科研之友
微信
新浪微博
Facebook
分享链接
摘要
Sox2 is a well-established neuronal stem cell-associated transcription factor that regulates neural development and adult neurogenesis in vertebrates, and is one of the critical genes used to reprogram differentiated cells into induced pluripotent stem cells. We examined if Sox2 was involved in the early reprogramming-like events that Muller glia undergo as they upregulate many pluripotency- and neural stem cell-associated genes required for proliferation in light-damaged adult zebrafish retinas. In the undamaged adult zebrafish retina, Sox2 is expressed in Muller glia and a subset of amacrine cells, similar to other vertebrates. Following 31 h of light damage, Sox2 expression significantly increased in proliferating Muller glia. Morpholino-mediated knockdown of Sox2 expression resulted in decreased numbers of proliferating Muller glia, while induced overexpression of Sox2 stimulated Muller glia proliferation in the absence of retinal damage. Thus, Sox2 is necessary and sufficient for Muller glia proliferation. We investigated the role of Wnt/beta-catenin signaling, which is a known regulator of sox2 expression during vertebrate retinal development. While beta-catenin 2, but not beta-catenin 1, was necessary for Muller glia proliferation, neither beta-catenin paralog was required for sox2 expression following retinal damage. Sox2 expression was also necessary for ascl1a (neurogenic) and lin28a (reprogramming) expression, but not stat3 expression following retinal damage. Furthermore, Sox2 was required for Muller glial-derived neuronal progenitor cell amplification and expression of the pro-neural marker Tg(atoh7:EGFP). Finally, loss of Sox2 expression prevented complete regeneration of cone photoreceptors. This study is the first to identify a functional role for Sox2 during Muller glial-based regeneration of the vertebrate retina.
- 出版日期2017-8
