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The adhesion modulation domain of Caenorhabditis elegans ?-catenin regulates actin binding during morphogenesis.

ABSTRACT: Maintaining tissue integrity during epidermal morphogenesis depends on ?-catenin, which connects the cadherin complex to F-actin. We show that the adhesion modulation domain (AMD) of Caenorhabditis elegans HMP-1/?-catenin regulates its F-actin-binding activity and organization of junctional-proximal actin in vivo. Deleting the AMD increases F-actin binding in vitro and leads to excess actin recruitment to adherens junctions in vivo. Reducing actin binding through a compensatory mutation in the C-terminus leads to improved function. Based on the effects of phosphomimetic and nonphosphorylatable mutations, phosphorylation of S509, within the AMD, may regulate F-actin binding. Taken together, these data establish a novel role for the AMD in regulating the actin-binding ability of an ?-catenin and its proper function during epithelial morphogenesis.

SUBMITTER: Shao X

PROVIDER: S-EPMC6743470 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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The adhesion modulation domain of Caenorhabditis elegans α-catenin regulates actin binding during morphogenesis.

Shao Xiangqiang X Lucas Bethany B Strauch Jared J Hardin Jeff J

Molecular biology of the cell 20190612 17

Maintaining tissue integrity during epidermal morphogenesis depends on α-catenin, which connects the cadherin complex to F-actin. We show that the adhesion modulation domain (AMD) of Caenorhabditis elegans HMP-1/α-catenin regulates its F-actin-binding activity and organization of junctional-proximal actin in vivo. Deleting the AMD increases F-actin binding in vitro and leads to excess actin recruitment to adherens junctions in vivo. Reducing actin binding through a compensatory mutation i ...[more]

PMID: 31188702

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