Expansion of poxvirus RNA polymerase subunits sharing homology with corresponding subunits of RNA polymerase II

• Published in: Virus genes 2008-04, Vol.36 (2), p.307-311
• Main Authors: Knutson, Bruce A., Broyles, Steven S.
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Biomedical and Life Sciences; Biomedicine; Databases, Protein; DNA-directed RNA polymerase; DNA-Directed RNA Polymerases - chemistry; DNA-Directed RNA Polymerases - genetics; Evolution, Molecular; Genes, Viral; Homology; Humans; Medical Microbiology; Methanobacterium - enzymology; Methanobacterium - genetics; Methanococcus - enzymology; Methanococcus - genetics; Molecular Sequence Data; Nucleotide sequence; Plant Sciences; Poxvirus; Protein structure; Protein Structure, Secondary; RNA Polymerase II - chemistry; RNA Polymerase II - genetics; Secondary structure; Sequence Alignment; Vaccinia; Vaccinia virus - enzymology; Vaccinia virus - genetics; Virology; Yeasts - enzymology; Yeasts - genetics
• ISSN: 0920-8569; 1572-994X
• DOI: 10.1007/s11262-008-0207-3

Poxvirus-encoded RNA polymerases were known previously to share extensive sequence homology in their two largest subunits with the corresponding subunits of cellular RNA polymerases and a modest alignment between the smallest poxvirus subunit and RBP10 of RNA polymerase II. The remaining subunits had no apparent cellular homologs. In this study, the HHpred program that combines amino acid sequence alignments with secondary structure predictions was used to search for homologs to the poxvirus RNA polymerase subunits. Significant matches of vaccinia RNA polymerase 22-, 19-, and 18-kDa subunits to RNA polymerase II subunits RPB5, 6, and 7, respectively, were identified. These results strengthen the concept that poxviral RNA polymerases likely evolved from cellular RNA polymerases.