Rabies virus (RABV) is reported to encode five phosphoproteins (P), which are involved in viral genomic replication, axonal transport, oxidative stress, interferon antagonism, and autophagy induction. However, the functions of the different P proteins are poorly understood. Immunofluorescence staining and western blot were performed to detect the autophagy activity, the form of ring-like structure, and the colocalization of BECN1 and P. Co-immunoprecipitation was performed to detect the interaction between P and BECN1. QRT-PCR and TCID50 assay were performed to detect the replication level of RABV. Small interfering RNA was used to detect the autophagy signaling pathway. We found that P5 attaches to N-terminal residues 1–139 of BECN1 (beclin1) on the BECN1 ring-like structure through amino acid residues 173–222 of P5. Subsequently, we found that P5-induced autophagosomes did not fuse with lysosomes. Becn1 silencing did not recover P5 overexpression-induced promotion of RABV replication. Mechanistically, RABV protein PΔN82 (P5) induced incomplete autophagy via the BECN1-mediated signaling pathway. Our data indicate that P5 binding to the BECN1 ring benefits RABV replication by inducing BECN1 signaling pathway-dependent incomplete autophagy, which provides a potential target for antiviral drugs against RABV.

中文翻译：

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狂犬病病毒磷蛋白 P5 与 BECN1 结合通过 BECN1 介导的自噬信号通路调节自我复制。

据报道，狂犬病病毒 (RABV) 编码五种磷蛋白 (P)，它们参与病毒基因组复制、轴突运输、氧化应激、干扰素拮抗和自噬诱导。然而，人们对不同 P 蛋白的功能知之甚少。进行免疫荧光染色和蛋白质印迹检测自噬活性、环状结构的形式以及BECN1和P的共定位。进行共免疫沉淀以检测P和BECN1之间的相互作用。进行QRT-PCR和TCID50测定以检测RABV的复制水平。小干扰RNA用于检测自噬信号通路。我们发现 P5 通过 P5 的氨基酸残基 173-222 连接到 BECN1 环状结构上的 BECN1 (beclin1) 的 N 末端残基 1-139。随后，我们发现 P5 诱导的自噬体没有与溶酶体融合。Becn1 沉默没有恢复 P5 过表达诱导的 RABV 复制促进。从机制上讲，RABV 蛋白 PΔN82 (P5) 通过 BECN1 介导的信号通路诱导不完全自噬。我们的数据表明，与 BECN1 环结合的 P5 通过诱导 BECN1 信号通路依赖的不完全自噬有利于 RABV 复制，这为抗 RABV 的抗病毒药物提供了潜在的靶点。