Comparative genomic analysis of eutherian interferon genes

Abstract

The eutherian interferons were implicated as paradigmatic effector proteins in innate and acquired immunity. Yet, familiar interferon classification and nomenclature disagreed with functional genomics, phylogenetic and evolutionary analyses. Using eutherian comparative genomic analysis protocol and 35 public eutherian reference genomic sequence data sets, the present analysis attempted to resolve major disagreements in descriptions of eutherian interferons. Among 836 eutherian interferon potential coding sequences, the tests of reliability of eutherian public genomic sequences annotated, in aggregate, 495 complete coding sequences that were partitioned into supercluster IF1 and supercluster IF2 gene data sets. There were 29 human class 2 cytokine genes described, including initially described human IF1IC2 gene. There was convergence between nonhomologous eutherian supercluster IF1 and supercluster IF2 protein primary structures including common cysteine amino acid residues implicated in disulfide bonding. The integrated gene annotations, phylogenetic analysis and protein molecular analysis proposed revised and updated classification and nomenclature of eutherian interferons.