Actin-filament cross-linking protein T-plastin increases Arp2/3-mediated actin-based movement

Adeline Giganti, Julie Plastino, Bassam Janji, Marleen Van Troys, Delphine Lentz, Christophe Ampe, Cécile Sykes, Evelyne Friederich*

*Corresponding author for this work

    Research output: Contribution to journalArticleResearchpeer-review

    65 Citations (Scopus)

    Abstract

    Increasing evidence suggests that actin cross-linking or bundling proteins might not only structure the cortical actin cytoskeleton but also control actin dynamics. Here, we analyse the effects of T-plastin/T-fimbrin, a representative member of an important actin-filament cross-linking protein by combining a quantitative biomimetic motility assay with biochemical and cell-based approaches. Beads coated with the VCA domain of the Wiskott/Aldrich-syndrome protein (WASP) recruit the actin-nucleating Arp2/3 complex, polymerize actin at their surface and undergo movement when placed in cell-free extracts. T-Plastin increased the velocity of VCA beads 1.5 times, stabilized actin comets and concomitantly displaced cofilin, an actin-depolymerizing protein. T-Plastin also decreased the F-actin disassembly rate and inhibited cofilin-mediated depolymerization of actin filaments in vitro. Importantly, a bundling-incompetent variant comprising the first actin-binding domain (ABD1) had similar effects. In cells, this domain induced the formation of long actin cables to which other actin-regulating proteins were recruited. Altogether, these results favor a mechanism in which binding of ABD1 controls actin turnover independently of cross-link formation. In vivo, this activity might contribute to the assembly and maintenance of the actin cytoskeleton of plasma-membrane protrusions.

    Original languageEnglish
    Pages (from-to)1255-1265
    Number of pages11
    JournalJournal of Cell Science
    Volume118
    Issue number6
    DOIs
    Publication statusPublished - 15 Mar 2005

    Keywords

    • ADF
    • Bundling
    • CH domain
    • Cofilin
    • Nucleation
    • T-Fimbrin

    Fingerprint

    Dive into the research topics of 'Actin-filament cross-linking protein T-plastin increases Arp2/3-mediated actin-based movement'. Together they form a unique fingerprint.

    Cite this