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has been cited by the following article:

• TITLE: Prohibitins, novel vitamin K2 target factors in osteoblast

  AUTHORS: Tatsuya Uebi, Makoto Umeda, Naoya Maekawa, Satoshi Karasawa, Hiroshi Handa, Takeshi Imai

  KEYWORDS: Vitamin K2; Prohibitin; Osteoblast; Runt-Related Transcription Factor 2 (Runx2)

  JOURNAL NAME: Journal of Biosciences and Medicines, Vol.1 No.3, December 12, 2013

  ABSTRACT: Vitamin K2 (VK2, menaquinone) is a drug for osteoporosis. VK2 acts as a cofactor for γ-glutamyl carboxylase, which catalyzes the carboxylation of specific glutamic acid residues (γ-carboxylation) of substrate proteins. Here we demonstrate that VK2 also regulate osteoblastgenic marker gene expression. Using VK2-immobilzed nanobeads new target proteins were purified and identified from osteoblastic cell line. They are prohibitin 1 and 2 (PHB1 & 2), respectively. To confirm the PHBs function on VK2-dependent transcription, PHB1 & 2 were knock-down and osteocalcin gene 2 transcriptions were analyzed, indicating that PHBs regulate VK2-dependent transcription. Taken together PHBs are VK2 target proteins for osteoblastgenic transcription.