PDGF-BB AND IGF-I USE DIFFERENT SIGNALING PATHWAYS TO INDUCE NaK-ATPase SUBUNITS IN CULTURED RAT THORACIC AORTIC SMOOTH MUSCLE CELLS

✍ Scribed by Chu S. Lo

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 120 KB
• Volume: 23
• Category: Article
• ISSN: 1065-6995
• DOI: 10.1006/cbir.1999.0345

✦ Synopsis

Na + +K + )-adenosine triphosphatase (NaK-ATPase), an ubiquitous membrane transport protein consisting of and subunits, regulates Na + /K + fluxes and maintains many vital physiological functions, including cell growth. Results have indicated that platelet-derived growth factor (PDGF) and insulin-like growth factor-I (IGF-I) both enhance NaK-ATPase subunits. Genistein, an inhibitor of tyrosine phosphorylation, inhibits serum-and PDGF-BB-induced NaK-ATPase 1 subunit protein levels without inhibiting IGF-I-induced NaK-ATPase 1 subunit protein levels. These results indicate that PDGF-BB and IGF-I utilize separate signaling pathways to induce the synthesis of NaK-ATPase 1 subunits. In addition, genistein failed to inhibit PDGF-BBstimulated NaK-ATPase 1 subunit levels, suggesting that two separate pathways are involved to induce the synthesis of the NaK-ATPase 1 and 1 subunits, respectively.