Affiliation:
1. USC 1233 RS2GP, VetAgro Sup, INRAE, University of Lyon, 69280, Marcy L’Etoile, France.
Abstract
Vitamin K epoxide reductase (VKOR) activity is catalyzed by the VKORC1 enzyme. It is a target of vitamin K antagonists (VKA). Numerous mutations of VKORC1 have been reported and are suspected to confer resistance to VKA and (or) affect its velocity. Nevertheless, the results of these studies have been conflicting, and the functional characterization of these mutations in the cell system is complex because of the interweaving of VKOR activity in the vitamin K cycle. In this study, a new cellular approach was implemented to evaluate the vitamin K cycle in HEK293 cells. This global approach was based on the vitamin K quinone/vitamin K epoxide (K/KO) balance. In the presence of VKA or when VKORC1 and VKORC1L1 were knocked out, the K/KO balance decreased significantly due to the accumulation of vitamin KO. In contrast, when VKORC1 was overexpressed, the balance remained unchanged, demonstrating the limitation of VKOR activity. This limitation was shown to be due to insufficient expression of the activation partner of VKORC1, as overexpression of protein disulfide isomerase (PDI) overcomes this limitation. This study is the first to demonstrate the functional interaction between VKORC1 and PDI.
Publisher
Canadian Science Publishing
Subject
Cell Biology,Molecular Biology,Biochemistry
Cited by
4 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献