Related Experiment Video
Updated: Jul 18, 2026
07:51
Effect of Anti-c-fms Antibody on Osteoclast Formation and Proliferation of Osteoclast Precursor In Vitro
Published on: March 18, 2019
MafB negatively regulates RANKL-mediated osteoclast differentiation
Kabsun Kim1, Jung Ha Kim, Junwon Lee
1Research Institute of Medical Sciences and Medical Research Center for Gene Regulation, Chonnam National University Medical School, Hak-Dong 5, Dong-Ku, Gwangju 501-746, Korea.
Blood
|December 13, 2006
Summary
MafB negatively regulates osteoclast formation induced by RANKL. Overexpressing MafB inhibits osteoclast differentiation by interfering with key transcription factors, revealing its role in bone remodeling.
Area of Science:
- Cell Biology
- Molecular Biology
- Immunology
Background:
- Receptor activator of nuclear factor kappaB ligand (RANKL) is crucial for osteoclast differentiation from hematopoietic cells.
- Osteoclastogenesis involves complex regulation by various transcription factors.
Purpose of the Study:
- To investigate the role of MafB in RANKL-induced osteoclast differentiation.
- To elucidate the molecular mechanisms by which MafB modulates osteoclastogenesis.
Main Methods:
- Overexpression of MafB in bone marrow-derived monocyte/macrophage lineage cells (BMMs).
- RNA interference (RNAi) to reduce MafB expression.
- Analysis of osteoclast formation (TRAP+ multinuclear cells).
- Assessment of gene expression (NFATc1, OSCAR) and protein interactions.
Main Results:
- RANKL significantly reduces MafB expression during osteoclastogenesis.
- MafB overexpression inhibits osteoclast formation while preserving phagocytic activity.
- MafB attenuates the induction of NFATc1 and OSCAR.
- MafB interferes with the DNA-binding of c-Fos, Mitf, and NFATc1, inhibiting their transactivation.
- Reduced MafB expression enhances osteoclastogenesis and NFATc1/OSCAR expression.
Conclusions:
- MafB acts as a negative regulator of RANKL-induced osteoclast differentiation.
- MafB modulates osteoclastogenesis by interfering with key transcription factors like NFATc1 and OSCAR.
- MafB is an important modulator in RANKL-mediated bone remodeling processes.
Related Concept Videos
01:31Osteoclasts in Bone Remodeling
Osteoclasts are cells responsible for bone resorption and remodeling. They originate from hematopoietic progenitor cells present in the bone marrow. Numerous progenitor cells fuse to form multinucleated cells, each with 10-20 nuclei. A single osteoclast has a diameter of 150 to 200 µM. These cells have ruffled borders that break down the underlying bone tissue and release minerals such as calcium into the blood in bone resorption. Osteoclasts cling to bones with their ruffled edges during bone...
01:15Receptor Downregulation in MVBs
Multivesicular bodies (MVBs) are mature endosomes that sort ubiquitinated proteins and then fuse with lysosomes to degrade the sorted proteins. Epidermal growth factor (EGF) and its receptor (EGFR) form a complex that can be internalized through endocytosis, sorted into an MVB, and later degraded.
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR activation may...
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR activation may...
01:16TGF - β Signaling Pathway
The TGF-β signaling pathway regulates cell growth, differentiation, adhesion, motility, and development. TGF-β ligands that induce TGF-β signaling are synthesized in their latent form. Several proteases or cell surface receptors such as integrins act upon the latent form, releasing the active ligand. There are three types of mammalian TGF-βs: (TGF-β1, TGF-β2, and TGF-β3) that bind as homodimers or heterodimers to TGF-β receptors. The TGF-β receptors are of three kinds RI, RII, and RIII. The RI...
02:23Master Transcription Regulators
Master transcription regulators are regulatory proteins that are predominantly responsible for regulating the expression of multiple genes. Often these genes work in concert to drive a complex process. Activation of a master transcription regulator can lead to a cascade of transcriptional activation necessary for that outcome. These regulators can directly bind to the regulatory sequences of the various genes involved, or they can indirectly regulate transcription by binding to regulatory...
01:40Bone Remodeling
Bone remodeling is a continuous and balanced process of bone resorption by osteoclasts and bone formation by osteoblasts. In adults, it helps maintain bone mass and calcium homeostasis. While mechanical stress can stimulate turnover as part of the normal maintenance and reparative process, several hormones also regulate bone remodeling.