IkappaBalpha regulates Hes1 in osteoclast differentiation and resorption.
During osteoclast differentiation and resorption, both NF-kappaB and Notch signalling are activated. This study defines the mechanism about the influence of NFkappaB on Notch. To this end, IkappaBalphaM and Wild-type-IkappaBalpha were transfected into RAW 264.7 cells. The number of cells that differentiated into osteoclasts was quantified. The resorption area was measured. NF-kappaB transcriptional activity was determined by EMSA. Hes1, DC-STAMP and MMP-9 mRNA expression levels were determined by RT-PCR. Hes1 protein expression was determined by western blots. ChIP was used to study binding of IkappaBalpha to the Hes1 promoter. NF-kappaB inactivation inhibited the differentiation and resorption ability of osteoclasts. Compared with Wild-type cells, NF-kappaB inactivation resulted in an up-regulation of Hes1 expression, and a down-regulation of DC-STAMP and MMP-9 expression. Moreover, in response to RANKL, NF-kappaB inactivation resulted in a down-regulation of DC-STAMP and MMP-9 expression compared with Wild-type cells. The Hes1 promoter was detected by ChIP using IkappaBalpha antibody. In conclusion, our data suggest IkappaBalpha regulates Hes1-mediated activity in osteoclast differentiation and resorption, which supports a cross-talk between NF-kappaB and Notch in osteoclast activity.
Department of Orthodontics, University Medical Centre Groningen, University of Groningen, The Netherlands.
Li
L
Duan
Paul
P
de Vos
Mingwen
M
Fan
Yijin
Y
Ren
D000818:Animals; D001483:Base Sequence; D051792:Basic Helix-Loop-Helix Proteins / Q000502:physiology*; D001862:Bone Resorption; D002454:Cell Differentiation / Q000502:physiology*; D002460:Cell Line; D002478:Cells, Cultured; D047369:Chromatin Immunoprecipitation; D017931:DNA Primers; D024202:Electrophoretic Mobility Shift Assay; D018398:Homeodomain Proteins / Q000502:physiology*; D006801:Humans; D020672:I-kappa B Proteins / Q000502:physiology*; D051379:Mice; D000072000:NF-KappaB Inhibitor alpha; D010010:Osteoclasts / Q000166:cytology*; D016133:Polymerase Chain Reaction; D000072056:Transcription Factor HES-1
D051792:Basic Helix-Loop-Helix Proteins; D017931:DNA Primers; D018398:Homeodomain Proteins; D020672:I-kappa B Proteins; D000072000:NF-KappaB Inhibitor alpha; D000072056:Transcription Factor HES-1; C000606204:NFKBIA protein, human; C000606205:Nfkbia protein, mouse; C078493:HES1 protein, human