Sequence, phylogenetic and variant analyses of antithrombin III.
Antithrombin III (ATIII) performs a critical anticoagulant function by precluding the activation of blood clotting proteinases, aided by its two cofactors, heparin and heparan sulfate. Though several studies have been carried out on physiological, biochemical and structural perspectives on ATIII, so far there are limited studies on the molecular evolution of ATIII. Herein, we carried out molecular phylogenetic analyses of ATIII genes, combining gene structures, synteny and sequence-structural features for ATIII spanning 50 vertebrate genomes. ATIII is maintained over 450 MY on same genomic loci in vertebrates with few changes in ray-finned fishes and lost one intron 262c in tetrapods and coelacanth. In ray-finned fishes, ATIII gene has additional intron at the position 262c, which shared by group V1 members, corroborating that it is lost in other vertebrates and also in lobed-finned fish coelacanth (Latimeria chalumnae). We found that heparin binding basic residues, hD helix, three pairs of Cys-Cys salt bridges, N-glycosylation sites, serpin motifs and inhibitory reactive center loop (RCL) of ATIII protein are highly conserved. Using 1092 human genomes available from 1000G project, we also compiled 1997 ATIII variants, which reveals 76.2% single nucleotide polymorphisms (SNPs), 11.8% deletions and 8.1% insertions as three major classes of gene variations. These understandings may have medical importance as well.
['Kumar|Abhishek|A|', 'Bhandari|Anita|A|', 'Sarde|Sandeep J|SJ|', 'Goswami|Chandan|C|']
D000595:Amino Acid Sequence D000818:Animals D000990:Antithrombin III D001483:Base Sequence D017124:Conserved Sequence D005399:Fishes D006031:Glycosylation D006493:Heparin D006801:Humans D007438:Introns D008969:Molecular Sequence Data D016254:Mutagenesis, Insertional D010802:Phylogeny D017433:Protein Structure, Secondary D020539:Sequence Analysis, Protein D017384:Sequence Deletion
Antithrombin III Synteny ATIII variants Group V5 Phylogenetic analysis SerpinC1