Src homology region

Moran, M. F., Koch, C. A., Anderson, D., Ellis, C., England, L., Martin, G. S., and Pawson, T. (1990). Src homology region 2 domains direct protein-protein interactions in signal transduction, Proc Natl Acad Sci U S A 87,8622-6. 

A structural domain consists of 100-150 residues in various combinations of motifs. Often a domain is characterized by some interesting structural feature an unusual abundance of a particular amino acid (e.g., a prollne-rich domain, an acidic domain), sequences common to (conserved in) many proteins (e.g., SH3, or Src homology region 3), or a particular secondary-structure motif (e.g., zinc-finger motif in the kringle domain). 

Hirai, H. Varmus, H.E. (1990). Mutations in src homology regions 2 and 3 of activated chicken c-src that result in preferential transformation of mouse and chicken cells. Proc. Natl Acad. Scl USA, 87, 8592-6. 

All PLC isozymes have conserved catalytic domains designated X and Y, and a C2 domain similar to that in cPLA2 (Fig. 2). In addition, the (3, y and 8 isozymes have pleckstrin homology (PH) domains and EF-hand domains located in theN-teiminal region. The y isozymes differ in that they have Src homology domains (SH2 and SH3) and an additional PH domain split by the SH domains. The (3 and y isozymes are of140-155 kDa mass, whereas the 8 isozymes are smaller (85 kDa) and the o isozyme is larger (240 kDa). 

Many non-receptor tyrosine kinases have been identified as products of retrovirally encoded oncogenes. Non-receptor tyrosine kinases can be divided into two groups transmembrane and cytosolic families. The c-src tyrosine kinase is the prototype of the cytosolic tyrosine kinases. Regions within these non-receptor tyrosine kinases share homology with the Src kinase, known as Src homology 2 and 3 (SH2 and SH3) domains, and mediate protein-protein interactions between the receptor tyrosine kinases and the intracellular targets (reviewed in Cantley et al., 1991 Pawson and Gish, 1992 Mayer and Baltimore, 1993). 

Fig. 8.14 Domain structure of cytoplasmic tyrosine kinases. Linear representation of the domain structure of selected cytoplasmic tyrosine kinases. Details of the cytoplasmic tyrosine kinases Src 8.3.2 Jak, Tyk 11.1.5 Zap-70 11.2.2 Fak 11.3 JH Jak homology region. According to Taniguchi, (1995).

The Src homology 3 (SH3) domain of a-spectrin was the first SH3 domain structure to be solved (Musacchio et al., 1992). The domain was initially identified as regions of similar sequence found within signaling proteins, such as the Src family of tyrosine kinases, the Crk adaptor... 

The recruited proteins may have quite different functions, but their structures often have in common that they contain consensus sequences, 50-100 amino acids long, although the adjacent regions may be quite different. Among sequences recognizing phosphot5Tosyls are the Src homology domain, SH2, and the PTBs. 

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