Related Experiment Video
Updated: Nov 6, 2025

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
[Diseases Due to the Deficiency in Vitamin K Conversion System and Its Prevention]
1Laboratory of Hygienic Sciences, Kobe Pharmaceutical University.
Abstract:
Vitamin K is a fat-soluble vitamin that plays an important role in blood coagulation and bone formation. Vitamin K has homologues due to differences in the side chain structure, phylloquinone (abbreviated as vitamin K1, PK) having a phytyl side chain and menaquinones (MK-n, n=1 to 14) having an isoprenoid side chain structure. The main vitamin K that we take from our daily diet is PK, and a fermented food, natto, contains MK-7 produced by Bacillus subtilis natto. However, the majority of vitamin K present in the tissues of mammals, including humans, is menaquinone-4 (abbreviated as vitamin K2, MK-4) having a geranylgeranyl side chain. This reason is that PK or MK-n obtained in the diet is converted into MK-4 in the body. We identified that the UbiA prenyltransferase domain containing protein 1 (UBIAD1) is the conversion enzyme of PK and MK-n to MK-4. The physiological roles of MK-4 in all tissues of the whole body and the physiological significance of MK-4 converted from PK and MK-n by UBIAD1 have not been sufficiently elucidated yet. To investigate the function of UBIAD1 in vivo, we generated UBIAD1 systemic knockout mice and tissue-specific UBIAD1 knockout mice. In this paper, we introduce the usefulness of vitamin K for diseases that may involve vitamin K and UBIAD1.
More Related Videos
Related Concept Videos
Anticoagulant Drugs: Vitamin K Antagonists and Direct Oral Anticoagulants
Warfarin, a prominent vitamin K antagonist family member, exerts its effect by inhibiting the enzyme VKORC1 (vitamin K epoxide reductase complex 1). By hindering this enzyme, warfarin...
Vitamins
Disorders of Hemostasis
Thromboembolic Disorders
Two factors primarily cause thromboembolic conditions.
Anticoagulant Drugs: Low-Molecular-Weight Heparins
Venous Thrombosis III: Interprofessional Care
Role of Vitamins in Maintaining Bone Health
Vitamin A
Vitamin A is involved in the process of bone remodeling. Retinoic acid, the active metabolite of Vitamin A, has nuclear receptors in osteoblasts and osteoclasts, which are involved in bone remodeling.
Vitamin B12
Vitamin B12 acts as a cofactor during the formation of osteoblast-related proteins, such as osteocalcin. Vitamin B12 plays a role...

