间：2015年12月18日下午15:00
报告地点：禧强楼报告厅
主办单位：海峡联合研究院基因组中心
报告人简介：
John Wang 1995年在美国Ohio State University获得学士学位，2002年在美国Stanford University获得博士学位，2003年-2010年在瑞士University of Lausanne从事博士后研究。2010年起任台湾中央研究院生物多样性研究中心助研究员。主要研究兴趣集中在社会昆虫的行为学、进化、遗传学和基因组学。其相关研究工作以第一作者或通讯作者身份发表在Science、Nature、PNAS、PLoS Genetics、Genome Biology和BiaEssays等国际知名期刊。
报告摘要：
Sex determination is a fundamental biological process that is regulated by a bewildering large number of molecular mechanisms. In about 20% of insects, including all ants and bees, sex is determined by the ploidy of the individual. Males are haploid and develop from unfertilized eggs with one set of chromosomes. Females are diploid and obtain two sets of chromosomes from fertilization. In several species, the mechanism to ascertain ploidy has been proposed to be complementary sex determination (csd): heterozygous individuals at the sex locus develop into females, whereas hemizygous haploid or homozygous diploid individuals develop into males. Studies in the honeybee Apis mellifera have identified a single locus, csd, as the master sex determination gene. We are using the fire ant Solenopsis invicta to study the mechanisms of sex determination in ants. Our genetic analyses have revealed that fire ants have evolved a novel master sex determination gene. We have mapped the sex locus to a 131 kb region containing at least ten genes, all without similarity to known sex genes. By comparing genomes of different individuals we also identified a hypervariable region with at least 10 alleles, consistent with balancing selection acting on the sex determination locus to maintain its heterozygosity. We are currently conducting gene expression analyses and functional tests to identify and characterize this novel sex determination system.