Control of SHB gene expression by protein phosphorylation

• Published in: Cellular signalling Vol. 8; no. 1; pp. 55 - 58
• Main Authors: Lavergne, Corinne, Mares, Jaroslav, Karlsson, Torbjörn, Bréant, Bernadette, Welsh, Michael
• Format: Journal Article
• Language: English
• Published: England Elsevier Inc 1996
• Subjects: 3T3 Cells - drug effects; Animals; Enzyme Inhibitors - pharmacology; Ethers, Cyclic - pharmacology; Gene expression; Gene Expression Regulation - physiology; Genistein; Isoflavones - pharmacology; Mice; Mitogenic signal-transduction; Nitriles - pharmacology; Okadaic Acid; Phosphorylation - drug effects; Platelet-Derived Growth Factor - pharmacology; Protein kinases; Protein Processing, Post-Translational; Proto-Oncogene Proteins - biosynthesis; Proto-Oncogene Proteins - genetics; Proto-Oncogene Proteins - physiology; Proto-Oncogene Proteins c-sis; RNA, Messenger - biosynthesis; Shb; Signal Transduction - physiology; Src Homology 2 domain; Tetradecanoylphorbol Acetate - pharmacology; Tyrphostins; Src Homology 2 domain; Mitogenic signal-transduction; Gene expression; Shb; Protein kinases
• ISSN: 0898-6568; 1873-3913; 1873-3913
• DOI: 10.1016/0898-6568(95)02019-5

To increase our understanding of the role of the Src homology 2 (SH2) domain-containing protein Shb in the mitogenic signal transduction, Shb mRNA contents were determined in the fibroblast-like NIH3T3 cells and the insulin producing βTC-1 cells under various conditions. In NIH3T3 cells, the serine/ threonine phosphatase inhibitor okadaic acid and the tyrosine kinase inhibitor genistein increased Shb mRNA contents, the protein kinase C activating phorbol ester 12-O-tetradecanoyl 13-acetate (TPA) decreased the Shb mRNA content, whereas the tyrosine kinase inhibitor tyrphostin 25 and the mitogen platelet-derived growth factor (PDGF-BB) had no effect. In βTC-1 cells, okadaic acid and genistein increased the Shb mRNA content, whereas tyrphostin 25 and serum were without effect. Okadaic acid and genistein decreased the rates of βTC-1 cell DNA synthesis. It is concluded that expression of the SHB gene is under a complex mode of regulation involving at least three different protein kinases. As a consequence of this, it is likely that SHB gene expression is significantly modulated by conditions of specific activation of certain pathways, whereas its expression appears little influenced by serum and a mitogen.