title: 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.
authors.affiliation: Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada.
authors.forename: W Rod
authors.initials: WR
authors.lastname: Hardy
authors.forename: Lingying
authors.initials: L
authors.lastname: Li
authors.forename: Zhi
authors.initials: Z
authors.lastname: Wang
authors.forename: Jiri
authors.initials: J
authors.lastname: Sedy
authors.forename: James
authors.initials: J
authors.lastname: Fawcett
authors.forename: Eric
authors.initials: E
authors.lastname: Frank
authors.forename: Jan
authors.initials: J
authors.lastname: Kucera
authors.forename: Tony
authors.initials: T
authors.lastname: Pawson
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020816:Amino Acid Motifs; D000818:Animals; D001259:Ataxia; D019706:Excitatory Postsynaptic Potentials; D005816:Genetic Complementation Test; D006321:Heart / Q000196:embryology*; D051379:Mice; D018345:Mice, Knockout; D009024:Morphogenesis; D009043:Motor Activity; D009470:Muscle Spindles / Q000196:embryology*; D018482:Muscle, Skeletal / Q000196:embryology* / Q000378:metabolism; D009154:Mutation; D032383:Myocytes, Cardiac / Q000378:metabolism*; D009475:Neurons, Afferent / Q000502:physiology; D010766:Phosphorylation; D017434:Protein Structure, Tertiary; D055765:Shc Signaling Adaptor Proteins; D015398:Signal Transduction; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; D018909:src Homology Domains
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D055765:Shc Signaling Adaptor Proteins; C528034:Shc1 protein, mouse; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1