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An active kinase domain is required for retention of PKC? at the T cell immunological synapse.

ABSTRACT: Protein kinase C? (PKC?) is a serine/threonine kinase that plays an essential role in antigen-regulated responses of T lymphocytes. Upon antigen stimulation, PKC? is rapidly recruited to the immunological synapse (IS), the region of contact between the T cell and antigen-presenting cell. This behavior is unique among T cell PKC isoforms. To define domains of PKC? required for retention at the IS, we generated deletion and point mutants of PKC?. We used quantitative imaging analysis to assess IS retention of PKC? mutants in antigen-stimulated T cell clones. Deletion of the kinase domain or site-directed mutation of a subset of known PKC? phosphorylation sites abrogated or significantly reduced IS retention, respectively. IS retention did not correlate with phosphorylation of specific PKC? residues but rather with kinase function. Thus PKC? catalytic competence is essential for stable IS retention.

SUBMITTER: Cartwright NG

PROVIDER: S-EPMC3172272 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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An active kinase domain is required for retention of PKCθ at the T cell immunological synapse.

Cartwright Natalia G NG Kashyap Anuj K AK Schaefer Brian C BC

Molecular biology of the cell 20110727 18

Protein kinase Cθ (PKCθ) is a serine/threonine kinase that plays an essential role in antigen-regulated responses of T lymphocytes. Upon antigen stimulation, PKCθ is rapidly recruited to the immunological synapse (IS), the region of contact between the T cell and antigen-presenting cell. This behavior is unique among T cell PKC isoforms. To define domains of PKCθ required for retention at the IS, we generated deletion and point mutants of PKCθ. We used quantitative imaging analysis to assess IS ...[more]

PMID: 21795397

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