Activation of CD4 T cells by Raf-independent effectors of Ras
AUTOR(ES)
Czyzyk, Jan
FONTE
The National Academy of Sciences
RESUMO
Small GTPase Ras is capable of mediating activation in T lymphocytes by using Raf kinase-dependent signaling pathway. Other effectors of Ras exist, however, suggesting that targets of Ras alternative to Raf may also contribute to T cell functions. Here we demonstrate that RasV12G37 mutant that fails to bind Raf, potently increases intracellular calcium concentration and cytokine production in primary antigen-stimulated T cells. From three known effectors which retain the ability to interact with RasV12G37, overexpression of phospholipase C ɛ but not that of RIN1 or Ral guanine nucleotide exchange factors enhanced cytokine and nuclear factor-activated T cell reporter T cell responses. Hence T cell activation can be critically regulated by the Ras effector pathway independent from Raf that can be mimicked by phospholipase C ɛ.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=156316Documentos Relacionados
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