Abstract:
The light-detecting organelle of the photoreceptor cell is a modified primary cilium, called the outer segment. The outer segment houses hundreds of light-sensitive membrane, \"discs,\" that are continuously renewed by the constant formation of new discs at the outer segment base and the phagocytosis of old ones from outer segment tips by the retinal pigment epithelium. In this chapter, we describe how an actin cytoskeleton network, residing precisely at the site of disc formation, provides the driving force that pushes out the ciliary plasma membrane to form each disc evagination that subsequently can mature into a bona fide disc. We highlight the functions of actin-binding proteins, particularly PCARE and Arp2/3, that are known to participate in disc formation. Finally, we describe a working model of disc formation built upon the many studies focusing on the role of actin during disc morphogenesis.
摘要:
感光细胞的光检测细胞器是修饰的初级纤毛,称为外段。外部部分容纳了数百个光敏膜,\"光盘,通过在外段基部不断形成新的椎间盘和视网膜色素上皮从外段尖端吞噬旧椎间盘而不断更新。在这一章中,我们描述了肌动蛋白细胞骨架网络,恰好位于椎间盘形成的部位,提供了推动睫状质膜以形成每个椎间盘外泄的驱动力,该椎间盘外泄随后可以成熟成真正的椎间盘。我们强调了肌动蛋白结合蛋白的功能,特别是PCARE和Arp2/3,已知参与椎间盘形成。最后,我们描述了椎间盘形成的工作模型,建立在许多研究集中于肌动蛋白在椎间盘形态发生过程中的作用。