RESUMEN
Baculoviruses encode a DNA-directed RNA polymerase that is evolutionarily divergent from cellular polymerases. This RNA polymerase is a multifunctional complex that has the ability to recognize late promoters, transcribe linked genes, and process transcripts at both the 5' and 3' ends. The LEF-4 subunit of the viral RNA polymerase is the mRNA capping enzyme, with both RNA triphosphatase and guanylyltransferase activities. Conversion to cap 1 structures is mediated by the viral enzyme MTase1 and another as yet unidentified methyltransferase. Termination is an intrinsic property of the viral RNA polymerase and occurs at oligoU rich sequences. Polyadenylation of the released transcripts is also a function of the viral RNA polymerase. Thus, although viral mRNAs resemble host messages with respect to their 5' and 3' end structures, the processing is mediated by viral enzymes and, in the case of the 3' ends, by mechanisms that differ from the host cell.
RESUMEN
Objective To obtain related genes of Cysticercus cellulosae from spliced leader (SL) cDNA library. Methods Spliced leader library of Cysticercus cellulosae was constructed using SL specific primer and oligo (dT)15 with M13M4 primer, and positive clones were then screened randomly, identified with enzyme restriction, followed by sequencing and homologous analysis. Results The amino acid sequence, encoded by the positive clone with a poly (A) 22 tail and a complete open reading frame (ORF), was with homology of RNA polymerase subunit genes of human, B. napus, fission yeast, A. thaliana, C. elegans and fruit fly up to 71.6%. Conclusion The protein, RNA polymerase subunit encoded putatively by the clone, is high conservative in different species.