Osteoclast differentiation factor modulates cell cycle machinery and causes a delay in s phase progression in RAW264 cells.
Osteoclast differentiation factor (ODF) induces differentiation of mouse RAW264 cells to mature osteoclasts. To understand the mechanism controlling a coupling between withdrawal from the cell cycle and differentiation, we examined cell cycle progression and expression profiles of cell cycle regulatory genes at the initial phase in committed cells. ODF rapidly converted the hyperphosphorylated form of the retinoblastoma protein (pRb) into the hypophosphorylated form. The p21 protein was induced by ODF treatment in the same time course with that of dephosphorylation of pRb, followed by a sharp decline. After this period, a delayed entry of the S phase started accompanying the induction of CycD3 and cdk6 in differentiating cells. Hydroxyurea treatment indicated that the S phase entry was a prerequisite for osteoclast formation. Thus, ODF induces pleiotropic effects on cell cycle regulatory genes in RAW264 cells during the initial phase of the differentiation process to osteoclasts.
Graduate School of Biological Sciences, Nara Institute of Science and Technology, Nara, Ikoma, 630-0101, Japan.
E
E
Meiyanto
M
M
Hoshijima
T
T
Ogawa
N
N
Ishida
T
T
Takeya
D000818:Animals; D002352:Carrier Proteins / Q000502:physiology*; D002453:Cell Cycle / Q000502:physiology*; D018797:Cell Cycle Proteins / Q000235:genetics; D002454:Cell Differentiation; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D020869:Gene Expression Profiling; D006918:Hydroxyurea / Q000494:pharmacology; D008562:Membrane Glycoproteins / Q000502:physiology*; D051379:Mice; D010010:Osteoclasts / Q000166:cytology* / Q000187:drug effects; D010766:Phosphorylation; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D016160:Retinoblastoma Protein / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016196:S Phase
D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D008562:Membrane Glycoproteins; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D016160:Retinoblastoma Protein; C505687:Tnfrsf11a protein, mouse; C505689:Tnfsf11 protein, mouse; D006918:Hydroxyurea