成体干细胞的发现和研究通过为治疗各种医疗状况提供了新的机会,彻底改变了再生医学。羊膜干细胞,在其一生中保留其全部增殖能力和全部分化范围,与哺乳动物成体干细胞相比,具有更大的潜力,只表现出有限的干细胞潜能。因此,了解这些差异背后的机制具有重要意义。在这次审查中,我们研究了羊膜动物和哺乳动物中成年视网膜干细胞的异同,从它们在视神经囊泡中的胚胎阶段到它们在胚胎后视网膜干细胞小生境中的停留,位于视网膜周边的睫状边缘区。在羊膜动物中,视网膜干细胞的发育前体在其向视杯的复杂形态发生重塑中迁移过程中暴露于各种环境线索。相比之下,一旦它们就位,它们在视网膜周边的哺乳动物对应物主要由邻近组织指示。我们探索了哺乳动物和硬骨鱼视杯形态发生的不同模式,并强调了控制形态发生和干细胞指令的分子机制。该综述总结了睫状边缘区形成的分子机制,并提供了比较单细胞转录组学研究的影响的观点,以揭示进化的相似性和差异。
The discovery and
study of adult stem cells have revolutionized regenerative medicine by offering new opportunities for treating various medical conditions. Anamniote stem cells, which retain their full proliferative capacity and full differentiation range throughout their lifetime, harbour a greater potential compared to mammalian adult stem cells, which only exhibit limited stem cell potential. Therefore, understanding the mechanisms underlying these differences is of significant interest. In this review, we examine the similarities and differences of adult retinal stem cells in anamniotes and mammals, from their embryonic stages in the optic vesicle to their residence in the postembryonic retinal stem cell niche, the ciliary marginal zone located in the retinal periphery. In anamniotes, developing precursors of retinal stem cells are exposed to various environmental cues during their migration in the complex morphogenetic remodelling of the optic vesicle to the optic cup. In contrast, their mammalian counterparts in the retinal periphery are primarily instructed by neighbouring tissues once they are in place. We explore the distinct modes of optic cup morphogenesis in mammals and teleost fish and highlight molecular mechanisms governing morphogenesis and stem cells instruction. The review concludes with the molecular mechanisms of ciliary marginal zone formation and offers a perspective on the impact of comparative single cell transcriptomic studies to reveal the evolutionary similarities and differences.