Bombyx mori voltage‐dependent anion‐selective channel induces programmed cell death to defend against Bombyx mori nucleopolyhedrovirus infection

• Published in: Pest management science 2024-08, Vol.80 (8), p.3752-3762
• Main Authors: Lv, Jun‐li, Lai, Wen‐qing, Gong, Yu‐quan, Zheng, Kai‐yi, Zhang, Xiao‐ying, Lu, Zhan‐peng, Li, Mu‐wang, Wang, Xue‐yang, Dai, Li‐shang
• Format: Article
• Language: English
• Subjects: Anions; Apoptosis; Baculoviridae; Biological control; BmNPV; BmVDAC; Bombyx mori; Cell death; Disease resistance; Electric potential; Embryogenesis; Embryonic growth stage; Gene expression; Infections; Insects; Larvae; Malpighian tubules; Midgut; Molecular modelling; Mortality; Pest control; Pest resistance; programmed cell death; response mechanism; RNA viruses; RNA-mediated interference; Silkworms; Voltage
• ISSN: 1526-498X; 1526-4998; 1526-4998
• DOI: 10.1002/ps.8082

BACKGROUND Voltage‐dependent anion‐selective channels (VDACs) serve as pore proteins within the mitochondrial membrane, aiding in the regulation of cell life and cell death. Although the occurrence of cell death is crucial for defense against virus infection, the function played by VDAC in Bombyx mori, in response to the influence of Bombyx mori nucleopolyhedrovirus (BmNPV), remains unclear. RESULTS BmVDAC was found to be relatively highly expressed both during embryonic development, and in the Malpighian tubule and midgut. Additionally, the expression levels of BmVDAC were found to be different among silkworm strains with varying levels of resistance to BmNPV, strongly suggesting a connection between BmVDAC and virus infection. To gain further insight into the function of BmVDAC in BmNPV, we employed RNA interference (RNAi) to silence and overexpress it by pIZT/V5‐His‐mCherry. The results revealed that BmVDAC is instrumental in developing the resistance of host cells to BmNPV infection in BmN cell‐line cells, which was further validated as likely to be associated with initiating programmed cell death (PCD). Furthermore, we evaluated the function of BmVDAC in another insect, Spodoptera exigua. Knockdown of the BmVDAC homolog in S. exigua, SeVDAC, made the larvae more sensitive to BmNPV. CONCLUSION We have substantiated the pivotal role of BmVDAC in conferring resistance against BmNPV infection, primarily associated with the initiation of PCD. The findings of this study shine new light on the molecular mechanisms governing the silkworm's response to BmNPV infection, thereby supporting innovative approaches for pest biocontrol. © 2024 Society of Chemical Industry. The excessive expression of the BmVDAC triggers reactive oxygen species activation and facilitates the release of apoptotic factors from mitochondria. This subsequently results in an elevation in caspase‐3 levels, which governs programmed cell death as a defense mechanism against BmNPV.