Study On The Correlation Between Swine Jiv Protein Expression And Classical Swine Fever Virus Infection

J-Domain protein interacting with virus (Jiv) also terms as cIns, DNAJC14, DRiP78, isone kind of intracellular molecular, and belongs to the family of Heat shock protein40(HSP40). It participates in modulating material transportation in cells and has a greatinfluence on the replication of Flaviviridae family members through interacting with the viralprotein or viral replication complex. Recently, the studies have found that one segment of Jivgene inserted into the genome of CSFV has a great influence on the replication and virulenceof CSFV, but their mechanism is not clear. Especially, the role of Jiv protein in CSFVinfection still needs further study. Other researches were showed that Jiv gene wasoverexpression, which can promote the replication of CSFV in cells. On the other hand, theJiv gene expression was interfered in cells, which leads to the down regulation of CSFVreplication. Moreover, this kind of correlationship differs in various tissues. However, there isstill short of direct evidence that expression quantity of Jiv protein was related to theproliferation quantity of CSFV. Based on this information, we infected the experimental pigs,when the typical CSF symptoms were appeared; Different kinds of tissue were collected usingthe immunohistochemistry method to detect swine Jiv protein and CSFV, and analyzing thecorrelation between swine Jiv protein expression and CSFV infection. The results are asfollow:(1)The core section gene of swine Jiv was amplified. The expressed protein was analyzedby using the bioinformatics software. It was showed that it has3transmembrane helixes, andthe both terminals of helixes could be used as the antigenic recognition sets. After comparedwith the protein sequence of known swine Jiv, human Jiv and cattle Jiv, it was found that thesequence similarity stood at100%，90%and91%, respectively, and shared similar tertiarystructure.(2)The constructed pET32a-Jiv was transmitted into Rosetta cells. After induced by IPTG,a great amount of recombinant swine Jiv protein was obtained after the purification andrenaturation procedures. By using the recombinant swine Jiv protein to immunizeexperimental rabbits, we acquired the polyclonal antibody of swine Jiv protein. The titer of antibodies was up to1:6400. The concentration of swine Jiv protein in different tissues andorgans was determinated with Western blot method. The results suggested that thecorresponding target bands clearly existed in kidney, heart, spleen and lymph node.(3) With the location detection of swine Jiv protein and CSFV, it was found that thepositive reaction substances appeared in all kinds of tissues and organs. Moreover, thecorrelation between the expression of swine Jiv protein and viral load of CSFV was positivein renal tubular epithelial cells, intestinal epithelial cell, gastric epithelial cells, bronchialepithelial cells, alveolar epithelial cells, neuron, liver cell and cardiac muscle fiber.Meanwhile, the consequence that the low level of swine Jiv protein accompanied with thehigh level of CSFV load in spleen and lymph node cue that the viral load of CSFV has adramatic increase under the related level of swine Jiv protein.Overall, this study prepared the polyclonal antibody of swine Jiv protein, and detectedCSFV load and swine Jiv protein expression in different tissues and organs withimmunohistochemistry method. It was found that the correlation between swine Jiv proteinexpression and CSFV load are positive in tissues and organs, which reminds us that swine Jivprotein may play a crucial role in the infection and replication of CSFV. This study offers afundamental evidence for the further studying the effects of Jiv protein in CSFV infection.