Amalfi Sabrina, Plastine María Del Pilar, López María Gabriela, Gravisaco María José, Taboga Oscar, Alfonso Victoria
Instituto de Agrobiotecnología y Biología Molecular (IABIMO), Instituto Nacional de Tecnología Agropecuaria (INTA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), De los Reseros y N. Repetto s/n, B1686IGC, Hurlingham, Buenos Aires, Argentina.
Instituto de Biotecnología, Universidad Nacional de Hurlingham, Av. Vergara 2222, Villa Tesei, B1688GEZ, Hurlingham, Buenos Aires, Argentina.
Appl Microbiol Biotechnol. 2023 Oct;107(20):6277-6286. doi: 10.1007/s00253-023-12703-0. Epub 2023 Aug 14.
Poxins are poxviral proteins that act by degrading 2´3´-cGAMP, a key molecule of cGAS-STING axis that drives and amplifies the antiviral response. Previous works have described some poxin homologous among lepidopteran and baculoviral genes. In particular, P26, a poxin homologous from AcMNPV retains the 2´3´-cGAMP degradation activity in vitro. In this work, we demonstrated that the antiviral activity triggered by baculovirus was disrupted by the transient expression of P26 in murine and human cell lines, and the effect of this action is not only on IFN-β production but also on the induction of IFN-λ. Besides, we proved P26 functionality in a stable-transformed cell line where the protein was constitutively expressed, preventing the production of IFN-β induced by baculovirus and resulting in an improvement in the transduction efficiency by the attenuation of the antiviral activity. Finally, we incorporated P26 into budded virions by capsid display or passive incorporation, and the results showed that both strategies resulted in an improvement of 3-17 times in the efficiency of transgene expression in murine fibroblasts. Our results suggest that the incorporation of P26 to budded baculoviral vectors is a very promising tool to modulate negatively the innate antiviral cellular response and to improve the efficiency of gene delivery in mammalian cells. KEY POINTS: • P26 affects baculovirus-induced IFN-β and IFN-λ production in mammalian cells. • Murine fibroblasts expressing P26 are more susceptible to transduction by baculovirus. • Incorporation of P26 into the virion improves gene delivery efficiency of baculovirus.
痘病毒蛋白是痘病毒的蛋白质，其作用是降解2´3´-cGAMP，2´3´-cGAMP是cGAS-STING轴的关键分子，可驱动和放大抗病毒反应。先前的研究已经描述了鳞翅目和杆状病毒基因中的一些痘病毒蛋白同源物。特别是，来自苜蓿银纹夜蛾核型多角体病毒（AcMNPV）的痘病毒蛋白同源物P26在体外保留了2´3´-cGAMP降解活性。在这项研究中，我们证明了杆状病毒触发的抗病毒活性在小鼠和人类细胞系中被P26的瞬时表达所破坏，并且这种作用的影响不仅在于干扰素-β（IFN-β）的产生，还在于干扰素-λ（IFN-λ）的诱导。此外，我们在稳定转化的细胞系中证明了P26的功能，该细胞系中该蛋白被组成性表达，可阻止杆状病毒诱导的IFN-β产生，并通过减弱抗病毒活性提高转导效率。最后，我们通过衣壳展示或被动掺入将P26整合到出芽的病毒粒子中，结果表明这两种策略均使小鼠成纤维细胞中转基因表达效率提高了3至17倍。我们的结果表明，将P26整合到出芽的杆状病毒载体中是一种非常有前景的工具，可负面调节先天性抗病毒细胞反应并提高哺乳动物细胞中的基因递送效率。要点：•P26影响杆状病毒诱导的哺乳动物细胞中IFN-β和IFN-λ的产生。•表达P26的小鼠成纤维细胞对杆状病毒的转导更敏感。•将P26整合到病毒粒子中可提高杆状病毒的基因递送效率。
