[대학원 생명과학과 세미나 안내]
연사 : 이대한 교수(경희대학교 이과대학 생물학과)
연제 : Single-cell and single-gene dissection of nervous system evolution
일시 : 2022년 10월 07일 (금) 오후 4시 30분
장소 : 하나과학관 A동 109호
초청교수 : 이은진 교수
Abstract
Species-specific neurogenesis programs can generate various numbers and types of neurons to form unique nervous systems underlying distinct behaviors. To understand the divergence in animal nervous systems, we use as comparative models different Drosophila species, which display a rich repertoire of interspecific behavioral variation. Among thousands of species in the Drosophila genus, we analyzed three closely-related drosophilids, D. melanogaster (Dmel), D. simulans (Dsim) and D. sechellia (Dsec). These drosophilids exhibit distinct ecologies: Dmel and Dsim are cosmopolitan generalists, while the island endemic Dsec exhibits extreme niche specialism for ripe noni fruit, providing an evolutionary context for their differences. To investigate interspecific variability in nervous system cell types and gene expression, we applied single-nucleus RNA-sequencing (snRNA-seq) to the central brains and antennae of this trio of species. With this dataset, we are addressing following questions: Is there interspecific variation in the composition and organization among drosophilid nervous systems (e.g., species-specific gain, loss or modification of neuronal populations)? How does gene expression evolve in conserved cell types (e.g., conservation or diversification of cell-type specific gene expression profiles)? What are the molecular mechanisms of species-specific remodeling of the nervous system (e.g., how genetic variants modify GRNs or that control neurodevelopment or functional properties of mature neurons)? How do changes in cell types and gene expression impact the neural circuits and behaviors of the species? The discovery of evolving neuronal and non-neuronal populations in this drosophilid trio will provide an entry point to more broadly study the evolvability of nervous systems across and beyond the Drosophila genus.