Quantitative Proteomic Analysis of Porcine Intestinal Epithelial Cells Infected with Porcine Deltacoronavirus Using iTRAQ-Coupled LC-MS/MS

Porcine
deltacoronavirus (PDCoV) is an emergent enteropathogenic
coronavirus associated with swine diarrhea. Porcine small intestinal
epithelial cells (IPEC) are the primary target cells of PDCoV infection
in vivo. Here, isobaric tags for relative and absolute quantification
(iTRAQ) labeling coupled to liquid chromatography–tandem mass
spectrometry (LC-MS/MS) was used to quantitatively identify differentially
expressed proteins (DEPs) in PDCoV-infected IPEC-J2 cells. A total
of 78 DEPs, including 23 upregulated and 55 downregulated proteins,
were identified at 24 h postinfection. The data are available via
ProteomeXchange with identifier PXD019975. To ensure reliability of
the proteomics data, two randomly selected DEPs, the downregulated
anaphase-promoting complex subunit 7 (ANAPC7) and upregulated interferon-induced
protein with tetratricopeptide repeats 1 (IFIT1), were verified by
real-time PCR and Western blot, and the results of which indicate
that the proteomics data were reliable and valid. Bioinformatics analyses,
including GO, COG, KEGG, and STRING, further demonstrated that a majority
of the DEPs are involved in numerous crucial biological processes
and signaling pathways, such as immune system, digestive system, signal
transduction, RIG-I-like receptor, mTOR, PI3K-AKT, autophagy, and
cell cycle signaling pathways. Altogether, this is the first study
on proteomes of PDCoV-infected host cells, which shall provide valuable
clues for further investigation of PDCoV pathogenesis.

猪德尔塔冠状病毒（PDCoV）是一种新兴的肠道致病冠状病毒，与猪腹泻有关。猪小肠上皮细胞（IPEC）是PDCoV感染在体内的主要靶细胞。本研究采用等量标签相对和绝对定量（iTRAQ）标记联合液相色谱-串联质谱（LC-MS/MS）技术，对感染PDCoV的IPEC-J2细胞中差异表达蛋白（DEPs）进行定量分析。感染后24小时，共鉴定出78个DEPs，其中上调蛋白23个，下调蛋白55个。数据可通过ProteomeXchange平台（标识符为PXD019975）获取。为确保蛋白质组数据的可靠性，随机选取两个DEPs，即下调的子粒期促进复合物亚基7（ANAPC7）和上调的干扰素诱导的具有四肽重复结构域的蛋白1（IFIT1），通过实时PCR和蛋白质印迹法进行验证，结果表明蛋白质组数据可靠且有效。生物信息学分析，包括GO、COG、KEGG和STRING，进一步揭示大多数DEPs参与众多关键的生物学过程和信号通路，如免疫系统、消化系统、信号转导、RIG-I样受体、mTOR、PI3K-AKT、自噬和细胞周期信号通路。综上所述，本研究首次对PDCoV感染宿主细胞的蛋白质组进行了研究，为进一步探究PDCoV的致病机制提供了宝贵线索。