Membrane Supply and Demand Regulates F-Actin in a Cell Surface Reservoir

作者：Figard Lauren; Wang Mengyu; Zheng Liuliu; Golding Ido; Sokac Anna Marie^*

来源：Developmental Cell, 2016, 37(3): 267-278.

DOI：10.1016/j.devcel.2016.04.010

Cells store membrane in surface reservoirs of pits and protrusions. These membrane reservoirs facilitate cell shape change and buffer mechanical stress, but we do not know how reservoir dynamics are regulated. During cellularization, the first cytokinesis in Drosophila embryos, a reservoir of microvilli unfolds to fuel cleavage furrow ingression. We find that regulated exocytosis adds membrane to the reservoir before and during unfolding. Dynamic F-actin deforms exocytosed membrane into microvilli. Single microvilli extend and retract in similar to 20 s, while the overall reservoir is depleted in sync with furrow ingression over 60-70 min. Using pharmacological and genetic perturbations, we show that exocytosis promotes microvillar F-actin assembly, while furrow ingression controls microvillar F-actin disassembly. Thus, reservoir F-actin and, consequently, reservoir dynamics are regulated by membrane supply from exocytosis and membrane demand from furrow ingression.

• 出版日期2016-5-9