Phosphotyrosine-independent binding of a 62-kDa protein to the src homology 2 (SH2) domain of p56lck and its regulation by phosphorylation of Ser-59 in the lck unique N-terminal region.
Article Details
- CitationCopy to clipboard
Park I, Chung J, Walsh CT, Yun Y, Strominger JL, Shin J
Phosphotyrosine-independent binding of a 62-kDa protein to the src homology 2 (SH2) domain of p56lck and its regulation by phosphorylation of Ser-59 in the lck unique N-terminal region.
Proc Natl Acad Sci U S A. 1995 Dec 19;92(26):12338-42.
- PubMed ID
- 8618896 [ View in PubMed]
- Abstract
A previously undescribed 62-kDa protein (p62) that does not contain phosphotyrosine but, nevertheless, binds specifically to the isolated src homology 2 (SH2) domain of p56lck has been identified. The additional presence of the unique N-terminal region of p56lck prevents p62 binding to the SH2 domain. However, phosphorylation at Ser-59 (or alternatively, its mutation to Glu) reverses the inhibition and allows interaction of the p56lck SH2 domain with p62. Moreover, p62 is associated with a serine/threonine kinase activity and also binds to ras GTPase-activating protein, a negative regulator of the ras signaling pathway. Thus, phosphotyrosine-independent binding of p62 to the p56lck SH2 domain appears to provide an alternative pathway for p56lck signaling that is regulated by Ser-59 phosphorylation.