| The quest for effective strategies to treat obesity has propelled fat research into an exploration of the molecular processes that inhibit the expression of lipogenetic genes, so the identification of the relevant genes has become the premise. Oxidized low-density lipoprotein receptor 1 (OLR1) belongs to the C-type lectin family and shows its binding activity to multiple ligands indicating that OLR1 has complicated biological functions. In preadipocytes, the expression of OLR1 is concerned with absorption of fatty acid and cholesterol transport. At present, studying on the lipid metabolism role of OLR1 is still on at primary stage, especially, it is not found about the reports on the role of OLR1 in porcine adipose tissue. So our experiment took the cloning of OLR1 coding sequence in porcine adipose tissue as the first step, then gave an approach to sequence feature, expression profile, function pathway and the possible function mechanism from molecular biology, cell biology as well as bioinformatics. The main results were summarized as following:1. OLR1 in porcine adipose tissue expanded a lenth of 825 bp, coding 273 amino acids. OLR1 gene in pig adipose tissue exhibits 99% homology to that in pig aortic endothelial tissue and the homology to cattle, human, rat and mouse were: 84%,79%,51%,27%, respectively. The OLR1 protein has one transmembrane helices structure, which belongs to 2 type membrane protein. The signal peptide located from amino acid 38 to 60 and the domain from amino acid 144 to 256 was shared by C-type lectin family.2. Genes including OLR1in mammals C-type lectin family had a high content of A+U (61.2%), which was extremely higher than that of G+C (38.8%), and moreover, A- and U-ending codons were preferentially used(accounting for 76.53%). The codons AGA, AGG, GCU etc. were preferred used while UGG, CCG, CGC were sedomly used. Gene heterogeneity analysis indicated that most members in this family clustered together as one category.3. OLR1 mRNA showed its higher expression in subcutaneous adipose tissue than visceral adipose tissue. And moreover, the expression level of OLR1 mRNA increased significantly in pig adipose tissue with development (P < 0.01) and in the same MA, the expression level of OLR1 mRNA in obesity-type pig was significantly higher than that of lean-type pig (P < 0.05). In adipose tissue, the expression of OLR1 correlates with peroxisome proliferator-activated receptorγ2 (PPARγ2), fatty acid synthetase (FAS) and Sterol Regulatory Element Binding Protein-1c (SREBP-1c), but not Triacylglycerol hydrolase (TGH) and CAAT/enhancer binding proteinα(C/EBPα).4. In the differentiation process of mouse preadipocytes, OLR1 mRNA expression level in short chain fatty acid (SCFA) treated group was significant lower than control group while OLR1 mRNA expression level in short chain fatty acid (LCFA) treated group was significant higher than control group. After treat with P38MAPK inhibitor, OLR1 mRNA expression level in SCFA treated group was significant lower than that of without treat, while OLR1 mRNA expression level in LCFA treated group was significant lower than that of control group.5. In the differentiation process of mouse preadipocytes, the cell number in SCFA group was time-depend decreased significantly (p<0.05) while the cell number in LCFA treated group and control group had no significant change. PPARγ2, C/EBPα, FAS, SREBP-1c mRNA expression level were all significantly higher than control group(p<0.05), while the TGH mRNA expression level did not change; in the presence of PC8MAPK inhibitor, PPARγ2, FAS, SREBP-1c mRNA expression level were all significantly lower than control group(p<0.05) while C/EBPαand TGH had no significant change.
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