Signaling by phosphoinositide-3,4,5-trisphosphate through proteins containing pleckstrin and Sec7 homology domains
AuthorsKlarlund, Jes K.
Guilherme, Adilson L.
Virbasius, Joseph V.
Czech, Michael P.
UMass Chan AffiliationsDepartment of Biochemistry and Molecular Biology
Program in Molecular Medicine
ADP-Ribosylation Factor 1
Amino Acid Sequence
Cell Adhesion Molecules
*Guanine Nucleotide Exchange Factors
Molecular Sequence Data
Phosphotransferases (Alcohol Group Acceptor)
Receptors, Cytoplasmic and Nuclear
Recombinant Fusion Proteins
Sequence Homology, Amino Acid
Medicine and Health Sciences
MetadataShow full item record
AbstractSignal transmission by many cell surface receptors results in the activation of phosphoinositide (PI) 3-kinases that phosphorylate the 3' position of polyphosphoinositides. From a screen for mouse proteins that bind phosphoinositides, the protein GRP1was identified. GRP1 binds phosphatidylinositol-3,4,5-trisphosphate [PtdIns(3,4, 5)P3] through a pleckstrin homology (PH) domain and displays a region of high sequence similarity to the yeast Sec7 protein. The PH domain of the closely related protein cytohesin-1, which, through its Sec7 homology domain, regulates integrin beta2 and catalyzes guanine nucleotide exchange of the small guanine nucleotide-binding protein ARF1, was also found to specifically bind PtdIns(3,4,5)P3. GRP1 and cytohesin-1 appear to connect receptor-activated PI 3-kinase signaling pathways with proteins that mediate biological responses such as cell adhesion and membrane trafficking.
Science. 1997 Mar 28;275(5308):1927-30.
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/38802
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