Expression of guanine nucleotide binding proteins, Gs and Gi, in mRNAs in epidermal keratinocytes

✍ Scribed by H. Takahashi; N. Miyokawa; M. Katagiri; H. Iizuka

• Publisher: Springer-Verlag
• Year: 1990
• Tongue: English
• Weight: 952 KB
• Volume: 282
• Category: Article
• ISSN: 0340-3696
• DOI: 10.1007/bf00372090

✦ Synopsis

The stimulation or inhibition of adenylate cyclase by hormones and chemicals is mediated by the stimulatory or inhibitory guanine nucleotide-binding proteins, Gs and Gi respectively. Although the presence of these G-proteins in the epidermis has been suggested, no direct information regarding their nature has been available. Using cDNAs for these G-proteins as a probe, we investigated the nature of the G-proteins of various keratinocytes. FRSK cells, a cell line derived from fetal rat epidermal cells, and SV-40-transformed human epidermal cells, both of which are highly proliferative keratinocytes, contained mRNAs for both Gs-~ and two Gi-~ proteins (Gi-2~ and -3~). No evidence for the presence of Gi-l~ or Go-~ was obtained. Normal human or pig epidermis had a relatively small amount of mRNAs for these G-proteins in the stable (hypoproliferative) condition. Tape-strippinginduced, and UVB-induced hyperproliferative epidermis contained an increased amount of these G-protein messages. However, all Gs-~, Gi-2~ and -3~, as well as ]~-actin mRNAs, were increased to a similar extent, and no specific expression of G-protein messages could be detected in the hyperproliferative epidermis.