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CRMP-1 enhances EVL-mediated actin elongation to build lamellipodia and the actin cortex.

ABSTRACT: Cells can control actin polymerization by nucleating new filaments or elongating existing ones. We recently identified CRMP-1 as a factor that stimulates the formation of Listeria monocytogenes actin comet tails, thereby implicating it in actin assembly. We now show that CRMP-1 is a major contributor to actin assembly in epithelial cells, where it works with the Ena/VASP family member EVL to assemble the actin cytoskeleton in the apical cortex and in protruding lamellipodia. CRMP-1 and EVL bind to one another and together accelerate actin filament barbed-end elongation. CRMP-1 also stimulates actin assembly in the presence of VASP and Mena in vitro, but CRMP-1-dependent actin assembly in MDCK cells is EVL specific. Our results identify CRMP-1 as a novel regulator of actin filament elongation and reveal a surprisingly important role for CRMP-1, EVL, and actin polymerization in maintaining the structural integrity of epithelial sheets.

SUBMITTER: Yu-Kemp HC

PROVIDER: S-EPMC5551698 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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CRMP-1 enhances EVL-mediated actin elongation to build lamellipodia and the actin cortex.

Yu-Kemp Hui-Chia HC Kemp James P JP Brieher William M WM

The Journal of cell biology 20170619 8

Cells can control actin polymerization by nucleating new filaments or elongating existing ones. We recently identified CRMP-1 as a factor that stimulates the formation of <i>Listeria monocytogenes</i> actin comet tails, thereby implicating it in actin assembly. We now show that CRMP-1 is a major contributor to actin assembly in epithelial cells, where it works with the Ena/VASP family member EVL to assemble the actin cytoskeleton in the apical cortex and in protruding lamellipodia. CRMP-1 and EV ...[more]

PMID: 28630144

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