Abstract：
Bombyx mori nucleopolyhedrovirus (BmNPV) significantly impacts silkworm sericulture, causing substantial economic losses. The GP64 protein, a primary envelope protein of BmNPV budded virus (BV), retains its signal peptide (SP) in the mature form, crucial for its translocation to the plasma membrane (PM) and viral infectivity. This study investigates the role of the uncleaved SP of GP64 in activating the expression of BmSpz7, a novel Spätzle family member identified through RNA-seq analysis. We cloned and characterized BmSpz7, demonstrating its upregulated expression in BmN cells and silkworm larvae infected with BmNPV containing GP64 with an uncleaved SP. Additionally, transient expression of GP64\'s SP significantly enhanced BmSpz7 expression and protein secretion. These findings suggest that the uncleaved SP of GP64 plays a pivotal role in activating BmSpz7, providing new insights into the molecular interactions between BmNPV and its host, and revealing potential targets for antiviral strategies in sericulture.
摘要：
家蚕核型多角体病毒(BmNPV)显著影响蚕桑,造成了巨大的经济损失。GP64蛋白，BmNPV芽病毒（BV）的主要包膜蛋白，以成熟形式保留其信号肽（SP），对于其易位到质膜（PM）和病毒感染性至关重要。这项研究调查了GP64的未切割SP在激活BmSpz7表达中的作用，BmSpz7是通过RNA-seq分析鉴定的新型Spätzle家族成员。我们克隆了BmSpz7并对其进行了表征，证明了其在BmN细胞和用含GP64的BmNPV感染的家蚕幼虫中的表达上调。此外,GP64的SP瞬时表达显著增强了BmSpz7的表达和蛋白分泌。这些发现表明，GP64的未裂解的SP在激活BmSpz7中起着关键作用，为BmNPV与其宿主之间的分子相互作用提供了新的见解。并揭示蚕桑抗病毒策略的潜在目标。
