Padarath Kiyasha, Deroubaix Aurélie, Naicker Previn, Stoychev Stoyan, Kramvis Anna
Hepatitis Virus Diversity Unit, Department of Internal Medicine, School of Clinical Medicine, Faculty of Health Science, University of Witwatersrand, 7 York Road, Johannesburg 2193, South Africa.
Life Sciences Imaging Facility, Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Johannesburg 2193, South Africa.
Curr Issues Mol Biol. 2024 Jul 4;46(7):7032-7047. doi: 10.3390/cimb46070419.
HBeAg is a non-structural, secreted protein of hepatitis B virus (HBV). Its p25 precursor is post-translationally modified in the endoplasmic reticulum. The G1862T precore mutation leads to the accumulation of P25 in the endoplasmic reticulum and activation of unfolded protein response. Using mass spectrometry, comparative proteome profiling of Huh-7 cells transfected with wildtype (WT) or G1862T revealed significantly differentially expressed proteins resulting in 12 dysregulated pathways unique to WT-transfected cells and 7 shared between cells transfected with either WT or G1862T. Except for the p38 MAPK signalling pathway, WT showed a higher number of DEPs than G1862T-transfected cells in all remaining six shared pathways. Two signalling pathways: oxidative stress and cell cycle signalling were differentially expressed only in cells transfected with G1862T. Fifteen pathways were dysregulated in G1862T-transfected cells compared to WT. The 15 dysregulated pathways were involved in the following processes: MAPK signalling, DNA synthesis and methylation, and extracellular matrix organization. Moreover, proteins involved in DNA synthesis signalling (replication protein A (RPA) and DNA primase (PRIM2)) were significantly upregulated in G1862T compared to WT. This upregulation was confirmed by mRNA quantification of both genes and immunofluorescent confocal microscopy for RPA only. The dysregulation of the pathways involved in these processes may lead to immune evasion, persistence, and uncontrolled proliferation, which are hallmarks of cancer.
乙肝e抗原（HBeAg）是乙型肝炎病毒（HBV）的一种非结构分泌蛋白。其p25前体在内质网中进行翻译后修饰。G1862T前核心突变导致p25在内质网中积累并激活未折叠蛋白反应。使用质谱法，对转染野生型（WT）或G1862T的Huh-7细胞进行比较蛋白质组分析，结果显示存在显著差异表达的蛋白质，导致WT转染细胞有12条失调途径，WT或G1862T转染细胞共有7条失调途径。除p38丝裂原活化蛋白激酶（MAPK）信号通路外，在其余所有六条共有途径中，WT显示出比G1862T转染细胞更多的差异表达蛋白（DEP）。两条信号通路：氧化应激和细胞周期信号通路仅在G1862T转染的细胞中差异表达。与WT相比，G1862T转染细胞中有15条途径失调。这15条失调途径涉及以下过程：MAPK信号传导、DNA合成和甲基化以及细胞外基质组织。此外，与WT相比，参与DNA合成信号传导的蛋白质（复制蛋白A（RPA）和DNA引物酶（PRIM2））在G1862T中显著上调。仅通过对这两个基因的mRNA定量以及仅对RPA进行免疫荧光共聚焦显微镜检查证实了这种上调。这些过程中涉及的途径失调可能导致免疫逃逸、持续性和不受控制的增殖，而这些都是癌症的特征。
