Proteomics And Lactylome Analyses Of IPEC-J2 Cells Under PDCoV Infection

Porcine deltacoronavirus(PDCoV),a member of the genus Coronavirus in the family Coronaviridae of the order Cepoviridae,is endemic in many regions of the world and is capable of causing diarrhea,dehydration,and even death in piglets.In 2012,PDCoV was first identified and reported in Hong Kong,China.There is no commercially available vaccine to provide effective immunological protection for pigs due to the vast range of natural hosts and the vulnerability of PDCoV to mutation,leading to the widespread virus and significant financial losses for the pig industrial.This investigation was carried out to discover differential proteins and differentially lactic acidification altered proteins after infection,and to uncover significantly regulated protein functions and signaling pathways using bioinformatics to reveal PDCoV infection and host response.According to our findings in 4D proteomics,a total of 6576 proteins were confirmed,of which 5423 could be quantified.35 of the quantifiable proteins were significantly upregulated and 7 were significantly down-regulated.Surprisely,the expression of immunerelated proteins such as ISG15,IFIT3,OAS1,and HERC5 increased very dramatically.Differential proteins were predominantly engaged in the immune system and defensive response,according to further investigations such as functional classification and enrichment of differential proteins.Meanwhile,a total of 46 quantitative lactation modification sites with significant differences,including 4 up-regulated and 42 down-regulated sites,were found in as lactylome results,which identified 4351 lactation modification sites in 1707 proteins.Of these,3335 sites in 1399 proteins could be precisely quantified.The functional classification and enrichment analysis of variably lactylated modified proteins revealed a relationship between the occurrence of lactylated proteins and events such as catabolic regulation of mRNA.The inhibitors TS A and apicidin were also utilized in this study to explore the impact of lactylation modification on the replication of PDCoV infection and the lower lactylation modification level.Infection supernatants were harvested and virus titers were measured by the plaque method.The results showed that the level of virus replication was significantly reduced after treatment with the HDAC1-3 specific inhibitor apicidin,and the diameter of plaque formed after drug treatment was significantly smaller than that of the virus-infected control group,indicating that lactylation modification may be involved the host host resistance mechanisms.In conclusion,the findings of our work may provide novel theoretical insight and innovative concepts for the investigation of PDCoV’s pathogenic mechanism,immune regulation,and antiviral target screening.