PKD2 interacts with Lck and regulates NFAT activity in T cells

Department of Life Science and Biotechnology, Shanghai Jiaotong University, 1954 Huashan Road, Shanghai, 200030, China.
BMB reports (Impact Factor: 2.6). 02/2009; 42(1):35-40. DOI: 10.5483/BMBRep.2009.42.1.035
Source: PubMed


Protein kinase D2 (PKD2) is a member of the PKD serine/threonine protein kinase family that has been implicated in the regulation of a variety of cellular processes including proliferation, survival, protein trafficking and immune response. In the present study, we report a novel interaction between PKD2 and Lck, a member of the Src tyrosine protein kinase family that is predominantly expressed in T cells. This interaction involved the C-terminal kinase domains of both PKD2 and Lck. Moreover, co-expression of Lck enhanced the tyrosine phosphorylation of PKD2 and increased its kinase activity. Finally, we report that PKD2 enhanced T cell receptor (TCR)-induced nuclear factor of T cell (NFAT) activity in Jurkat T cells. These results suggested that Lck regulated the activity of PKD2 by tyrosine phosphorylation, which in turn may have modulated the physiological functions of PKD2 during TCR-induced T cell activation. [BMB reports 2009; 42(1): 35-40].

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