Inositol 5'-phosphatase, SHIP1 interacts with phospholipase C-gamma1 and modulates EGF-induced PLC activity.
Phospholipase C-gamma1, containing two SH2 and one SH3 domains which participate in the interaction between signaling molecules, plays a significant role in the growth factor-induced signal transduction. However, the role of the SH domains in the growth factor-induced PLC-gamma1 regulation is unclear. By peptide-mass fingerprinting analysis, we have identified SHIP1 as the binding protein for the SH3 domain of PLC-gamma1. SHIP1 was co-immunoprecipitated with PLC-gamma1 and potentiated EGF-induced PLC-gamma1 activation. However, inositol 5'-phosphatase activity of SHIP1 was not required for the potentiation of EGF-induced PLC-gamma1 activation. Taken together, these results suggest that SHIP1 may function as an adaptor protein which can potentiate EGF-induced PLC-gamma1 activation without regards to its inositol 5'-phosphatase activity.
Song
Minseok
M
Department of Life Science, Division of Molecular and Life Science, Postech Biotech Center, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea.
Kim
Myung Jong
MJ
Ha
Sanghoon
S
Park
Jong Bae
JB
Ryu
Sung Ho
SH
Suh
Pann-Ghill
PG
D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D000818:Animals; D019556:COS Cells / Q000201:enzymology; D002522:Chlorocebus aethiops; D004789:Enzyme Activation; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D047468:Immunoprecipitation; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D000072181:Inositol Polyphosphate 5-Phosphatases; D008969:Molecular Sequence Data; D051966:Phospholipase C gamma; D010744:Phosphoric Monoester Hydrolases / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D015398:Signal Transduction; D010738:Type C Phospholipases / Q000737:chemistry / Q000378:metabolism*; D018909:src Homology Domains / Q000502:physiology*
D048868:Adaptor Proteins, Signal Transducing; D004815:Epidermal Growth Factor; D015544:Inositol 1,4,5-Trisphosphate; D010744:Phosphoric Monoester Hydrolases; D000072181:Inositol Polyphosphate 5-Phosphatases; D010738:Type C Phospholipases; D051966:Phospholipase C gamma