Colony-stimulating factor 1 (CSF-1) is involved in an autocrine growth control of rat myogenic cells.
Colony stimulating factor-1 (CSF-1) and the CSF-1 receptor (the c-fms proto-oncogene product) are expressed during the proliferation of the L6 alpha 1 rat myogenic cell line and both are down-regulated during the differentiation to myotubes. Biologically active CSF-1 was shown to be secreted into the culture medium by L6 alpha 1 myoblasts and while they could not bind CSF-1, evidence was obtained for cell surface receptor-CSF-1 complexes. It was not possible to block the L6 alpha 1 proliferation by incubation with anti-CSF-1 antiserum or suramin. However, in L6 alpha 1 myoblasts that were stably transfected with an inducible anti-fms antisense construct, both c-fms protein expression and cell proliferation were more rapidly inhibited under induction and differentiation conditions than parental cells. Furthermore, under these conditions, the c-fms antisense transfected cells also entered myogenic differentiation more rapidly. These results suggest that autocrine regulation by CSF-1 that is intracellular may play a role in the proliferation of muscle cells and that its down-regulation leads to, and may be an obligatory step in, myogenesis.
Borycki
A G
AG
Laboratoire de Cancérologie Expérimentale, UA 1158, URA 126 CNRS, Institut Gustave Roussy, Villejuif, France.
Smadja
F
F
Stanley
R
R
Leibovitch
S A
SA
D000818:Animals; D002455:Cell Division / Q000502:physiology*; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D017077:Culture Media, Conditioned; D015342:DNA Probes; D015870:Gene Expression / Q000187:drug effects; D007700:Kinetics; D016173:Macrophage Colony-Stimulating Factor / Q000096:biosynthesis / Q000378:metabolism*; D008264:Macrophages; D051379:Mice; D009132:Muscles; D016372:RNA, Antisense / Q000378:metabolism; D051381:Rats; D016186:Receptor, Macrophage Colony-Stimulating Factor / Q000096:biosynthesis / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism
D017077:Culture Media, Conditioned; D015342:DNA Probes; D016372:RNA, Antisense; D011994:Recombinant Proteins; D016173:Macrophage Colony-Stimulating Factor; D016186:Receptor, Macrophage Colony-Stimulating Factor