Essential role of the tyrosine kinase substrate phospholipase C-γ1 in mammalian growth and development

Essential role of the tyrosine kinase substrate phospholipase C-γ1 in mammalian growth and development

Departments of ^*Biochemistry, ^†Cell Biology, ^‡Molecular Physiology and Biophysics, and ^§Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232

Abstract

The activation of many tyrosine kinases leads to the phosphorylation and activation of phospholipase C-γ1 (PLC-γ1). To examine the biological function of this protein, homologous recombination has been used to selectively disrupt the Plcg1 gene in mice. Homozygous disruption of Plcg1 results in embryonic lethality at approximately embryonic day (E) 9.0. Histological analysis indicates that Plcg1 (−/−) embryos appear normal at E 8.5 but fail to continue normal development and growth beyond E 8.5–E9.0. These results clearly demonstrate that PLC-γ1 with, by inference, its capacity to mobilize second messenger molecules is an essential signal transducing molecule whose absence is not compensated by other signaling pathways or other genes encoding PLC isozymes.

Footnotes

↵ ¶ To whom reprint requests should be addressed.
Stanley Cohen, Vanderbilt University School of Medicine, Nashville, TN
ABBREVIATIONS:

PLC,

phospholipase C;

ES,

embryonic stem;

TV,

targeting vector;

MEF,

mouse embryonic fibroblasts;

E,

embryonic day