Journal
JOURNAL OF MOLECULAR BIOLOGY
Volume 314, Issue 1, Pages 129-138Publisher
ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD
DOI: 10.1006/jmbi.2001.5126
Keywords
protein tyrosine kinase; SH3 domain; Src-family kinases; heteronuclear NMR
Categories
Funding
- NCI NIH HHS [CA-37244] Funding Source: Medline
- NIGMS NIH HHS [R01 GM047021, GM-47021, R01 GM047021-12S1] Funding Source: Medline
- PHS HHS [F03744] Funding Source: Medline
Ask authors/readers for more resources
Csk (C-terminal Src kinase), a protein tyrosine kinase, consisting of the Src homology 2 and 3 (SH2 and SH3) domains and a catalytic domain, phosphorylates the C-terminal tail of Src-family members, resulting in downregulation of the Src family kinase activity. The Src family kinases share 37% homology with Csk but, unlike Src-family kinases, the catalytic domain of Csk alone is weakly active and can be stimulated in trans by interacting with the Csk-SH3 domain, suggesting a mode of intradomain regulation different from that of Src family kinases. The structural determinants of this intermolecular interaction were studied by nuclear magnetic resonance (NMR) and site-directed mutagenesis techniques. Chemical shift perturbation of backbone nuclei (H' and N-15) has been used to map the Csk catalytic domain binding site on the Csk-SH3. The experimentally determined interaction surface includes three structural elements: th N-terminal tail, a small part of the RT-loop, and the C-terminal SH3-SH2 linker. Site-directed mutagenesis revealed that mutations in the SH3-SH2 linker of the wild-type Csk decrease Csk kinase activity up to fivefold, whereas mutations in the RT-loop left Csk kinase activity largely unaffected. We conclude that the SH3-SH2 linker plays a major role in the activation of the Csk catalytic domain. (C) 2001 Academic Press.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available