PUBLICATION

Developmental expression of vitamin k-dependent gamma-carboxylase activity in zebrafish embryos: effect of warfarin

Authors
Hanumanthaiah, R., Thankavel, B., Day, K., Gregory, M., and Jagadeeswaran, P.
ID
ZDB-PUB-020220-12
Date
2001
Source
Blood cells, molecules & diseases   27(6): 992-999 (Journal)
Registered Authors
Day, Kenneth, Gregory, Michael, Hanumanthaiah, Ravikumar, Jagadeeswaran, Pudur
Keywords
none
MeSH Terms
  • Amino Acid Sequence
  • Animals
  • Carbon-Carbon Ligases/antagonists & inhibitors
  • Carbon-Carbon Ligases/genetics
  • Carbon-Carbon Ligases/metabolism*
  • Embryo, Nonmammalian/drug effects
  • Embryo, Nonmammalian/embryology
  • Embryo, Nonmammalian/enzymology
  • Gene Expression Regulation, Developmental*/drug effects
  • Gene Expression Regulation, Developmental*/physiology
  • Microsomes/enzymology
  • Molecular Sequence Data
  • Ovum/enzymology
  • RNA, Messenger/analysis
  • Sequence Alignment
  • Warfarin/pharmacology
  • Zebrafish
PubMed
11831865 Full text @ Blood Cells Mol. Dis.
Abstract
Vitamin K-dependent gamma-carboxylation is an essential posttranslational modification required for the functional activity of coagulation proteins such as factors VII, IX, X, and prothrombin. Warfarin, an inhibitor of vitamin K-dependent gamma-carboxylation, was used in earlier work on adult zebrafish to provide evidence for the presence of vitamin K-dependent carboxylase in zebrafish. Here we demonstrate the presence of vitamin K-dependent carboxylase activity in zebrafish by directly assaying the microsomal fraction prepared from adult, unfertilized eggs, and embryos from different developmental stages. Gamma-carboxylase activity was detected both before and after fertilization of embryos and the activity levels remained relatively constant from 6 h postfertilization (hpf) through other advanced stages of development. The expression of activity in the early embryos (0--6 hpf) may be due to the presence of maternal protein since the activity was detected even in the unfertilized eggs. Gamma-carboxylase activity in the eggs as well as early embryos suggested that vitamin K-dependent carboxylase is important throughout development. The detection of vitamin K-dependent carboxylase mRNA by RT-PCR and inhibitor studies using warfarin confirmed these activity results. Further, these studies provide a basis for selecting warfarin-resistant zebrafish mutants in order to find genes regulating gamma-carboxylase activity including the yet unidentified vitamin K--epoxide reductase.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping