Related Experiment Video
Updated: Apr 16, 2026

Detection of Signaling Effector-Complexes Downstream of BMP4 Using in situ PLA, a Proximity Ligation Assay
Published on: March 3, 2011
Arkadia enhances BMP signalling through ubiquitylation and degradation of Smad6
Yutaro Tsubakihara1, Atsuhiko Hikita2, Shin Yamamoto3
1Department of Molecular Medicine for Pathogenesis, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime; Division of Bio-imaging, Proteo-Science Center, Ehime University, Shitsukawa, Toon, Ehime; Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo; Department of Gastroenterology and Metabiology, Ehime University, Shitsukawa, Toon, Ehime; Translational Research Center, Ehime University Hospital, Shitsukawa, Toon, Ehime; and Department of Biochemistry, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Yamanashi, Japan.
Abstract:
Arkadia, a positive regulator of Smad-dependent signalling via the transforming growth factor-β (TGF-β) family, is an E3 ubiquitin ligase that induces ubiquitylation and proteasome-dependent degradation of TGF-β suppressors such as Smad7, c-Ski and SnoN. In this study, we examined the effects of Arkadia on bone morphogenetic protein (BMP)-induced osteoblast differentiation. Knockdown of Arkadia reduced mineralization and expression of osteoblast differentiation markers. Furthermore, we showed that Smad6, a BMP-specific inhibitory Smad, is a target of Arkadia: wild-type (WT) Arkadia, but not the C937A (CA) mutant lacking E3 ubiquitin-ligase activity, induced ubiquitylation and proteasome-dependent degradation of Smad6. Accordingly, protein levels of Smad6, Smad7 and c-Ski were elevated in MEFs from Arkadia KO mice. Finally, expression of Arkadia attenuated blockade of BMP signalling by Smad6 in a transcriptional reporter assay. These results demonstrate that Smad6 is a novel target of Arkadia, and that Arkadia positively regulates BMP signalling via degradation of Smad6, Smad7 and c-Ski/SnoN.
More Related Videos
11:38Visualization and Quantification of TGFβ/BMP/SMAD Signaling under Different Fluid Shear Stress Conditions using Proximity-Ligation-Assay
Published on: September 14, 2021
07:15Mechanism of Kemeng Fang's Inhibition of Podocyte Apoptosis in Rats with Membranous Nephropathy through the PI3K/AKT Signaling Pathway
Published on: August 23, 2024
Related Concept Videos
TGF - β Signaling Pathway
The JAK-STAT Signaling Pathway
PI3K/mTOR/AKT Signaling Pathway
Regulated Protein Degradation
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
Regulated Protein Degradation
Receptor Downregulation in MVBs
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR...