Behavioral isolation (Zimbabwe vs. cosmopolitan Drosophila melanogaster)

Two behavioral races, M (for cosmopolitan) and Z (for Zimbabwe) of D. melanogaster provide a great model to study the genetic basis of racial differentiation. A series of genetic analyses showed that the Z/M behavioral isolation is mainly contributed by two major autosomes, and several fragments of the third chromosome are crucial in either male behavior or female preferences. We generated a reference genome of Z race by deep sequencing and identified candidate genes by population genomic approach.

Host adaptation (D. sechellia)

D. sechellia, an emerging model for the genetics of host specialization, is an island endemic species that has adapted to chemical toxins present in the fruit of its host plant, Morinda citrifolia. Its sibling species, D. simulans, and many other Drosophila species do not tolerate these toxins and avoid the fruit. Earlier work found a region with a strong effect on tolerance to the major toxin, octanoic acid, on chromosome arm 3R. Using a novel assay, we narrowed this region to a small span near the centromere containing 18 genes.

Parthenogenesis (Asexual reproduction in D. albomicans)

The parthenogenetic strains of Drosophila species provide great models to dissect the genetics of parthenogenesis and how parthenogenesis evolves from sexual reproduction. To map the candidate loci responsible for parthenogenesis, 366 F₂ recombinant females were phenotyped. Among them, 192 F₂ recombinant females have been genotyped by multiplexed shotgun (MSG) sequencing (a type of genotyping by sequencing). We expect to map the genetic loci by QTL approach.

Meiotic drive (D. simulans)

Meiotic drive has profound evolutionary consequences, as many general principles of population genetics theory are violated by non-Mendelian segregation. For example, it has the potential to form new species through the accumulation of genetic incompatibility. We have identified two elements on the X chromosome responsible for the sex ratio meiotic drive in D. simulans. A selection of significant candidate genes, provided by genetic mapping and expression studies, will be subjected to functional validation using appropriate transgenic tools developed in D. simulans.

近年研究主題

• 異種雜交雄性子代不孕的分子遺傳學

• 性別隔離的行為分析

• 同種精子競爭優勢的遺傳基

• 擬黃果蠅的族群基因學