Repression of the CSF-1 receptor (c-fms proto-oncogene product) by antisense transfection induces G1-growth arrest in L6 alpha 1 rat myoblasts.
Colony Stimulating Factor (CSF-1) and the CSF-1 receptor (the c-fms product) are expressed during the proliferation of L6 alpha 1 rat myogenic cell line and both are down regulated during the formation of myotubes. In this study, we demonstrated that the expression of c-fms antisense RNA in stably transfected myoblasts repressed the CSF-1 receptor (c-fms protein) and induced a G1-growth arrest. Expression of the cyclin genes, that control passage through the G1 phase and in particular the cyclins identified as genes induced late in G1 by CSF-1 in mouse macrophages was studied in comparative Northern blot analyses of RNAs of subpopulations prepared by centrifugal elutriation of L6 alpha 1 myoblasts and induced Antifms D5 cells expressing c-fms antisense RNA. Repression of the CSF-1 receptor (c-fms product) did not affect cyclins A, B and G expression during the cell cycle. However, D-type cyclins and, at a lesser extend, cyclin E expression were dramatically altered specifically during the late G1 and early S phases, in Antifms D5 cells. These results suggest a role for the CSF-1/c-fms autocrine loop in the control of the proliferation of L6 alpha 1 rat myogenic cell line at the G1/S boundary via the D-type and E cyclins expression.
Borycki
A G
AG
Laboratoire de Cancérologie Expérimentale, UA1158, URA126 CNRS, Institut Gustave Roussy, Villejuif, France.
Foucrier
J
J
Saffar
L
L
Leibovitch
S A
SA
D000818:Animals; D002453:Cell Cycle; D002460:Cell Line; D002469:Cell Separation; D002478:Cells, Cultured; D016213:Cyclins / Q000235:genetics / Q000378:metabolism*; D005434:Flow Cytometry; D015870:Gene Expression; D066298:In Vitro Techniques; D016173:Macrophage Colony-Stimulating Factor / Q000502:physiology*; D009132:Muscles / Q000166:cytology*; D016372:RNA, Antisense; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D016186:Receptor, Macrophage Colony-Stimulating Factor / Q000235:genetics / Q000502:physiology*; D014162:Transfection
D016213:Cyclins; D016372:RNA, Antisense; D012333:RNA, Messenger; D016173:Macrophage Colony-Stimulating Factor; D016186:Receptor, Macrophage Colony-Stimulating Factor