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Sensing Actin Dynamics through Adherens Junctions.

ABSTRACT: We study punctate adherens junctions (pAJs) to determine how short-lived cadherin clusters and relatively stable actin bundles interact despite differences in dynamics. We show that pAJ-linked bundles consist of two distinct regions-the bundle stalk (AJ-BS) and a tip (AJ-BT) positioned between cadherin clusters and the stalk. The tip differs from the stalk in a number of ways: it is devoid of the actin-bundling protein calponin, and exhibits a much faster F-actin turnover rate. While F-actin in the stalk displays centripetal movement, the F-actin in the tip is immobile. The F-actin turnover in both the tip and stalk is dependent on cadherin cluster stability, which in turn is regulated by F-actin. The close bidirectional coupling between the stability of cadherin and associated F-actin shows how pAJs, and perhaps other AJs, allow cells to sense and coordinate the dynamics of the actin cytoskeleton in neighboring cells-a mechanism we term "dynasensing."

SUBMITTER: Indra I

PROVIDER: S-EPMC7093076 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Sensing Actin Dynamics through Adherens Junctions.

Indra Indrajyoti I Troyanovsky Regina B RB Shapiro Lawrence L Honig Barry B Troyanovsky Sergey M SM

Cell reports 20200201 8

We study punctate adherens junctions (pAJs) to determine how short-lived cadherin clusters and relatively stable actin bundles interact despite differences in dynamics. We show that pAJ-linked bundles consist of two distinct regions-the bundle stalk (AJ-BS) and a tip (AJ-BT) positioned between cadherin clusters and the stalk. The tip differs from the stalk in a number of ways: it is devoid of the actin-bundling protein calponin, and exhibits a much faster F-actin turnover rate. While F-actin in ...[more]

PMID: 32101754

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Dataset Information

Sensing Actin Dynamics through Adherens Junctions.

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Sensing Actin Dynamics through Adherens Junctions.

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