title: Src homology domains of phospholipase C gamma1 inhibit nerve growth factor-induced differentiation of PC12 cells.
abstract: Phospholipase C gamma1 (PLC-gamma1) is phosphorylated on treatment of cells with nerve growth factor (NGF). To assess the role of PLC-gamma1 in mediating the neuronal differentiation induced by NGF treatment, we established PC12 cells that overexpress whole PLC-gamma (PLC-gamma1PC12), the SH2-SH2-SH3 domain (PLC-gamma1SH223PC12), SH2-SH2-deleted mutants (PLC-gamma1deltaSH22PC12), and SH3-deleted mutants (PLC-gamma1deltaSH3PC12). Overexpressed whole PLC-gamma1 or the SH2-SH2-SH3 domain of PLC-gamma1 stimulated cell growth and inhibited NGF-induced neurite outgrowth of PC12 cells. However, cells expressing PLC-gamma1 lacking the SH2-SH2 domain or the SH3 domain had no effect on NGF-induced neuronal differentiation. Overexpression of intact PLC-gamma1 resulted in a threefold increase in total inositol phosphate accumulation on treatment with NGF. However, overexpression of the SH2-SH2-SH3 domain of PLC-gamma1 did not alter total inositol phosphate accumulation. To investigate whether the SH2-SH2-SH3 domain of PLC-gamma1 can mediate the NGF-induced signal, tyrosine phosphorylation of the SH2-SH2-SH3 domain of PLC-gamma1 on NGF treatment was examined. The SH2-SH2-SH3 domain of PLC-gamma1 as well as intact PLC-gamma1 could be tyrosine-phosphorylated on NGF treatment. These results indicate that the overexpressed SH2-SH2-SH3 domain of PLC-gamma1 can block the differentiation of PC12 cells induced by NGF and that the inhibition appears not to be related to the lipase activity of PLC-gamma1 but to the SH2-SH2-SH3 domain of PLC-gamma1.
authors.affiliation: Department of Life Science and School of Environmental Engineering, Pohang University of Science and Technology, Kyungbuk, Republic of Korea.
authors.forename: S S
authors.initials: SS
authors.lastname: Bae
authors.forename: Y H
authors.initials: YH
authors.lastname: Lee
authors.forename: J S
authors.initials: JS
authors.lastname: Chang
authors.forename: S H
authors.initials: SH
authors.lastname: Galadari
authors.forename: Y S
authors.initials: YS
authors.lastname: Kim
authors.forename: S H
authors.initials: SH
authors.lastname: Ryu
authors.forename: P G
authors.initials: PG
authors.lastname: Suh
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D002455:Cell Division / Q000187:drug effects / Q000502:physiology; D017353:Gene Deletion; D015971:Gene Expression Regulation, Enzymologic; D007295:Inositol Phosphates / Q000096:biosynthesis; D007527:Isoenzymes / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D016296:Mutagenesis / Q000502:physiology; D009414:Nerve Growth Factors / Q000494:pharmacology*; D016501:Neurites / Q000502:physiology; D009474:Neurons / Q000166:cytology / Q000201:enzymology* / Q000648:ultrastructure; D016716:PC12 Cells; D051966:Phospholipase C gamma; D010766:Phosphorylation; D051381:Rats; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D010738:Type C Phospholipases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D014443:Tyrosine / Q000378:metabolism; D018909:src Homology Domains / Q000235:genetics*
chemical_list: D007295:Inositol Phosphates; D007527:Isoenzymes; D009414:Nerve Growth Factors; D014443:Tyrosine; D010738:Type C Phospholipases; D051966:Phospholipase C gamma