GP64 is the key membrane fusion protein of Group I baculovirus, and while the Bombyx mori nucleopolyhedrovirus (BmNPV) GP64 contains a longer n-region (18 amino acid) of the signal peptide than does the Autographa californica multiple nucleopolyhedrovirus (AcMNPV), the function of the n-region has not been determined. In this study, we first showed that n-region is required for membrane protein localization in BmN cells, then the transcriptome sequencing was conducted on proteins guided by different signal peptide regions, and the results were analyzed and validated by quantitative PCR and luciferase assays. The results indicated that 1049 differentially expressed genes (DEGs) were identified among the different region of signal peptides and the control. With the n-region, the protein export pathway was upregulated significantly, the Wnt-1 signaling pathway was downregulated, and BiP was significantly activated by the GP64 full-length signal peptide. Furthermore, RNA interference on BiP efficiently increased luciferase secretion. These results indicate that the GP64 n-region plays a key role in protein expression and regulation.

中文翻译：

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家蚕核多角体病毒 GP64 信号肽的 18 种其他氨基酸通过 RNA-seq 分析激活免疫球蛋白结合蛋白 (BiP) 表达

GP64 是 I 组杆状病毒的关键膜融合蛋白，虽然家蚕核多角体病毒 (BmNPV) GP64 包含比 Autographa californica 多核多角体病毒 (AcMNPV) 更长的信号肽 n 区（18 个氨基酸），但功能n 区域尚未确定。在这项研究中，我们首先表明 n 区是 BmN 细胞膜蛋白定位所必需的，然后对由不同信号肽区域引导的蛋白质进行转录组测序，并通过定量 PCR 和荧光素酶测定对结果进行分析和验证。结果表明，在信号肽不同区域与对照之间共鉴定出1049个差异表达基因（DEGs）。对于 n 区，蛋白质输出途径显着上调，Wnt-1 信号通路被下调，BiP 被 GP64 全长信号肽显着激活。此外，对 BiP 的 RNA 干扰有效地增加了荧光素酶的分泌。这些结果表明 GP64 n 区在蛋白质表达和调节中起关键作用。