Regulation of the association of adducin with actin filaments by Rho-associated kinase (Rho-kinase) and myosin phosphatase.

Journal Article (Journal Article)

The small GTPase Rho is believed to regulate the actin cytoskeleton and cell adhesion through its specific targets. We previously identified the Rho targets: protein kinase N, Rho-associated kinase (Rho-kinase), and the myosin-binding subunit (MBS) of myosin phosphatase. Here we purified MBS-interacting proteins, identified them as adducin, and found that MBS specifically interacted with adducin in vitro and in vivo. Adducin is a membrane-skeletal protein that promotes the binding of spectrin to actin filaments and is concentrated at the cell-cell contact sites in epithelial cells. We also found that Rho-kinase phosphorylated alpha-adducin in vitro and in vivo and that the phosphorylation of alpha-adducin by Rho-kinase enhanced the interaction of alpha-adducin with actin filaments in vitro. Myosin phosphatase composed of the catalytic subunit and MBS showed phosphatase activity toward alpha-adducin, which was phosphorylated by Rho-kinase. This phosphatase activity was inhibited by the phosphorylation of MBS by Rho-kinase. These results suggest that Rho-kinase and myosin phosphatase regulate the phosphorylation state of adducin downstream of Rho and that the increased phosphorylation of adducin by Rho-kinase causes the interaction of adducin with actin filaments.

Full Text

Duke Authors

Cited Authors

  • Kimura, K; Fukata, Y; Matsuoka, Y; Bennett, V; Matsuura, Y; Okawa, K; Iwamatsu, A; Kaibuchi, K

Published Date

  • March 6, 1998

Published In

Volume / Issue

  • 273 / 10

Start / End Page

  • 5542 - 5548

PubMed ID

  • 9488679

International Standard Serial Number (ISSN)

  • 0021-9258

Digital Object Identifier (DOI)

  • 10.1074/jbc.273.10.5542

Language

  • eng

Conference Location

  • United States