Expression of PDGF A-Chain and β-Receptor Genes during Rat Myoblast Differentiation

• Published in: The Journal of cell biology 1990-05, Vol.110 (5), p.1665-1672
• Main Authors: Jin, Pei, Rahm, Magnus, Claesson-Welsh, Lena, Heldin, Carl-Henrik, Sejersen, Thomas
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Cell Differentiation - physiology; Cell Division - physiology; Cell growth; Cell Line; Cell lines; Cells; DNA; DNA Replication - physiology; Fluorescent Antibody Technique; Fundamental and applied biological sciences. Psychology; Gene expression; Gene Expression Regulation - physiology; Genes; Molecular and cellular biology; Molecular genetics; Muscle fibers; Muscle tissues; Muscles - cytology; Muscles - metabolism; Myoblasts; Platelet-Derived Growth Factor - biosynthesis; Platelet-Derived Growth Factor - genetics; Poly A - metabolism; Proto-Oncogene Proteins - biosynthesis; Proto-Oncogene Proteins c-fos; Rats; Receptors; Receptors, Cell Surface - biosynthesis; Receptors, Cell Surface - genetics; Receptors, Platelet-Derived Growth Factor; RNA; RNA, Messenger - metabolism
• ISSN: 0021-9525; 1540-8140
• DOI: 10.1083/jcb.110.5.1665

L6J1 rat myoblasts and rat skeletal muscle were studied for expression of mRNAs encoding PDGF A-chain, PDGF B-chain, PDGF α-receptor, and PDGF β-receptor during in vitro and in vivo myoblast differentiation. RNA blot hybridizations demonstrated expression of the PDGF A-chain gene and the PDGF β-receptor gene in L6J1 myoblasts and in crude muscle tissue isolated from developing rats. Transcripts of the PDGF A-chain were identified at all examined stages of in vitro and in vivo myogenic differentiation. Expression of the PDGF β-receptor gene decreased in differentiated myotubes of L6J1 cells and in rat adult muscle tissue. Receptor binding assays demonstrated specific binding of PDGF-BB, but not -AA, to exponentially proliferating L6J1 myoblasts and to terminally differentiated L6J1 myotubes. The binding per cell nucleus was higher in exponentially proliferating myoblasts than in differentiated L6J1 myotubes. In serum free medium PDGF-BB was shown to increase c-fos protooncogene immunoreactivity in L6J1 myoblasts. In the presence of 0.5% FCS, PDGF-BB increased DNA synthesis in L6J1 myoblasts, while PDGF-AA showed no such effect. Differentiation, as monitored by myotube formation, was reduced in PDGF-BB-treated cultures. The possible role of PDGF in myoblast proliferation and differentiation is discussed.