Serum Deprivation-Induced Human GM3 Synthase (hST3Gal V) Gene Expression Is Mediated by Runx2 in Human Osteoblastic MG-63 Cells

International Journal of Molecular Sciences

Hyun-Kyoung Yoon²  Ji-Won Lee²  Kyoung-Sook Kim²  Seo-Won Mun²  Dong-Hyun Kim²  Hyun-Jun Kim³  Cheorl-Ho Kim¹  Young-Choon Lee² 

[1] Molecular and Cellular Glycobiology Unit, Department of Biological Sciences, SungKyunKwan University, Kyunggi-Do 440-746, Korea;Department of Medicinal Biotechnology, College of Health Sciences, Dong-A University, Busan 604-714, Korea;Department of Orthopaedic Surgery, College of Medicine, Dong-A University, Busan 604-714, Korea;

关键词: serum deprivation;    human GM3 synthase (hST3Gal V);    MG-63 cells;    runt-related transcription factor 2 (Runx2);    transcriptional regulation;   

DOI  :  10.3390/ijms17010035

来源: mdpi

【 摘 要 】

Serum deprivation (SD) is well known to induce G0/G1 cell cycle arrest and apoptosis in various cells. In the present study, we firstly found that SD could induce G1 arrest and the differentiation of human osteoblastic MG-63 cells, as evidenced by the increase of osteoblastic differentiation markers, such as bone morphogenetic protein-2 (BMP-2), osteocalcin and runt-related transcription factor 2 (Runx2). In parallel, gene expression of human GM3 synthase (hST3Gal V) catalyzing ganglioside GM3 biosynthesis was upregulated by SD in MG-63 cells. The 5′-flanking region of the hST3Gal V gene was functionally characterized to elucidate transcriptional regulation of hST3Gal V in SD-induced MG-63 cells. Promoter analysis using 5′-deletion constructs of the hST3Gal V gene demonstrated that the −432 to −177 region functions as the SD-inducible promoter. Site-directed mutagenesis revealed that the Runx2 binding sites located side-by-side at positions −232 and −222 are essential for the SD-induced expression of hST3Gal V in MG-63 cells. In addition, the chromatin immunoprecipitation assay also showed that Runx2 specifically binds to the hST3Gal V promoter region containing Runx2 binding sites. These results suggest that SD triggers upregulation of hST3Gal V gene expression through Runx2 activation by BMP signaling in MG-63 cells.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.