Identification and expression of two baculovirus gp37 genes.

Area of Science:

• Molecular biology
• Virology
• Genetics

Background:

• Baculoviruses are insect pathogens with complex genomes.
• The function of many baculovirus genes, including gp37, remains poorly understood.
• Comparative genomics aids in understanding viral evolution and gene function.

Purpose of the Study:

• To identify and characterize the gp37 genes in Mamestra brassicae multicapsid nucleopolyhedrovirus (MbMNPV) and Lymantria dispar multicapsid nucleopolyhedrovirus (LdMNPV).
• To investigate the evolutionary relationship of baculovirus gp37 genes with other viral and bacterial genes.
• To determine the transcriptional regulation and post-translational modification of MbMNPV and LdMNPV gp37 proteins.

Main Methods:

• Gene identification and sequence analysis.
• Phylogenetic analysis using established computational methods.
• Transcriptional analysis using Northern blotting or RT-PCR.
• Protein localization studies using confocal immunofluorescence microscopy.
• Post-translational modification analysis using tunicamycin treatment.

Main Results:

• The gp37 genes from MbMNPV and LdMNPV were identified and found to be similar to other baculovirus gp37 and entomopoxvirus fusolin genes.
• Phylogenetic analysis revealed distinct clades for baculovirus gp37 and entomopoxvirus fusolin genes, with no evidence of recent horizontal gene transfer.
• MbMNPV and LdMNPV gp37 genes are transcribed from late baculovirus promoters, with MbMNPV gp37 also showing putative early transcription.
• MbMNPV GP37 is N-glycosylated and localized to the cytoplasm, likely within the endoplasmic reticulum.

Conclusions:

• The study provides a comprehensive characterization of baculovirus gp37 genes, clarifying their evolutionary distinctness from entomopoxvirus fusolin genes.
• The findings suggest that baculovirus gp37 genes have ancient origins, with possible distant relations to bacterial binding proteins.
• The research elucidates the transcriptional regulation, glycosylation, and subcellular localization of MbMNPV GP37, contributing to understanding baculovirus replication and pathogenesis.