Sandbox Reserved 1124: Difference between revisions
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<scene name='71/719865/C-terminal_sh3_domains/1'>The C-terminal SH3 domains</scene> .... | <scene name='71/719865/C-terminal_sh3_domains/1'>The C-terminal SH3 domains</scene> .... | ||
==Function== | ==Function== | ||
=== MAP kinases pathway === | |||
In the cytosol, Grb2 is bound to the guanine nucleotide exchange factor SOS-1 via its SH3 domain. Then, this complexe is recruited to the plasmic membrane to be close the Ras protein. This protein is a small GTPase which is in an inactive state when it is bound to GDP. However, the exchange of GDP for GTP actives it allowing the bond and the activation of Raf 1, a serine/threonine protein kinase. A cascade of kinase phosphorylation is then initiated. Indeed, Raf 1 phosphorylates MEK1 or MEK 2 which in turn phosphorylate ERK1 or ERK2. Finally, these MAP kinases allow the translocation of transcription factors to the nucleus and their phosphorylation. Such as STAT 1 or Elk-1. | In the cytosol, Grb2 is bound to the guanine nucleotide exchange factor SOS-1 via its SH3 domain. Then, this complexe is recruited to the plasmic membrane to be close the Ras protein. This protein is a small GTPase which is in an inactive state when it is bound to GDP. However, the exchange of GDP for GTP actives it allowing the bond and the activation of Raf 1, a serine/threonine protein kinase. A cascade of kinase phosphorylation is then initiated. Indeed, Raf 1 phosphorylates MEK1 or MEK 2 which in turn phosphorylate ERK1 or ERK2. Finally, these MAP kinases allow the translocation of transcription factors to the nucleus and their phosphorylation. Such as STAT 1 or Elk-1. | ||
When TCR are stimulated, the membrane protein called p36-38 is phosphorylated in the T cells. Then, the phosphorylated tyrosines bind the SH2 domains of Grb2 whereas the SH3 domains are bound to Vav proteins. These interactions allow the T cell proliferation, the calcium flux in these cells and the MAP kinase activation. | When TCR are stimulated, the membrane protein called p36-38 is phosphorylated in the T cells. Then, the phosphorylated tyrosines bind the SH2 domains of Grb2 whereas the SH3 domains are bound to Vav proteins. These interactions allow the T cell proliferation, the calcium flux in these cells and the MAP kinase activation. | ||
