Formation of a beta(1) integrin signaling complex in Schwann cells is independent of Rho

    Authors

    A. R. Taylor; S. E. Geden;C. Fernandez-Valle

    Abbreviated Journal Title

    Glia

    Keywords

    myelination; differentiation; focal adhesion; FOCAL ADHESION KINASE; MYELIN FORMATION; BASAL LAMINA; PERIPHERAL-NERVE; LD4 MOTIF; PAXILLIN; PROTEIN; CYTOSKELETAL; EXPRESSION; BETA-1-INTEGRIN; Neurosciences

    Abstract

    Schwann cell adhesion to basal lamina is essential for peripheral nerve development. beta(1) integrin receptors for extracellular matrix cooperate with other receptors to transmit signals that coordinate cell cycle progression and initiation of differentiation, including myelin-specific gene expression. In Schwann cell/sensory neuron co-cultures, beta(1) integrins complex with focal adhesion kinase (FAK), fyn kinase, paxillin, and schwannomin in response to basal lamina adhesion. To study the assembly of this signaling complex in Schwann cells (SCs), we induced 0, integrin clustering on suspended cells using an immobilized antibody and recovered a complex containing beta(1) integrin, FAK, paxillin, and schwannomin. In adherent subconfluent cells, the proteins colocalized to filopodia, ruffling membranes and focal contacts. We assessed the role of rhoGTPase in the process of integrin complex assembly by introducing C3 transferase (C3T), a rho inhibitor, into the cells. Although C3T caused dose-dependent morphological abnormalities, FAK, paxillin, and schwannomin were able to coimmunoprecipitate with beta(1) integrin. Additionally, colocalization of FAK, paxillin, and schwannomin with beta(1) integrin in filopodia and small focal contacts remained unchanged. We conclude that SCs do not require active rho to recruit signaling and structural proteins to beta(1) integrins clustered at the plasma membrane. Rho is required to establish large focal adhesions and to spread and stabilize plasma membrane extensions. (C) 2003 Wiley-Liss, Inc.

    Journal Title

    Glia

    Volume

    41

    Issue/Number

    1

    Publication Date

    1-1-2003

    Document Type

    Article

    Language

    English

    First Page

    94

    Last Page

    104

    WOS Identifier

    WOS:000180158400010

    ISSN

    0894-1491

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