Nucleotide sequence of the gene coding for human factor VII, a vitamin K-dependent protein participating in blood coagulation.

Abstract

Activated factor VII (factor VIIa) is a vitamin K-dependent plasma serine protease that participates in a cascade of reactions leading to the coagulation of blood. Two overlapping genomic clones containing sequences encoding human factor VII were isolated and characterized. The complete sequence of the gene was determined and found to span about 12.8 kilobases. The mRNA for factor VII as demonstrated by cDNA cloning is polyadenylylated at multiple sites but contains only one AAUAAA poly(A) signal sequence. The mRNA can undergo alternative splicing, forming one transcript containing eight segments as exons and another with an additional exon that encodes a larger prepro leader sequence. The latter transcript has no known counterpart in the other vitamin K-dependent proteins. The positions of the introns with respect to the amino acid sequence encoded by the eight essential exons of factor VII are the same as those present in factor IX, factor X, protein C, and the first three exons of prothrombin. These exons code for domains generally conserved among members of this gene family. The comparable introns in these genes, however, are dissimilar with respect to size and sequence, with the exception of intron C in factor VII and protein C. The gene for factor VII also contains five regions made up of tandem repeats of oligonucleotide monomer elements. More than a quarter of the intron sequences and more than a third of the 3' untranslated portion of the mRNA transcript consist of these minisatellite tandem repeats.Factor VII is a vitamin K-dependent glycoprotein, synthesized in the liver and secreted into the blood as a single-chain zymogen. It participates in the extrinsic pathway of blood coagulation in an activated form called factor VIla (1). Conversion of factor VII to factor VIa by either factor Xa, factor XIIa, factor IXa, or thrombin involves the cleavage of a single peptide bond in the zymogen, resulting in the formation of a serine protease containing a light and heavy chain held together by a disulfide bond (2). The light chain, originating from the amino-terminal region of factor VII, contains 10 y-carboxyglutamic acid residues (3). These amino acids, which require vitamin K for their biosynthesis, bind calcium ions and are involved in the interaction of factor VII with phospholipid vesicles. The heavy chain, originating from the carboxyl-terminal region of the protein, contains the serine protease or catalytic portion of the molecule. Factor VIIa, in the presence of tissue factor and calcium ions, then converts factor X to factor Xa and/or factor IX to factor IXa (4).Recently Hagen et al. (5) isolated and characterized cDNA clones coding for factor VII. The largest cDNA coded for a mature protein of 406 amino acids. The cDNA sequence and amino acid sequence data indicated that conversion of factor VII to factor VIa involves cleavage of an internal arginineisoleucine bond forming a light chain of 152 amino acids and a heavy chain of 254 amino acids. Two different cDNA clones predicted alternative s...

Daily and Circadian Rhythms of Tissue Factor Pathway Inhibitor and Factor VII Activity

“…FVII exhibited true circadian rhythms, further supported by the presence in mouse 29 (Ϫ483, Ϫ1054) and human 30 (Ϫ140) FVII 5Ј flanking regions of E-box sequences, hallmarks of putative regulation by clock proteins. 31 Our data suggest that the chronobiological features of these coagulation factors, and particularly their variation patterns, have to be taken into account in the analysis of FVII and TFPI plasma levels.…”

Analysis of the genotypes and phenotypes of 37 unrelated patients with inherited factor VII deficiency

“…DGGE could not be applied to the entire coding sequence because the base composition of FVII gene is GC rich with a 60% G+C content. 7 This characteristic is common to other vitamin K dependent factors such as factor X or Protein C. 7 This explains why gradients with high percentages of denaturant as well as long running times were necessary to accurately identify FVII mutations using DGGE. However, DGGE screening allowed the detection of 46 out of the 68 FVII mutated alleles (68%), corresponding to the complete genotypes of one third of the patients (13/37).…”

“…The coding portions, intron/exon boundaries and the 5' flanking region (5'FR) of the FVII gene were amplified from genomic DNA by polymerase chain reaction (PCR). Primer sets were designed according to the published FVII gene sequence 7 and are listed in Table 2.…”

Site‐directed mutagenesis but not γ‐carboxylation of Glu‐35 in factor VIIa affects the association with tissue factor

“…The N-terminal domain, encoded on a separate exon, contains the first 37 amino acid residues including all 10 y-carboxyglutamic acid (Gla) residues [2]. This so-called Gla domain binds seven Ca r+ ions [3,4], an event mediated by the Gla residues, and thereby attains a membrane-interactive ability through the exposure of hydrophobic side chains [4,5].…”