A PtdIns(3,4,5)P₃ dispersal switch engages cell ratcheting at specific cell surfaces.

ABSTRACT: Force generation in epithelial tissues is often pulsatile, with actomyosin networks generating contractile forces before cyclically disassembling. This pulsed nature of cytoskeletal forces implies that there must be ratcheting mechanisms that drive processive transformations in cell shape. Previous work has shown that force generation is coordinated with endocytic remodeling; however, how ratcheting becomes engaged at specific cell surfaces remains unclear. Here, we report that PtdIns(3,4,5)P₃ is a critical lipid-based cue for ratcheting engagement. The Sbf RabGEF binds to PIP₃, and disruption of PIP₃ reveals a dramatic switching behavior in which medial ratcheting is activated and epithelial cells begin globally constricting apical surfaces. PIP₃

SUBMITTER: Miao H 

PROVIDER: S-EPMC8483019 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature