Background Japanese encephalitis virus is a mosquito-borne neurotropic flavivirus that causes acute viral encephalitis in humans. Pigs are crucial amplifier host of JEV. Recently, increasing evidence has shown that long non-coding RNAs (lncRNAs) play important roles in virus infection. Methods JEV proliferation was evaluated after overexpression or knockdown of lncRNA-SUSAJ1 using western blotting and reverse-transcription polymerase chain reaction (RT-PCR). C–C chemokine receptor type 1 (CCR1) was found to regulate the expression of lncRNA-SUSAJ1 by inhibitors screen. The expression of lncRNA-SUSAJ1 was detected using RT-PCR after overexpression or knockdown of transcription factor SP1. In addition, the enrichments of transcription factor SP1 on the promoter of lncRNA-SUSAJ1 were analyzed by chromatin immunoprecipitation. Results In this study, we demonstrated that swine lncRNA-SUSAJ1 could suppress JEV proliferation in PK-15 cells. We also found that CCR1 inhibited the expression of lncRNA-SUSAJ1 via the transcription factor SP1. In addition, knockdown of CCR1 could upregulated the expression of SP1 and lncRNA-SUSAJ1, resulting in resistance to JEV proliferation. Conclusions These findings illustrate the importance of lncRNAs in virus proliferation, and reveal how this virus regulates lncRNAs in host cells to promote its proliferation.

Bacillus licheniformis (B. licheniformis) is a well-accepted probiotic that has many benefits on both humans and animals. This study explored the effects of B. licheniformis on growth performance, intestinal mucosal barrier functions, immunity as well as serum metabolome in the weaned piglets exposed to lipopolysaccharide (LPS). One hundred and twenty piglets weaned at four weeks of age were separated into two groups that received a basal diet (the control group, CON), and a basal diet complemented with B. licheniformis (500 mg/kg, the BL group, BL). Twenty-four piglets were chosen from the above two groups and 12 piglets were injected with LPS intraperitoneally at a concentration of 100 μg/kg and the others were injected with sterile saline solution of the same volume. All the piglets were sacrificed 4 h after LPS challenge. Results showed that B. licheniformis enhanced the ADG and final body weight and lowered the F/G and diarrhea rate. Pre-treatment with B. licheniformis markedly attenuated intestinal mucosal damage induced by LPS challenge. Supplementation with B. licheniformis strengthened immune function and suppressed inflammatory response by elevating the concentrations of serum immunoglobulin (Ig) A and jejunum mucosal IgA and IgG and decreasing serum IL-6 and jejunum mucosal IL-1β. In addition, B. licheniformis pretreatment prevented LPS-induced intestinal injury by regulating the NLRP3 inflammasome. Furthermore, pretreatment with B. licheniformis tended to reverse the reduction of acetate and propionic acids in the colonic contents that occurred due to LPS stress. B. licheniformis markedly modulated the metabolites of saccharopine and allantoin from lysine and purine metabolic pathways, respectively. Overall, these data emphasize the potentiality of B. licheniformis as a dietary supplement to overcome the challenge of bacterial LPS in the animal and to enhance the food safety.

Promyelocytic leukemia (PML) protein is a crucial component of PML-nuclear bodies (PML-NBs). PML and PML-NBs are involved in the regulation of various cellular functions, including the antiviral immune response. The human PML gene can generate several different isoforms through alternative splicing. However, little is known about the porcine PML alternative splicing isoforms and their expression profiles during Japanese encephalitis virus (JEV) infection. In the present study, we cloned seven mature transcripts of porcine PML, all of which contained the same N-terminal sequence but differed in the C-terminal sequences due to alternative splicing. These seven transcripts encoded five proteins all of which had the RBCC motif and sumoylation sites. Amino acid sequence homology analysis showed that porcine PML-1 had relatively high levels of identity with human, cattle, and goat homologs (76.21, 77.17, and 77.05%, respectively), and low identity with the mouse homolog (61.78%). Immunofluorescence analysis showed that the typical PML-NBs could be observed after overexpression of the five PML isoforms in PK15 cells. Quantitative reverse transcription PCR (RT-qPCR) analysis showed significant upregulation of PML isoforms and PML-NB-associated genes (Daxx and SP100) at 36 and 48 h post-infection (hpi). Western blotting analysis indicated that the PML isoforms were upregulated during the late stage of infection. Moreover, the number of PML-NBs was increased after JEV infection. These results suggest that porcine PML isoforms may play essential roles in JEV infection.

Background: Japanese encephalitis virus is a mosquito-borne neurotropic flavivirus that causes acute viral encephalitis in humans. Pigs are crucial amplifier host of JEV. Recently, long non-coding RNAs have received increasing attention for their antiviral function. Methods: LncRNA-NONSUST006715.1 was overexpression or knockdown using western blotting and reverse-transcription polymerase chain reaction (RT-PCR) to detect the effect of lncRNA on JEV proliferation. CCR1 was found to regulate the expression of lncRNA-NONSUST006715.1 by inhibitors screen. Transcription factor SP1 was overexpression or knockdown using RT-PCR to detect the influence of SP1 on the expression of lncRNA. In addition, the enrichments of transcription factor SP1 on the promoter of lncRNA-NONSUST006715.1 were analyzed by Chromatin immunoprecipitation.Results: In this study, we demonstrated a new function of lncRNA-NONSUST006715.1, the inhibition of JEV proliferation in PK-15 cells. We found that C-C chemokine receptor type 1 inhibited the expression of lncRNA-NONSUST006715.1 via the transcription factor SP1. Knockdown of CCR1 could upregulated the expression of SP1 and lncRNA-NONSUST006715.1, resulting in resistance to JEV proliferation. Conclusions: These findings illustrate the importance of lncRNAs in virus proliferation, and reveal how this virus regulates lncRNAs in host cells to promote its proliferation.

Background: Japanese encephalitis virus is a mosquito-borne neurotropic flavivirus that causes acute viral encephalitis in humans. Pigs are crucial amplifier host of JEV. Recently, increasing evidences have shown that long non-coding RNAs (lncRNAs) play important roles in virus infection. Methods: The JEV proliferation was evaluated after overexpression or knockdown of lncRNA-NONSUST006715.1 using western blotting and reverse-transcription polymerase chain reaction (RT-PCR). C-C chemokine receptor type 1 (CCR1) was found to regulate the expression of lncRNA-NONSUST006715.1 by inhibitors screen. The expression of lncRNA-NONSUST006715.1 was detected using RT-PCR after overexpression or knockdown of transcription factor SP1. In addition, the enrichments of transcription factor SP1 on the promoter of lncRNA-NONSUST006715.1 were analyzed by chromatin immunoprecipitation. Results: In this study, we demonstrated that swine lncRNA-NONSUST006715.1 could suppress JEV proliferation in PK-15 cells. We also found that CCR1 inhibited the expression of lncRNA-NONSUST006715.1 via the transcription factor SP1. In addition, knockdown of CCR1 could upregulated the expression of SP1 and lncRNA-NONSUST006715.1, resulting in resistance to JEV proliferation. Conclusions: These findings illustrate the importance of lncRNAs in virus proliferation, and reveal how this virus regulates lncRNAs in host cells to promote its proliferation.