Why is CpG suppressed in the genomes of virtually all small eukaryotic viruses but not in those of large eukaryotic viruses?
AUTOR(ES)
Karlin, S
RESUMO
Dinucleotide over- and underrepresentation is evaluated in all available completely sequenced DNA or RNA viral genomes, ranging in size from 3 to 250 kb (available RNA viruses fall into the small-virus category). The dinucleotide CpG is statistically underrepresented (suppressed) in all but four of the small viruses (more than 75 with lengths of < 30 kb) but has normal relative abundances in most large viruses (> or = 30 kb). Most retrotransposons in eukaryotic species also show low CpG relative abundances. Interpretations, especially in some cases of DNA viruses or viruses with a DNA intermediate, might relate to methylation effects and modes of viral integration and excision. Other possible contributing factors relate to dinucleotide stacking energies, special mutation mechanisms, and evolutionary events.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=236777Documentos Relacionados
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