TY - JOUR
T1 - Stabilization of warfarin-binding pocket of VKORC1 and VKORL1 by a peripheral region determines their different sensitivity to warfarin inhibition
AU - Shen, G.
AU - Li, S.
AU - Cui, W.
AU - Liu, S.
AU - Liu, Q.
AU - Yang, Y.
AU - Gross, M.
AU - Li, W.
N1 - Publisher Copyright:
© 2018 International Society on Thrombosis and Haemostasis
PY - 2018/6
Y1 - 2018/6
N2 - Essentials VKORL1 and VKORC1 have a similar overall structure and warfarin-binding pocket. A peripheral region stabilizing this pocket controls warfarin sensitivity of the VKOR paralogs. A human single nucleotide polymorphism in this region renders VKORL1 sensitive to warfarin. A group of warfarin-resistant mutations in VKORC1 acts by disrupting peripheral interactions. Summary: Background The human genome encodes two paralogs of vitamin-K-epoxide reductase, VKORC1 and VKORL1, that support blood coagulation and other vitamin-K-dependent processes. Warfarin inhibits both enzymes, but VKORL1 is relatively resistant to warfarin. Objectives To understand the difference between VKORL1 and VKORC1, and the cause of warfarin-resistant (WR) mutations in VKORC1. Methods We performed systematic mutagenesis and analyzed warfarin responses with a cell-based activity assay. Mass spectrometry analyses were used to detect cellular redox state. Results VKORC1 and VKORL1 adopt a similar intracellular redox state with four-transmembrane-helix topology. Most WR mutations identified in VKORC1 also confer resistance in VKORL1, indicating that warfarin inhibits these paralogs at a common binding site. A group of WR mutations, distant from the warfarin-binding site, show significantly less resistance in VKORL1 than in VKORC1, implying that their different warfarin responses are determined by peripheral interactions. Remarkably, we identify a critical peripheral region in which single mutations, Glu37Lys or His46Tyr, drastically increase the warfarin sensitivity of VKORL1. In the background of these warfarin-sensitive VKORL1 mutants, WR mutations showing relative less resistance in wild-type VKORL1 become much more resistant, suggesting a structural conversion to resemble VKORC1. At this peripheral region, we also identified a human single nucleotide polymorphism that confers warfarin sensitivity of VKORL1. Conclusions Peripheral regions of VKORC1 and VKORL1 primarily maintain the stability of their common warfarin-binding pocket, and differences of such interactions determine their relative sensitivity to warfarin inhibition. This new model also explains most WR mutations located at the peripheral regions of VKORC1.
AB - Essentials VKORL1 and VKORC1 have a similar overall structure and warfarin-binding pocket. A peripheral region stabilizing this pocket controls warfarin sensitivity of the VKOR paralogs. A human single nucleotide polymorphism in this region renders VKORL1 sensitive to warfarin. A group of warfarin-resistant mutations in VKORC1 acts by disrupting peripheral interactions. Summary: Background The human genome encodes two paralogs of vitamin-K-epoxide reductase, VKORC1 and VKORL1, that support blood coagulation and other vitamin-K-dependent processes. Warfarin inhibits both enzymes, but VKORL1 is relatively resistant to warfarin. Objectives To understand the difference between VKORL1 and VKORC1, and the cause of warfarin-resistant (WR) mutations in VKORC1. Methods We performed systematic mutagenesis and analyzed warfarin responses with a cell-based activity assay. Mass spectrometry analyses were used to detect cellular redox state. Results VKORC1 and VKORL1 adopt a similar intracellular redox state with four-transmembrane-helix topology. Most WR mutations identified in VKORC1 also confer resistance in VKORL1, indicating that warfarin inhibits these paralogs at a common binding site. A group of WR mutations, distant from the warfarin-binding site, show significantly less resistance in VKORL1 than in VKORC1, implying that their different warfarin responses are determined by peripheral interactions. Remarkably, we identify a critical peripheral region in which single mutations, Glu37Lys or His46Tyr, drastically increase the warfarin sensitivity of VKORL1. In the background of these warfarin-sensitive VKORL1 mutants, WR mutations showing relative less resistance in wild-type VKORL1 become much more resistant, suggesting a structural conversion to resemble VKORC1. At this peripheral region, we also identified a human single nucleotide polymorphism that confers warfarin sensitivity of VKORL1. Conclusions Peripheral regions of VKORC1 and VKORL1 primarily maintain the stability of their common warfarin-binding pocket, and differences of such interactions determine their relative sensitivity to warfarin inhibition. This new model also explains most WR mutations located at the peripheral regions of VKORC1.
KW - blood coagulation
KW - drug resistance
KW - vitamin K
KW - vitamin K epoxide reductases
KW - warfarin
UR - http://www.scopus.com/inward/record.url?scp=85047790898&partnerID=8YFLogxK
U2 - 10.1111/jth.14127
DO - 10.1111/jth.14127
M3 - Article
C2 - 29665197
AN - SCOPUS:85047790898
SN - 1538-7933
VL - 16
SP - 1164
EP - 1175
JO - Journal of Thrombosis and Haemostasis
JF - Journal of Thrombosis and Haemostasis
IS - 6
ER -