[대학원 생명과학과 세미나 안내]
연사 : 허성호 교수 (University of Nebraska Medical Center)
연제 : Crosstalk Between Mesenchyme And Epithelium For Cochlear Sensory Progenitor Generation
일시 : 2016년 6월 13일 (월) 오후 4시
장소 : 하나과학관 A동 207호
초청교수 : 최의주 교수
Abstract
Cochlear sensory progenitor cell population, which generates hair cells and supporting cells in the organ of Corti, has been formed during development and remains unchanged once formed. Due to lack of regenerative capability of cochlear sensory epithelium in human and mouse, once damaged, cochlear hair cells are lost permanently resulting hearing loss. Therefore, understanding how sensory progenitor cell population is formed is critical to cochlear sensory cell regeneration. Fgf9 and Fgf20 are expressed in nonsensory and sensory epithelium during cochlear progenitor cell formation, respectively. Loss of Fgf9 and Fgf20 resulted in shortened cochlear length in addition to loss of outer hair cells and supporting cells and disrupted pattern formation. Staining of Sox2 shows decreased cochlear progenitor populations in Fgf9 and Fgf20 compound mutants. This decrease is due to decrease of sensory progenitors proliferation. Tissue specific deletion of Fgfr1 and Fgfr2 shows that Fgfr1 in sensory epithelium is required only in lateral compartment differentiation and pattern formation, and mesenchymal Fgfr1 and Fgfr2 are required only for proper cochlear length through cochlear progenitor cell proliferation. In addition, ectopic activation of Fgf signal in mesenchymal cells is enough to increase of cochlear progenitor cell proliferation and of cochlear length. These data elucidate roles of Fgf9/20-Fgfr1/2 signal axis required for cochlear progenitor formation, and may be used for cochlear sensory cell regeneration.