Abstract:
The release of extracellular vesicles is observed across numerous cell types and serves a range of biological functions including intercellular communication and waste disposal. One cell type which stands out for its robust capacity to release extracellular vesicles is the vertebrate photoreceptor cell. For decades, the release of extracellular vesicles by photoreceptors has been documented in many different animal models of photoreceptor degeneration and, more recently, in wild type photoreceptors. Here, I review all studies describing extracellular vesicle release by photoreceptors and discuss the most unifying theme among them-a photoreceptor cell fully, or partially, diverts its light sensitive membrane material to extracellular vesicles when it has defects in the delivery or morphing of this material into the photoreceptor\'s highly organized light sensing organelle. Because photoreceptors generate an enormous amount of light sensitive membrane every day, the diversion of this material to extracellular vesicles can cause a massive accumulation of these membranes within the retina. Little is known about the uptake of photoreceptor derived extracellular vesicles, although in some cases the retinal pigment epithelial cells, microglia, Müller glia, and/or photoreceptor cells themselves have been shown to phagocytize them.
摘要:
在许多细胞类型中观察到细胞外囊泡的释放,并具有一系列生物学功能,包括细胞间通讯和废物处理。一种因其释放细胞外囊泡的强大能力而突出的细胞类型是脊椎动物感光细胞。几十年来,细胞外囊泡的释放由光感受器已经被记录在许多不同的动物模型的光感受器变性,最近,在野生型光感受器中。这里,我回顾了所有描述光感受器释放细胞外囊泡的研究,并讨论了其中最统一的主题-完全是感光细胞,或部分,当它的光敏感膜材料向光感受器的高度组织的光敏细胞器的递送或变形有缺陷时,它将其光敏膜材料转移到细胞外囊泡。因为光感受器每天都会产生大量的光敏膜,这种物质转移到细胞外囊泡可以导致这些膜在视网膜内大量积累。对感光细胞来源的细胞外囊泡的摄取知之甚少,虽然在某些情况下视网膜色素上皮细胞,小胶质细胞,Müllerglia,和/或感光细胞本身已被证明吞噬它们。