ARS | Publication request: No evidence for translation of pog, a predicted overlapping gene of Solenopsis invicta virus 1

Submitted to: Virus Genes
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 31, 2012
Publication Date: April 13, 2012
Citation: Valles, S.M., Sabath, N. 2012. No evidence for translation of pog, a predicted overlapping gene of Solenopsis invicta virus 1. Virus Genes. 45:84-89.

Interpretive Summary: The red imported fire ant is an invasive insect pest that currently infests about 300 million acres and causes economic losses that exceed 6 billion dollars annually in the United States. Solenopsis invicta virus 1 is the first virus discovered from the red imported fire ant. This virus may find utility as a biopesticide to naturally control this ant. Understanding the infection process of SINV-1 is important in development as a biopesticide. In an effort to advance our understanding of the infection process of SINV-1, scientists at the USDA-ARS, Center for Medical, Agricultural and Veterinary Entomology (Gainesville, FL) and the Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Switzerland have examined SINV-1-infected fire ant colonies for the presence of a gene product that may be uniquely expressed in SINV-1. These results advance our knowledge of the virus infection process and the evolution of these viruses.

Technical Abstract: An overlapping open reading frame (ORF) with a potential to encode a functional protein has been identified within the 3'-proximal ORF of Solenopsis invicta virus 1 (SINV-1) and three bee viruses. This ORF has been referred to as predicted overlapping gene (pog). Protein motif searches of pog revealed weak relationships precluding assignment of a potential function. Neither a transcript nor protein encoded by the pog ORF has been detected. However, recently, a protein encoded by the corresponding +1 overlapping open reading frame (termed ORFx) in the Israeli acute paralysis virus (IAPV) was demonstrated by recombinant means as well as in IAPV-infected honey bees. The objective of our study was to attempt to provide empirical evidence for the presence of a pog protein from SINV-1-infected fire ants. A number of different laboratory and field SINV-1-infected Solenopsis invicta preparations were examined by Western blotting for the presence of a pog protein sequence. In every case, these preparations failed to yield any detectable bands when probed with a polyclonal antibody preparation raised to a portion of the pog predicted protein sequence. Although impossible to prove a negative result, proper controls used in these studies suggested that the pog ORF is not translated into a functional protein in SINV-1.