Publication Date:
1990-03-02
Description:
Several immunologically distinct isozymes of inositol phospholipid-specific phospholipase C (PLC) have been purified from bovine brain. Murine NIH 3T3 fibroblasts were found to express PLC-gamma, but the expression of PLC-beta was barely detectable by radioimmunoassay or protein immunoblot. A mixture of monoclonal antibodies was identified that neutralizes the biological activity of both endogenous and injected purified PLC-gamma. When co-injected with oncogenic Ras protein or PLC-gamma, this mixture of antibodies inhibited the induction of DNA synthesis that characteristically results from the injection of these proteins into quiescent 3T3 cells. However, when oncogenic Ras protein or PLC-gamma was co-injected with a neutralizing monoclonal antibody to Ras, only the DNA synthesis induced by the Ras protein was inhibited--that induced by PLC was unaffected. These results suggest that the Ras protein is an upstream effector of PLC activity in phosphoinositide-specific signal transduction and that PLC-gamma activity is necessary for Ras-mediated induction of DNA synthesis.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Smith, M R -- Liu, Y L -- Kim, H -- Rhee, S G -- Kung, H F -- N01-CO-74102/CO/NCI NIH HHS/ -- New York, N.Y. -- Science. 1990 Mar 2;247(4946):1074-7.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Biological Carcinogenesis and Development Program, National Cancer Institute-Frederick Cancer Research Facility, MD 21701.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/2408147" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Antibodies, Monoclonal/immunology
;
Cell Line
;
DNA/*biosynthesis
;
Fibroblasts
;
Growth Substances/pharmacology
;
Hybridomas
;
Immunoblotting
;
Interphase
;
Isoenzymes/immunology/*metabolism
;
Microinjections
;
Oncogene Protein p21(ras)/immunology/*pharmacology
;
Radioimmunoassay
;
Signal Transduction
;
Type C Phospholipases/immunology/*metabolism/pharmacology
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
