Characteristic genomic features of the fast-killing Epinotia aporema granulovirus

FERRELLI MARÍA LETICIA; SALVADOR RICARDO; BERRETTA MARCELO F.; GHIRINGHELLI PABLO DANIEL ; SCIOCCO-CAP ALICIA

Trabzon

Congreso; 43th Annual Meeting of the Society for Invertebrate Pathology. 10th International Colloquium on Invertebrate Pathology and Microbial Control. The Final Meeting of COST862: Bacterial Toxins for Insect Control; 2010

Society for Invertebrate Pathology

Epinotia aporema (Lep. Tortricidae) is a major pest of legume crops in South America. A granulovirus isolated from E. aporema larvae (EpapGV) has demonstrated its properties as a fast-killing, type II granulovirus in our previous studies. In order to further characterize this virus, a draft sequence of its complete genome was obtained and its gene content analyzed preliminarily. The sequences were assembled in a 119.090 bp-long contig. The first analysis yielded a putative list of 141 ORFs that met the criterion of having a minimum of 50 codons and minimal overlap. They were compared with the GenBank sequences. The initial analysis focused on distinctive genomic characteristics compared to 12 granuloviruses sequenced so far. Blast searches revealed the presence of 31 baculovirus core genes as well as the GV-specific set. Additionally, some characteristic features include the presence of chitinase, cathepsin, gp37, dUTPase and ribonucleotide reductase subunits and the absence of enhancin. EpapGV genome sequence also revealed the presence of a new putative gene in the family Baculoviridae. This ORF encodes a 224 amino acid-long protein for which BlastP search resulted in multiple hits with tymidylate kinase-like proteins of several organisms. The nucleotide flanking sequences of this putative gene were analyzed. It appears to have an early promoter and a polyadenylation signal. This enzyme is involved in the dTTP biosynthesis and interestingly it is in the same biosythetic pathway to which ribonucleotide reductase and dUTPase belong, two genes present in some other baculoviruses.