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Mammalian formin-1 participates in adherens junctions and polymerization of linear actin cables.

ABSTRACT: During epithelial sheet formation, linear actin cables assemble at nascent adherens junctions. This process requires alpha-catenin and actin polymerization, although the underlying mechanism is poorly understood. Here, we show that formin-1 interacts with alpha-catenin, localizes to adherens junctions and nucleates unbranched actin filaments. Furthermore, disruption of the alpha-catenin-formin-1 interaction blocks assembly of radial actin cables and perturbs intercellular adhesion. A fusion protein of the beta-catenin-binding domain of alpha-catenin with the actin polymerization domains of formin-1 rescues formation of adherens junctions and associated actin cables in alpha-catenin-null keratinocytes. These findings provide new insight into how alpha-catenin orchestrates actin dynamics during intercellular junction formation.

SUBMITTER: Kobielak A

PROVIDER: S-EPMC2605950 | biostudies-literature | 2004 Jan

REPOSITORIES: biostudies-literature

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Mammalian formin-1 participates in adherens junctions and polymerization of linear actin cables.

Kobielak Agnieszka A Pasolli H Amalia HA Fuchs Elaine E

Nature cell biology 20031130 1

During epithelial sheet formation, linear actin cables assemble at nascent adherens junctions. This process requires alpha-catenin and actin polymerization, although the underlying mechanism is poorly understood. Here, we show that formin-1 interacts with alpha-catenin, localizes to adherens junctions and nucleates unbranched actin filaments. Furthermore, disruption of the alpha-catenin-formin-1 interaction blocks assembly of radial actin cables and perturbs intercellular adhesion. A fusion prot ...[more]

PMID: 14647292

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