| Dabry’s sturgeon(Acipenser dabryanus)is a national level I extremely endangered animal.In recent years,although the artificial breeding of Dabry’s sturgeon has achieved great success in farming,it has caused great losses due to diseases every year.Therefore,immune control has become an important entry point to solve this problem.Based on the information about the transcriptome of Dabry’s sturgeon,this study selected six genes in the interferon signaling pathways,such as SIGIRR(Single Ig IL-1R–related molecule),TRAF6(Tumor necrosis factor receptor-associated factor 6),Mx(Myxovirus resistance),Viperin(virus inhibitory protein,endoplasmic reticulum-associated,interferon-inducible),PKR(Double-stranded RNA-dependent protein kinase)and ADAR(Adenosine deaminase acting on RNA).In this study,we cloned the cDNA and DNA sequences of SIGIRR,TRAF6,Mx,Viperin,PKR and three ADAR subtypes(ADAR1-1,ADAR1-2 and ADAR4),respectively,and detected these by qPCR.The expression pattern of the gene in the tissue and the expression change after induction by Poly(I:C)(polyinosinic-polycytidylic acid).All results are as follows:The ORF lengths of the SIGIRR and TRAF6 genes of Dabry’s sturgeon were 1641 bp and 1668 bp,respectively,encoding 546 and 555 amino acids,respectively.The predicted SIGIRR protein has a molecular weight of about 58.86 KDa;a theoretical isoelectric point of 5.09;and an instability index of 46.64,which is an unstable protein.The protein molecular weight of TRAF6 is 62.54 KDa;the theoretical isoelectric point is 5.64;the instability index is 61.60,which is also unstable protein.The SIGIRR and TRAF6 proteins in Dabry’s sturgeon are similar in similarity and identity to the corpus callosum(Acipenser ruthenus),with similarities of 97.70% and 98.37%,respectively.The protein structure of SIGIRR in Dabry’s sturgeon has two Ig structures and one TIR domain,which is very consistent with the homologous gene protein domain of the small body,while TRAF6 is highly consistent with the homologous protein domain of other species.In addition,the SIGIRR gene of Dabry’s sturgeon contains 9 exons and 8introns,and there are 4 exons of the same size between different species,while TRAF6 contains 3 exons and 2 introns.SIGIRR and TRAF6 were expressed in all tissues examined,with SIGIRR having the highest expression in the intestine and lowest expression in the blood;TRAF6 was highest in the head kidney,followed by the intestine,which was the lowest in the blood.After using Poly(I:C)to simulate infection of Dabry’s sturgeon scorpion fin cells,the expression of SIGIRR in Dabry’s sturgeonwas significantly down-regulated at 3 h(P<0.01),and returned to normal level at 6 h;the TRAF6 in Changjiang was 6 h.Significantly up-regulated by 24 h.These results indicate that SIGIRR and TRAF6 may play an important role in the TLR signaling pathway induced by scorpion virus.Dabry’s sturgeon Mx gene sequence contains a 1449 bp long ORF encoding 392 amino acids,and a 123 bp 5’ untranslated region(UTR)and an incompletely sequenced3’.The ORFs of the Viperin and PKR genes are 1050 bp and 1221 bp,respectively,encoding 349 and 406 amino acids,respectively.Although the similarity and identity between Mx and other animal Mx proteins are very low,Yangtze River Mx contains conserved triple GTP binding motifs and dynamin family features.The similarity and identity of the proteins and the multiple comparisons of the sequences indicate that the Viperin and PKR are relatively conserved in species.In addition,Dabry’s sturgeon Mx gene has 8 exons and 7 and introns;Viperin contains 6 exons and 5 introns,while PKR has 13 exons and 12 introns.The expression of Mx,Viperin,PKR and ADAR was detected in all tissues examined,and was mainly expressed in skin,blood,brain,and intestines and skin,respectively.After using Poly(I:C)to simulate infection of Dabry’s sturgeon skeletal fin cells,Mx,Viperin and PKR were significantly up-regulated from 6h to 24 h(P<0.05),and ADARs also changed significantly.These results suggest that Dabry’s sturgeon Mx,Viperin,PKR and ADAR may play important antiviral effects in the innate immune system of Dabry’s sturgeon. |
