Comparative Analyses of the Anticarsia gemmatalis Multicapsid Nuclear Polyhedrosis Virus (AgMNPV) GP64 Glicoprotein with functional homologues of the family Baculoviridae

PILLOFF MARCELA; BILEN MARCOS; LOZANO MARIO ENRIQUE; GHIRINGHELLI DANIEL

Villa Carlos Paz

Congreso; XXXVIII Reunión Anual de SAIB; 2002

Baculoviridae are the main viruses infecting lepidoptera. Their genome consists of a circular dsDNA molecule ranging in size from ~80 to 180 kbp. The progeny generation is biphasic, yielding budded virus (BV) in early stages and occluded derived virus (ODV) in the late stages of infection. The morphology and intracellular location of the occlusion bodies determines the classification of this family into two genera: Nucleopolyhedrovirus (NPV) and Granulovirus. The NPVs can be further subdivided into groups I and II based on phylogenetic studies of many genes. The BV envelopes of group I NPVs, contains an abundant viral-encoded glycoprotein designated GP64; whereas the GV and group II NPV envelopes have glycoproteins (ORF31 in CpGV and ORF130 in LdMNPV) that are functional homologues. These proteins are responsibles for the viral entry in the cell through an endocytic pathway and they are not found in the ODV envelopes. In this work, we show the identification, cloning and sequencing of the AgMNPV gp64 locus. The plasmid clones were functionally tested to assess the presence of a fusogenic activity similar to that expected for the GP64 protein. In addition, the complete sequence of the gp64 ORF (1500 nt. long) and coded product (499 amino acids long) were comparatively analyzed with the corresponding sequences of other baculoviruses using bioinformatic tools. The phylogenetic analysis confirms that AgMNPV is a member of group I NPVs