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Combinatorial ShcA docking interactions support diversity in tissue morphogenesis.

ABSTRACT: Changes in protein-protein interactions may allow polypeptides to perform unexpected regulatory functions. Mammalian ShcA docking proteins have amino-terminal phosphotyrosine (pTyr) binding (PTB) and carboxyl-terminal Src homology 2 (SH2) domains, which recognize specific pTyr sites on activated receptors, and a central region with two phosphorylated tyrosine-X-asparagine (pYXN) motifs (where X represents any amino acid) that each bind the growth factor receptor-bound protein 2 (Grb2) adaptor. Phylogenetic analysis indicates that ShcA may signal through both pYXN-dependent and -independent pathways. We show that, in mice, cardiomyocyte-expressed ShcA directs mid-gestational heart development by a PTB-dependent mechanism that does not require the pYXN motifs. In contrast, the pYXN motifs are required with PTB and SH2 domains in the same ShcA molecule for the formation of muscle spindles, skeletal muscle sensory organs that regulate motor behavior. Thus, combinatorial differences in ShcA docking interactions may yield multiple signaling mechanisms to support diversity in tissue morphogenesis.

SUBMITTER: Hardy WR

PROVIDER: S-EPMC2575375 | biostudies-literature | 2007 Jul

REPOSITORIES: biostudies-literature

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Combinatorial ShcA docking interactions support diversity in tissue morphogenesis.

Hardy W Rod WR Li Lingying L Wang Zhi Z Sedy Jiri J Fawcett James J Frank Eric E Kucera Jan J Pawson Tony T

Science (New York, N.Y.) 20070701 5835

Changes in protein-protein interactions may allow polypeptides to perform unexpected regulatory functions. Mammalian ShcA docking proteins have amino-terminal phosphotyrosine (pTyr) binding (PTB) and carboxyl-terminal Src homology 2 (SH2) domains, which recognize specific pTyr sites on activated receptors, and a central region with two phosphorylated tyrosine-X-asparagine (pYXN) motifs (where X represents any amino acid) that each bind the growth factor receptor-bound protein 2 (Grb2) adaptor. P ...[more]

PMID: 17626887

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Combinatorial ShcA docking interactions support diversity in tissue morphogenesis.

Publications

Combinatorial ShcA docking interactions support diversity in tissue morphogenesis.

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