Photoreceptor Discs: Built Like Ectosomes

Overview

Journal Trends Cell Biol

Specialty Cell Biology

Date 2020 Sep 9

PMID 32900570

Citations 42

Authors

William J Spencer

Tylor R Lewis

Jillian N Pearring

Vadim Y Arshavsky

Affiliations

Soon will be listed here.

Abstract

The light-sensitive outer segment organelle of the vertebrate photoreceptor cell is a modified cilium filled with hundreds of flattened 'disc' membranes that provide vast light-absorbing surfaces. The outer segment is constantly renewed with new discs added at its base every day. This continuous process is essential for photoreceptor viability. In this review, we describe recent breakthroughs in the understanding of disc morphogenesis, with a focus on the molecular mechanisms responsible for initiating disc formation from the ciliary membrane. We highlight the discoveries that this mechanism evolved from an innate ciliary process of releasing small extracellular vesicles, or ectosomes, and that both disc formation and ectosome release rely on the actin cytoskeleton.

Citing Articles

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