Isolation, Localization And Preliminary Study On The Functions Of The Porcine Gene Which Related To The Receptor HS Of PRRSV

As diseases cause huge economic damage in livestock, it restricts the rapid development of the pig industry. The research in breeding for disease resistance plays an important role in pig industry. PRRS which called "high-fever" outbroke in more than 10 provinces of china. This epidemic brought about impact on about 2.12 million pigs and caused the death of at least 40 million pigs. PRRS has been the most serious infectious disease which has restricted the healthy development of pig industry.PRRSV enters host cells mediated by receptors. Four receptors (HS, SN, CD151 and CD 163) have been identified at present. HS plays a role in virus adhesion, it can fix the free virus on cell surface. The enzyme which called NDST4(N-deacetylase/N-sulfotransferase-4) and HPSE(heparanase) played important role in metabolic process of HS. So we study the receptor of PRRSV (HS) which plays a role of attachment process in this research. Here, we chose the porcine genes which related to the receptor of PRRSV (HS) to do further investigation. The results which we achieved are as follows:1. Porcine SDC2 and HPSE were isolated and identified by comparative genomics and bioinformatics.With the corresponding software to analyzing the coding regions of these two genes, we deduced the amino acid sequence of these two genes and 4.1m domain on SDC2 (putative band 4.1 homologues’ binding motif)2. The SDC2, PERLECAN and HPSE were precisely located to Sscr4, Sscr 6 and Sscr8, and closed to SW362, SW709 and SW1980 by IMpRH panel.3. We used the PT-PCR to analysis the tissue expression pattern of the three genes. The results revealed that SDC2 was high expression in all tissues but liver. PERLECAN was expressed in all tissues except lymph. HPSE was only expressed in liver, lung and small intestine.4. Some differential expression genes were screened from microarray, including porcine HPSE and NDST4 genes. The results of microarray were verificated by QPCR.5. We used the PCR-RFLP and PCR sequencing to scan SNPs and make the association analysis with immune traits. In the experimental population of Huangpi, the results showed that BanⅡpolymorphism in 5’UTR of SDC2 was associated with MCV and HGB. HpyCH4Ⅳpolymorphism in exon 3 of SDC2 was associated with RBC and HCT. Sau96 I polymorphism in 3’UTR of PERLECAN was associated with MCH. Alu I polymorphism in exon 5 of HPSE was associated with RBC, WBC, HGB and HCT.These results can provide the basis for the disease resistance of PRRSV between different species and material for candidate gene of pig breeding for disease resistance.