Inhibition of BmNPV proliferation by Bombyx mori ADP/ATP transportase (BmANT)

Abstract:

[Objective] Bombyx mori nucleopolyhedrovirus (BmNPV) belongs to the family Baculoviridae. It replicates and proliferates using its host cell's energy metabolism. Bombyx mori ADP/ATP translocase (BmANT) is a transporter that interacts with the host energy metabolism factor, heat shock protein 60 (BmHSP60), during BmNPV infection. To determine which of the functional characteristics of the Bmant gene affect the process of BmNPV infection, we here analyze the mechanism by which the baculovirus hijacks host cytokines to promote viral proliferation and replication. [Methods] The structural characteristics of the Bmant gene were predicted, and qRT-PCR was performed to analyze the changes in the Bmant gene after BmNPV infection. The effect of this gene on viral DNA replication and viral protein expression was analyzed using overexpression of the Bmant gene. We further analyzed the relationship between the Bmant and Bmhsp60 genes in transcriptional regulation. The mechanism by which Bmant and Bmhsp60 regulates the proliferation and replication of BmNPV was identified using flow cytometry and Western blotting analysis. [Results] SMART software predicted that BmANT protein contained three mitochondrial vector domains, and the Bmant gene down-regulated expression 24 h after BmNPV infection. Overexpression of the Bmant gene significantly inhibited BmNPV DNA replication and VP39 protein expression. QRT-PCR analysis showed the Bmant and Bmhsp60 genes to have mutual antagonism and to be capable of inhibiting each other's transcription. Co-transfection analysis of the Bmant and Bmhsp60 genes showed that the Bmant gene can significantly inhibit the action of the Bmhsp60 gene and ultimately inhibit the proliferation and replication of BmNPV. [Conclusion] The results indicated that the Bmant gene is a mitochondrial carrier protein with significant antiviral activity that is capable of down-regulating the expression of Bmhsp60 and inhibiting BmNPV proliferation and replication.