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A cascade of protein kinase C isozymes promotes cytoskeletal polarization in T cells.

ABSTRACT: Polarization of the T cell microtubule-organizing center (MTOC) toward the antigen-presenting cell (APC) is driven by the accumulation of diacylglycerol (DAG) at the immunological synapse (IS). The mechanisms that couple DAG to the MTOC are not known. By single-cell photoactivation of the T cell antigen receptor (TCR), we found that three distinct isoforms of protein kinase C (PKC) were recruited by DAG to the IS in two steps. PKC-? and PKC-? accumulated first in a broad region of membrane, whereas PKC-? arrived later in a smaller zone. Functional experiments indicated that PKC-? was required for MTOC reorientation and that PKC-? and PKC-? operated redundantly to promote the recruitment of PKC-? and subsequent polarization responses. Our results establish a previously uncharacterized role for PKC proteins in T cell polarity.

SUBMITTER: Quann EJ

PROVIDER: S-EPMC3119370 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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A cascade of protein kinase C isozymes promotes cytoskeletal polarization in T cells.

Quann Emily J EJ Liu Xin X Altan-Bonnet Grégoire G Huse Morgan M

Nature immunology 20110522 7

Polarization of the T cell microtubule-organizing center (MTOC) toward the antigen-presenting cell (APC) is driven by the accumulation of diacylglycerol (DAG) at the immunological synapse (IS). The mechanisms that couple DAG to the MTOC are not known. By single-cell photoactivation of the T cell antigen receptor (TCR), we found that three distinct isoforms of protein kinase C (PKC) were recruited by DAG to the IS in two steps. PKC-ɛ and PKC-η accumulated first in a broad region of membrane, wher ...[more]

PMID: 21602810

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