RRC ID 39062
Author Shirakawa J, Harada H, Noda M, Ezura Y.
Title PTH-Induced Osteoblast Proliferation Requires Upregulation of the Ubiquitin-Specific Peptidase 2 (Usp2) Expression.
Journal Calcif Tissue Int
Abstract Osteoporosis is a common disease that increases individual's fragility fracture risk. PTH is the only therapeutic agent for severe osteoporosis that requires anabolic action of bone formation. Although a part of the PTH actions is explained by increased proliferation of osteoblastic precursor cells, the mechanisms involved in the proliferation of osteoblastic cells by PTH have not been clarified yet. Therefore, in this study, we investigated the effects of PTH on gene expression in the cultured osteoblastic MC3T3-E1 cells, and found that the ubiquitin-specific peptidase 2 (Usp2) may be one of the direct target genes of PTHR signaling. Usp2 is a deubiquitination enzyme targeting various factors including CyclinD1 in cancer cells and PTH receptor 1 in osteoblasts. We confirmed that consistent induction of Usp2 expression peaked at 1 h by PTH1-34 (teriparatide) in MC3T3-E1 cells and primary calvarial osteoblasts. Among the three known splicing variants of the Usp2, we found the isoforms 1 and 2 are predominantly expressed in osteoblasts. Live-imaging analysis of the Fucci-transgenic mouse-derived primary osteoblasts indeed demonstrated that Usp2 is required for the PTH1-34-induced osteoblast proliferation. Western blotting analysis of the CyclinD1 indicated that Usp2 knock-down influences the paradoxical changes of CyclinD1 protein levels in this condition. Our data indicate that Usp2 is required for the PTH1-34-induced proliferation of osteoblasts.
Volume 98(3)
Pages 306-15
Published 2016-3-1
DOI 10.1007/s00223-015-0083-5
PII 10.1007/s00223-015-0083-5
PMID 26643174
MeSH 3T3 Cells Alternative Splicing Animals Bone and Bones / metabolism Cell Proliferation Cyclin D1 / metabolism Gene Expression Regulation Mice Mice, Transgenic Osteoblasts / cytology* Parathyroid Hormone / metabolism* RNA, Small Interfering / metabolism Signal Transduction Ubiquitin-Specific Proteases / metabolism* Up-Regulation
IF 3.265
Times Cited 6
Human and Animal Cells MC3T3-E1(RCB1126)