Synip: a novel insulin-regulated syntaxin 4-binding protein mediating GLUT4 translocation in adipocytes.
Insulin-stimulated glucose transport and GLUT4 translocation require regulated interactions between the v-SNARE, VAMP2, and the t-SNARE, syntaxin 4. We have isolated a novel syntaxin 4-binding protein, Synip, which specifically interacts with syntaxin 4. Insulin induces a dissociation of the Synip:syntaxin 4 complex due to an apparent decrease in the binding affinity of Synip for syntaxin 4. In contrast, the carboxyterminal domain of Synip does not dissociate from syntaxin 4 in response to insulin stimulation but inhibits glucose transport and GLUT4 translocation. These data implicate Synip as an insulin-regulated syntaxin 4-binding protein directly involved in the control of glucose transport and GLUT4 vesicle translocation.
Pubmed ID: 10394363 RIS Download
Adipocytes | Amino Acid Sequence | Animals | Binding, Competitive | Biological Transport | Carrier Proteins | Cell Line | Cloning, Molecular | Cricetinae | Genes, Dominant | Glucose | Glucose Transporter Type 4 | Humans | Insulin | Membrane Proteins | Mice | Molecular Sequence Data | Monosaccharide Transport Proteins | Muscle Proteins | Mutation | Organelles | Protein Binding | Qa-SNARE Proteins | Qb-SNARE Proteins | Qc-SNARE Proteins | R-SNARE Proteins | RNA, Messenger | Vesicular Transport Proteins | Yeasts