State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China.
Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture, Southwest University, Chongqing, China.
Insect Sci. 2020 Jun;27(3):463-474. doi: 10.1111/1744-7917.12664. Epub 2019 Mar 7.
As an important insect immune response, apoptosis plays a critical role in the interaction between baculoviruses and insect hosts. Previous reports have identified inhibitor of apoptosis (IAP) proteins in both insects and baculoviruses, but the relationship between these proteins is still not clearly understood. Here, we found that insect IAP proteins were clustered with baculovirus IAP3, suggesting that the baculovirus iap3 gene might be derived from the Lepidoptera or Diptera. We demonstrated that Bombyx mori inhibitor of apoptosis (Bmiap) gene had an inhibitory effect on apoptosis in silkworm cells. Further analysis of the effects of Bmiap genes on the proliferation of B. mori nucleopolyhedrovirus (BmNPV) showed that both the Bmiap and BmNPV iap genes increased BmNPV proliferation after BmNPV infected silkworm cells. Our results also indicated that BmNPV IAP1 and IAP2 directly interacted with BmIAP in silkworm cells, implying that the Bmiap gene might be hijacked by BmNPV iap genes during BmNPV infection. Taken together, our results provide important insights into the functional relationships of iap genes, and improve our knowledge of apoptosis in baculoviruses and insect hosts.
作为昆虫重要的免疫反应之一，细胞凋亡在杆状病毒与昆虫宿主的相互作用中起着关键作用。先前的报道已经在昆虫和杆状病毒中鉴定出凋亡抑制蛋白（IAP），但这些蛋白之间的关系仍不清楚。在这里，我们发现昆虫 IAP 蛋白与杆状病毒 IAP3 聚集在一起，这表明杆状病毒 iap3 基因可能来源于鳞翅目或双翅目。我们证明了家蚕凋亡抑制蛋白（Bmiap）基因对家蚕细胞凋亡具有抑制作用。进一步分析 Bmiap 基因对家蚕核型多角体病毒（BmNPV）增殖的影响表明，Bmiap 和 BmNPV iap 基因都能增加 BmNPV 感染家蚕细胞后的增殖。我们的结果还表明，BmNPV IAP1 和 IAP2 在家蚕细胞中直接与 BmIAP 相互作用，这意味着在 BmNPV 感染过程中，Bmiap 基因可能被 BmNPV iap 基因劫持。总之，我们的研究结果为 iap 基因的功能关系提供了重要的见解，并提高了我们对杆状病毒和昆虫宿主中细胞凋亡的认识。
