Formins regulate the actin-related protein 2/3 complex-independent polarization of the centrosome to the immunological synapse.
Journal Article (Journal Article)
T cell receptor (TCR)-mediated cytoskeletal reorganization is considered to be actin-related protein (Arp) 2/3 complex dependent. We therefore examined the requirement for Arp2/3- and formin-dependent F-actin nucleation during T cell activation. We demonstrated that without Arp2/3-mediated actin nucleation, stimulated T cells could not form an F-actin-rich lamellipod, but instead produced polarized filopodia-like structures. Moreover, the microtubule-organizing center (MTOC, or centrosome), which rapidly reorients to the immunological synapse through an unknown mechanism, polarized in the absence of Arp2/3. Conversely, the actin-nucleating formins, Diaphanous-1 (DIA1) and Formin-like-1 (FMNL1), did not affect TCR-stimulated F-actin-rich structures, but instead displayed unique patterns of centrosome colocalization and controlled TCR-mediated centrosome polarization. Depletion of FMNL1 or DIA1 in cytotoxic lymphocytes abrogated cell-mediated killing. Altogether, our results have identified Arp2/3 complex-independent cytoskeletal reorganization events in T lymphocytes and indicate that formins are essential cytoskeletal regulators of centrosome polarity in T cells.
Full Text
Duke Authors
Cited Authors
- Gomez, TS; Kumar, K; Medeiros, RB; Shimizu, Y; Leibson, PJ; Billadeau, DD
Published Date
- February 2007
Published In
Volume / Issue
- 26 / 2
Start / End Page
- 177 - 190
PubMed ID
- 17306570
Pubmed Central ID
- PMC2836258
International Standard Serial Number (ISSN)
- 1074-7613
Digital Object Identifier (DOI)
- 10.1016/j.immuni.2007.01.008
Language
- eng
Conference Location
- United States