Detection and characterization of Anticarsia gemmatalis ie-0 gene

BILEN MARCOS; AMOR SILVIA; MARIA JULIA OUSSET; PILLOFF MARCELA; LOZANO MARIO ENRIQUE; GHIRINGHELLI DANIEL

San Carlos de Bariloche

Congreso; SAIB XXXIX Reunión Nacional; 2003

During the early phase of infection of Autographa californica nuclear polyhedrosis virus, different immediate-early transcripts from the IE-0/IE-1 region are expressed which encode the IE-1 (nonspliced transcripts) and IE-0 (spliced transcripts) gene products. These two gene products differ only in that IE0 contains an additional stretch of 54 amino acids at the amino terminus. IE1 was expressed early and late, whereas IE0 was expressed only early in infection. The ie1 gene product stimulated the expression of the ie1 promoter-directed expression but down regulated expression from the ie0 promoter. The ie0 gene product also transactivated the ie1 promoter but did not affect the expression from its own promoter. In a previous work of our group, the ie-1 gene of Anticarsia gemmatalis nuclear polyhedrosis virus (AgMNPV) was cloned, sequenced and biochemically characterized. Examination of ie-1 gene leader region revealed sequences similar to published consensus splice acceptor site. In this study we show the presence of spliced transcripts in AgMNPV determining the splicing site between ie-0 and ie-1 sequences using 5’ RACE experiments. The same experiments allow us to determine the transcription initiation site for ie-0 transcripts. Furthermore, we detect the ie-0 coding sequences in a genomic library from AgMNPV. These clones were purified and sequenced.