Huang Yi-Heng, Guo Xin-Lu, Shan Meng-Ke, Yang Gui-Wen, Yang Hui-Ting
Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, Jinan, China.
J Virol. 2025 Mar 18;99(3):e0170024. doi: 10.1128/jvi.01700-24. Epub 2025 Feb 5.
Class B scavenger receptors (SRBs) have been well-studied in bacteria-induced immune responses in invertebrates. However, the status of SRB-defending viruses remains unclear. In this study, we identified a scavenger receptor in (crayfish), which is homologous to mammalian SRBs, and designated it as SRB. The expression of SRB was upregulated after the WSSV challenge. The survival rate of crayfish was decreased, but the WSSV copy number increased after SRB knockdown during virus invasion. In addition, SRB bound to WSSV. Furthermore, we detected how SRB interacted with WSSV, and we found that SRB could bind to cholesta-3,5-diene, (CD3,5), a novel WSSV lipid ligand, rather than dibutyl phthalate (DBP). Besides, SRB could bind to VP19, VP26, and VP28, rather than VP24. Mutant-binding experiments demonstrated that the hydrophobic domain (130-180 aa) of SRB is important for recognizing WSSV. Furthermore, SRB might promote lysosomal eliminating function to degrade WSSV. Altogether, we identified a new mechanism for scavenger receptor recognition and resistance to WSSV.IMPORTANCESRB could bind to WSSV directly. SRB could interact with WSSV via binding to lipid molecule CD3,5 and viral envelope proteins. SRB could influence lysosomal activation.
B类清道夫受体（SRBs）在无脊椎动物细菌诱导的免疫反应中已得到充分研究。然而，SRB对病毒防御的状况仍不清楚。在本研究中，我们在小龙虾中鉴定出一种与哺乳动物SRBs同源的清道夫受体，并将其命名为SRB。在白斑综合征病毒（WSSV）攻击后，SRB的表达上调。在病毒入侵期间，SRB敲低后小龙虾的存活率下降，但WSSV拷贝数增加。此外，SRB与WSSV结合。此外，我们检测了SRB与WSSV的相互作用方式，发现SRB可以与一种新型WSSV脂质配体胆甾-3,5-二烯（CD3,5）结合，而不是与邻苯二甲酸二丁酯（DBP）结合。此外，SRB可以与VP19、VP26和VP28结合，而不是与VP24结合。突变体结合实验表明，SRB的疏水结构域（130-180氨基酸）对于识别WSSV很重要。此外，SRB可能促进溶酶体的清除功能以降解WSSV。总之，我们确定了清道夫受体识别和抵抗WSSV的新机制。重要性SRB可以直接与WSSV结合。SRB可以通过与脂质分子CD3,5和病毒包膜蛋白结合来与WSSV相互作用。SRB可以影响溶酶体的激活。
