1. Expansion and molecular evolution of the interferon-induced 2'-5' oligoadenylate synthetase gene family
- Author
-
Chandra Mitnik, Graziela Valente, Sudhir Kumar, and Georgia Floyd-Smith
- Subjects
Molecular Sequence Data ,Evolution, Molecular ,Endonuclease ,Molecular evolution ,Phylogenetics ,Gene Duplication ,Gene duplication ,Genetics ,2',5'-Oligoadenylate Synthetase ,Gene family ,Animals ,Humans ,Amino Acid Sequence ,Molecular Biology ,Gene ,Ecology, Evolution, Behavior and Systematics ,Phylogeny ,Chromosomes, Human, Pair 12 ,biology ,Base Sequence ,Sequence Homology, Amino Acid ,2'-5'-Oligoadenylate ,Chromosome Mapping ,Porifera ,Viral replication ,Multigene Family ,Vertebrates ,biology.protein ,Interferons ,Sequence Alignment - Abstract
The mammalian 2'-5' oligoadenylate synthetases (2'-5'OASs) are enzymes that are crucial in the interferon-induced antiviral response. They catalyze the polymerization of ATP into 2'-5'-linked oligoadenylates which activate a constitutively expressed latent endonuclease, RNaseL, to block viral replication at the level of mRNA degradation. A molecular evolutionary analysis of available OAS sequences suggests that the vertebrate genes are members of a multigene family with its roots in the early history of tetrapods. The modern mammalian 2'-5'OAS genes underwent successive gene duplication events resulting in three size classes of enzymes, containing one, two, or three homologous domains. Expansion of the OAS gene family occurred by whole-gene duplications to increase gene content and by domain couplings to produce the multidomain genes. Evolutionary analyses show that the 2'-5'OAS genes in rodents underwent gene duplications as recently as 11 MYA and predict the existence of additional undiscovered OAS genes in mammals.
- Published
- 2000