机构:[a]The Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou 215000, China[b]Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases and Institute of Neuroscience, Soochow University, Suzhou, Jiangsu 215021, China[c]The Center of Diagnosis and Treatment for Children’s Bone Diseases, The Children’s Hospital Affiliated to Soochow University, Suzhou, Jiangsu 215000, China
Low-dose irradiation (LDI) induces osteoblast differentiation, however the underlying mechanisms are not fully understood. In this study, we explored the potential role of DNA-dependent protein kinase catalytic subunit (DNA-PKcs)-Akt signaling in LDI-induced osteoblast differentiation. We confirmed that LDI promoted mouse calvarial osteoblast differentiation, which was detected by increased alkaline phosphatase (ALP) activity as well as mRNA expression of type I collagen (Col 1) and runt-related transcription factor 2 (Runx2). In mouse osteoblasts, LDI (1 Gy) induced phosphorylation of DNA-PKcs and Akt (mainly at Ser-473). The kinase inhibitors against DNA-PKcs (NU-7026 and NU-7441) or Akt (LY294002, perifosine and MK-2206), as well as partial depletion of DNA-PKcs or Akt1 by targeted-shRNA, dramatically inhibited LDI-induced Akt activation and mouse osteoblast differentiation. Further, siRNA-knockdown of SIN1, a key component of mTOR complex 2 (mTORC2), also inhibited LDI-induced Akt Ser-473 phosphorylation as well as ALP activity increase and Col I/Runx2 expression in mouse osteoblasts. Co-immunoprecipitation (Co-IP) assay results demonstrated that LDI-induced DNA-PKcs-SIN1 complexation, which was inhibited by NU-7441 or SIN1 siRNA-knockdown in mouse osteoblasts. In summary, our data suggest that DNA-PKcs-SIN1 complexation-mediated Akt activation (Ser-473 phosphorylation) is required for mouse osteoblast differentiation. (C) 2014 Elsevier Inc. All rights reserved.
基金:
The study was supported by the Nature Science Foundation of
China (30872637, 81171712), and by Jiangsu Provincial Special
Program of Clinical Medical Science (BL2014040).
第一作者机构:[a]The Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou 215000, China
共同第一作者:
通讯作者:
通讯机构:[c]The Center of Diagnosis and Treatment for Children’s Bone Diseases, The Children’s Hospital Affiliated to Soochow University, Suzhou, Jiangsu 215000, China[*]The Department of Orthopedics, The Second Affiliated Hospital of Soochow University, San-xiang Road, Suzhou 215000, China.
推荐引用方式(GB/T 7714):
Yong Xu,Shi-ji Fang,Li-juan Zhu,et al.DNA-PKcs-SIN1 complexation mediates low-dose X-ray irradiation (LDI)-induced Akt activation and osteoblast differentiation[J].BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS.2014,453(3):362-7.doi:10.1016/j.bbrc.2014.09.088.
APA:
Yong Xu,Shi-ji Fang,Li-juan Zhu,Lun-qing Zhu&Xiao-zhong Zhou.(2014).DNA-PKcs-SIN1 complexation mediates low-dose X-ray irradiation (LDI)-induced Akt activation and osteoblast differentiation.BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS,453,(3)
MLA:
Yong Xu,et al."DNA-PKcs-SIN1 complexation mediates low-dose X-ray irradiation (LDI)-induced Akt activation and osteoblast differentiation".BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS 453..3(2014):362-7