Systematic CpT (ApG) Depletion and CpG Excess Are Unique Genomic Signatures of Large DNA Viruses Infecting Invertebrates

作者：Upadhyay Mohita; Sharma Neha; Vivekanandan Perumal^*

来源：PLos One, 2014, 9(11): e111793.

DOI：10.1371/journal.pone.0111793

Differences in the relative abundance of dinucleotides, if any may provide important clues on host-driven evolution of viruses. We studied dinucleotide frequencies of large DNA viruses infecting vertebrates (n = 105; viruses infecting mammals = 99; viruses infecting aves = 6; viruses infecting reptiles = 1) and invertebrates (n = 88; viruses infecting insects = 84; viruses infecting crustaceans = 4). We have identified systematic depletion of CpT(ApG) dinucleotides and over-representation of CpG dinucleotides as the unique genomic signature of large DNA viruses infecting invertebrates. Detailed investigation of this unique genomic signature suggests the existence of invertebrate host-induced pressures specifically targeting CpT(ApG) and CpG dinucleotides. The depletion of CpT dinucleotides among large DNA viruses infecting invertebrates is at least in part, explained by non-canonical DNA methylation by the infected host. Our findings highlight the role of invertebrate host-related factors in shaping virus evolution and they also provide the necessary framework for future studies on evolution, epigenetics and molecular biology of viruses infecting this group of hosts.

• 出版日期2014-11-4