Xiao Peiyu, Meng Liang, Cui Xingyang, Liu Xinran, Qin Lei, Meng Fandan, Cai Xuehui, Kong Dongni, An Tongqing, Wang Haiwei
State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China.
Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, New York, NY 10591, USA.
Pathogens. 2024 Jul 21;13(7):601. doi: 10.3390/pathogens13070601.
Many picornaviruses require the myristoylation of capsid proteins for viral replication. Myristoylation is a site-specific lipidation to the N-terminal G residue of viral proteins, which is catalyzed by the ubiquitous eukaryotic enzyme N-myristoyltransferase (NMT) by allocating the myristoyl group to the N-terminal G residue. IMP-1088 and DDD85646 are two inhibitors that can deprive NMT biological functions. Whether Senecavirus A (SVA) uses NMT to modify VP0 and regulate viral replication remains unclear. Here, we found that NMT inhibitors could inhibit SVA replication. NMT1 knock-out in BHK-21 cells significantly suppressed viral replication. In contrast, the overexpression of NMT1 in BHK-21 cells benefited viral replication. These results indicated that VP0 is a potential NMT1 substrate. Moreover, we found that the myristoylation of SVA VP0 was correlated to the subcellular distribution of this protein in the cytoplasm. Further, we evaluated which residues at the N-terminus of VP0 are essential for viral replication. The substitution of N-terminal G residue, the myristoylation site of VP0, produced a nonviable virus. The T residue at the fifth position of the substrates facilitates the binding of the substrates to NMT. And our results showed that the T residue at the fifth position of VP0 played a positive role in SVA replication. Taken together, we demonstrated that SVA VP0 myristoylation plays an essential role in SVA replication.
许多小核糖核酸病毒的病毒复制需要衣壳蛋白的肉豆蔻酰化。肉豆蔻酰化是病毒蛋白N端甘氨酸残基的位点特异性脂化，由普遍存在的真核酶N-肉豆蔻酰转移酶（NMT）催化，将肉豆蔻酰基团分配到N端甘氨酸残基上。IMP-1088和DDD85646是两种可剥夺NMT生物学功能的抑制剂。A组赛尼卡病毒（SVA）是否利用NMT修饰VP0并调节病毒复制仍不清楚。在此，我们发现NMT抑制剂可抑制SVA复制。BHK-21细胞中的NMT1基因敲除显著抑制了病毒复制。相反，BHK-21细胞中NMT1的过表达有利于病毒复制。这些结果表明VP0是潜在的NMT1底物。此外，我们发现SVA VP0的肉豆蔻酰化与该蛋白在细胞质中的亚细胞分布相关。此外，我们评估了VP0 N端的哪些残基对病毒复制至关重要。VP0的肉豆蔻酰化位点N端甘氨酸残基的替换产生了无活性病毒。底物第5位的苏氨酸残基促进底物与NMT的结合。我们的结果表明，VP0第5位的苏氨酸残基在SVA复制中起积极作用。综上所述，我们证明SVA VP0肉豆蔻酰化在SVA复制中起重要作用。
