摘要
目的:通过免疫沉淀联合质谱分析的方法筛选发热伴血小板减少综合征病毒(SFTSV)非结构蛋白(NSs)的宿主互相作用(互作)蛋白,探讨互作蛋白的功能、亚细胞定位及参与的生物途径,为阐明SFTSV的复制和致病机制提供依据。方法:将真核表达载体pSFTSV-NSs-Flag (实验组)和Flag-CMV-3 (阴性组)分别转染进人胚胎肾293T细胞中,同时设置空白组(不进行任何处理)。收集各组细胞裂解液,采用间接免疫荧光和Western blotting法验证SFTSV NSs在宿主细胞中的表达及定位。蛋白裂解液经protein A/G处理,采用免疫沉淀法富集与NSs结合的宿主蛋白,通过银染和考马斯亮蓝染色初步分析捕获的互作蛋白,观察各组蛋白差异条带。采用液相色谱和串联质谱技术得到蛋白质的序列信息,保留可信蛋白基于UniProt数据库检索,对鉴定到的蛋白进行基因本体论(GO)功能富集分析、蛋白结构域和功能位点数据库(IPR)、真核生物同源蛋白簇(KOGs)功能注释、京都基因与基因组百科全书(KEGG)信号通路富集分析、亚细胞定位和转录因子(TF)功能注释,确定互作蛋白的亚细胞结构、基因功能及参与的生物过程。结果:SFTSV NSs在相对分子质量33 000处表达单一特异性条带,免疫荧光检测其定位于细胞质中,且聚集呈砂粒体包涵体样。银染和考马斯亮蓝染色,实验组和阴性组均存在显著差异条带。质谱筛选出46种潜在互作蛋白;GO功能富集分析、KOGs功能注释和KEGG信号通路富集分析,与病毒翻译、细胞代谢及蛋白质运输相关的生物途径富集到较多数目的蛋白,注释中有8种蛋白具有中间丝蛋白结构域。亚细胞定位所占百分率最高的是细胞质蛋白;与NSs定位场所一致。TF功能注释,有1种蛋白来自NF-Y家族。结论:互作蛋白在协助蛋白质正确折叠、参与核糖体翻译和构成细胞骨架等进程中发挥作用,可能参与了抗病毒复制,可作为候选蛋白进一步研究SFTSV的复制机制。
Objective:To screen the host interaction proteins of the severe fever with thrombocytopenia syndrome virus(SFTSV)nonstructural protein(NSs)by immunoprecipitation combined with mass spectrometry analysis,to discuss the functions,subcellular localization,and biological pathways of these interaction proteins,and to provide the basis for clarifying the replication and pathogenic mechanism of SFTSV.Methods:The eukaryotic expression vectors pSFTSV-NSs-Flag(experimental group)and Flag-CMV-3(negative group)were transfected into the human embryonic kidney 293T cells,and contorl group(no treatment)was set up.The lysates of the cells in various groups were collected,and the expression and localization of SFTSV NSs in the host cells were verified by indirect immunofluorescence and Western blotting methods.The protein lysates were treated with protein A/G and immunoprecipitation was used to enrich host proteins binding to NSs.The captured interaction proteins were initially analyzed by silver staining and Coomassie brilliant blue staining to observe the differential protein bands in various groups;liquid chromatography-tandem mass spectrometry was used to obtain the information of protein sequences;the reliable proteins were retained and searched by UniProt database;Gene Ontology(GO)functional enrichment analysis,IPR,eukaryotic orthologous groups(KOGs)functional annotation,Kyoto Encyclopedia of Genes and Genomes(KEGG)signaling pathway enrichment analysis,subcellular localization,and transcription factor(TF)functional annotation were used to determine the subcellular structure,gene functions,and biological processes of the interaction proteins.Results:The immunofluorescence results showed that the SFTSV NSs expressed a single specific band at relative molecular mass 33000 and was localized in the cytoplasm in a granular inclusion body-like manner.The silver staining and Coomassie brilliant blue staining results showed there were significant differential protein bands between experimental group and negative group.The mass spectrometry results identified 46 potential interaction proteins.The GO functional enrichment analysis,KOGs functional annotation,and KEGG signaling pathway enrichment analysis results showed that the biological pathways related to viral translation,cellular metabolism,and protein transport were enriched with a considerable number of proteins.Eight annotated proteins had intermediate filament domains.The highest percentage of subcellular localization was cytoplasmic proteins,consistent with the NSs localization site.The TF functional annotation analysis results showed one protein from the NF-Y family.Conclusion:The interaction proteins play roles in assisting the proper protein folding,participating in the cribosome translation,and forming the cytoskeleton,which may be involved in antiviral replication.These proteins can be used as candidate proteins for further study on the replication mechanism of SFTSV.
作者
骆丽可
程子文
程廓
李永刚
王大为
杨宝玲
LUO Like;CHENG Ziwen;CHENG Kuo;LI Yonggang;WANG Dawei;YANG Baoling(Department of Pathogen Biology,School of Basic Medical Sciences,Jinzhou Medical University,Jinzhou 121000,China;Department of Basic Veterinary Medicine,School of Animal Husbandry and Veterinary Medicine,Jinzhou Medical University,Jinzhou 121000,China)
出处
《吉林大学学报（医学版）》
CAS
CSCD
北大核心
2024年第5期1286-1296,共11页
Journal of Jilin University：Medicine Edition
基金
辽宁省科技厅科学技术计划项目(2022-BS-325)。
关键词
发热伴血小板减少综合征病毒
非结构蛋白
蛋白-蛋白互相作用
免疫沉淀
质谱
Severe fever with thrombocytopenia syndrome virus
Non-structural protein
Protein-protein interaction
Immunoprecipitation
Mass-spectrometric technique
