State Key Laboratory of Silkworm Genome Biology, Biological Science Research Center, Southwest University, Chongqing, China.
Chongqing Key Laboratory of Sericultural Science, Chongqing Engineering and Technology Research Center for Novel Silk Materials, Southwest University, Chongqing, China.
Front Immunol. 2022 Feb 7;13:807097. doi: 10.3389/fimmu.2022.807097. eCollection 2022.
Translationally controlled tumor protein (TCTP) is a highly conserved protein possessing numerous biological functions and molecular interactions, ranging from cell growth to immune responses. However, the molecular mechanism by which TCTP regulates immune function is largely unknown. Here, we found that knockdown of translationally controlled tumor protein () led to the increased susceptibility of silkworm cells to virus infection, whereas overexpression of significantly decreased the virus replication. We further demonstrated that could be modified by SUMOylation molecular BmSMT3 at the lysine 164 the conjugating enzyme BmUBC9, and the stable SUMOylation of by expressing -BmSMT3 fusion protein exhibited strong antiviral activity, which confirmed that the SUMOylation of would contribute to its immune responses. Further work indicated that is able to physically interact with interleukin enhancer binding factor (ILF), one immune molecular, involved in antivirus, and also induce the expression of in response to virus infection, which in turn enhanced antiviral activity of . Altogether, our present study has provided a novel insight into defending against virus SUMOylation signaling pathway and interacting with key immune molecular in silkworm.
翻译控制肿瘤蛋白（TCTP）是一种高度保守的蛋白质，具有许多生物学功能和分子相互作用，从细胞生长到免疫反应。然而，TCTP 调节免疫功能的分子机制在很大程度上是未知的。在这里，我们发现敲低 TCTP（翻译控制肿瘤蛋白）会导致家蚕细胞对病毒感染的敏感性增加，而过表达 TCTP 则显著降低病毒复制。我们进一步证明，TCTP 可以被 SUMO 修饰酶 BmUBC9 识别并修饰，在赖氨酸 164 上发生 SUMO 化修饰。表达 -BmSMT3 融合蛋白可以稳定地对 TCTP 进行 SUMO 化修饰，表现出很强的抗病毒活性，这证实了 TCTP 的 SUMO 化修饰有助于其免疫反应。进一步的研究表明，TCTP 能够与参与抗病毒的免疫分子白细胞介素增强因子结合因子（ILF）发生物理相互作用，并且能够响应病毒感染诱导自身的表达，从而增强抗病毒活性。总之，本研究为家蚕抵御病毒提供了一个新的视角，即 SUMO 化信号通路和与关键免疫分子的相互作用。
