Comprehensive analysis of the succinylome in Vero cells infected with peste des petits ruminants virus Nigeria 75/1 vaccine strain

Abstract

Background: Peste des petits ruminants virus (PPRV) is currently the only member of the Morbillivirus caprinae species within the genus Morbillivirus of the family Paramyoxviridae. PPRV causes a highly contagious disease in small ruminants, especially goats and sheep. Succinylation is a newly identified and conserved modification and plays an important role in host cell response to pathogen infection. However, the extent and function of succinylation in Vero cells during PPRV infection remains unknown.

Results: In this study, a global profile of the succinylome in Vero cells infected with PPRV Nigeria 75/1 vaccine strain (PPRVvac) was performed by dimethylation labeling-based quantitative proteomics analysis. A total of 2633 succinylation sites derived from 823 proteins were quantified. The comparative analysis of differentially succinylated sites revealed that 228 down-regulated succinylation sites on 139 proteins and 44 up-regulated succinylation sites on 38 proteins were significantly modified in response to PPRVvac infection, seven succinylation motifs were identified. GO classification indicated that the differentially succinylated proteins (DSuPs) mainly participated in cellular respiration, biosynthetic process and transmembrane transporter activity. KEGG pathway analysis indicated that DSuPs were related to protein processing in the endoplasmic reticulum. Protein-protein interaction networks of the identified proteins provided further evidence that various ATP synthase subunits and carbon metabolism were modulated by succinylation, while the overlapped proteins between succinylation and acetylation are involved in glyoxylate and dicarboxylate metabolism.

Conclusions: The findings of the present study provide the first report of the succinylome in Vero cells infected with PPRVvac and provided a foundation for investigating the role of succinylation alone and its overlap with acetylation in response to PPRVvac.

Keywords: Peste Des petits ruminants virus; Post-translational modification; Protein-protein interaction; Succinylation.

Fig. 1

The identification of succinylation proteins and sites. A peptide length distribution of succinylation profile; B Summary of the succinylated proteins and sites identified

Fig. 2

Characterization of succinylated peptides. A Probability sequence motifs of succinylation sites consisting of 20 residues surrounding the targeted lysine residue using Motif-X. Seven significantly enriched succinylation site motifs were identified; B Heat map showing upstream (red) or downstream (green) of amino acid compositions around the succinylated lysine site (10 amino acids upstream and downstream of the succinylated lysine site)

Fig. 3

Classification of the identified DSuPs. A Biological process; B Cellular component; C Molecular function; D Subcellular localization

Fig. 4

COG/KOG classification

Fig. 5

Enrichment of DSuPs. A Molecular function; B Cellular component; C Biological process. D: Protein domain

Fig. 6

PPI networks of DSuPs. Each node represented a protein, and each line referred to an interaction. Node colors represented fold change, and circle size represents the numbers of DSuPs, and red indicates upregulated and blue indicates downregulated DSuPs

Fig. 7

The crosstalk between the DSuPs and DAcPs in PPRVvac-infected vero cell

Fig. 8

The flowchart of virus infection, proteomic analysis and global mapping of succinylation in PPRVvac-infected Vero cells