ESCRT Machinery Is Required for Plasma Membrane Repair

TLDR

Plasma membrane damage arises from many causes, and efficient repair—via endocytosis, membrane patching, or extracellular budding—is essential for cell survival. Real‑time imaging and correlative scanning electron microscopy revealed extracellular budding and shedding at sites of ESCRT recruitment. ESCRT proteins are rapidly recruited to plasma membrane wounds and are essential for repairing small lesions, as quantitative kinetics and modeling show, with ESCRT‑mediated extracellular shedding ensuring wound closure.

Abstract

Plasma membrane damage can be triggered by numerous phenomena, and efficient repair is essential for cell survival. Endocytosis, membrane patching, or extracellular budding can be used for plasma membrane repair. We found that endosomal sorting complex required for transport (ESCRT), involved previously in membrane budding and fission, plays a critical role in plasma membrane repair. ESCRT proteins were recruited within seconds to plasma membrane wounds. Quantitative analysis of wound closure kinetics coupled to mathematical modeling suggested that ESCRTs are involved in the repair of small wounds. Real-time imaging and correlative scanning electron microscopy (SEM) identified extracellular buds and shedding at the site of ESCRT recruitment. Thus, the repair of certain wounds is ensured by ESCRT-mediated extracellular shedding of wounded portions.