Transcription factors NFAT, NFkB, Oct-1, AP1, c-myc, nur77 etc.

Transcription factors NFAT, NFkB, Oct-1, AP1, c-myc, nur77 etc.

Gene expression

FIGURE 17-2 Simplified schematic representation of signal transduction events that occur in T cells following antigen recognition. Reproduced with permission from Kisielow, P. (1995). Apoptosis in intrathymic T-cell development. In "Apoptosis and the Immune Response" (C. D. Gregory, ed.), pp. 13-53. Wiley-Liss, New York.

initiated by the a/3 T-cell receptor. Tyrosine phosphorylation is called into play, which includes the ¿"-chain of the T-cell receptor complex. For reference, a diagrammatic representation of the T-cell receptor signal transduction is given in Figure 17-2. Phospholipase Cyi is also phosphorylated, reflecting the elevated activities of Fyn and Lck tyrosine kinases. The ¿"-chain of the T-cell receptor then associates with the ZAP-70 tyrosine kinase (Figure 17-2). Activation of phospholipase C leads to hydrolysis of phosphatidylinositol 4,5-biphos-phate (PIP2), generating 1,2-diacylglycerol (DAG) and inositol triphosphate (IP3), which lead to the activation of protein kinase C (PKC). Intracellular Ca2+ levels are increased by IP3. Potential PKC targets include p21ras, its GTPase activity controlling GAP and NF1 proteins, and raf and MAP kinases. Calcium increases activate calcineurin, a Ca2+ calmodulin-dependent protein phosphatase. NFAT, a transcriptional regulator of IL-2 gene expression, is a target of calcineurin that can activate NFAT by dephosphorylation. NF-kB and AP-1 can be targets of the T-cell receptor signal transduction pathway. Oct-1, c-myc, and nur 77 may also be involved.

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Cure Tennis Elbow Without Surgery

Cure Tennis Elbow Without Surgery

Everything you wanted to know about. How To Cure Tennis Elbow. Are you an athlete who suffers from tennis elbow? Contrary to popular opinion, most people who suffer from tennis elbow do not even play tennis. They get this condition, which is a torn tendon in the elbow, from the strain of using the same motions with the arm, repeatedly. If you have tennis elbow, you understand how the pain can disrupt your day.

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