MiR-330-5p negatively regulates ovine preadipocyte differentiation by targeting branched-chain aminotransferase 2.

The differentiation of preadipocytes into adipose tissues is tightly regulated by various factors including microRNAs and cytokines. This article aims to study the effect of miR-330-5p on expression of BCAT2 in ovine preadipocytes. Ovine preadipocytes were isolated, and we found that the miR-330-5p expression decreased gradually during the early differentiation of ovine preadipocytes, while BCAT2 expression increased. BCAT2 was identified as a direct target of miR-330-5p, ectopic expression of miR-330-5p could change the expression of both BCAT2 mRNA and protein. Silencing BCAT2 had the same inhibition effects as overexpressing miR-330-5p on the preadipocyte differentiation, but overexpressing BCAT2 had the converse effects. Taken together, we demonstrated that miR-330-5p is a negative regulator of differentiation by targeting BCAT2, and clarified the role of BCAT2 and miR-330-5p during preadipocyte differentiation.

Relative abundance of G protein-coupled receptor 30 and localization in testis and epididymis of sheep at different developmental stages.

The G protein-coupled receptor 30 (GPR30) is a transmembrane estrogen receptor that binds to estrogen, and has been confirmed to have an important role in testicular cell proliferation and development. The main objective of this study was to examine GPR30 gene expression and localization in the testis and epididymis of sheep at different developmental stages. Testes, including the epididymis, were collected from Polled Dorset x Mongolian cross rams at one (n=4; wt), three (n=4; wt), six (n=4; wt), nine (n=4; wt) and 12 (n=4; wt) months of age. The 12-month-old hybrid crossbred sheep were exsanguinated via puncture of the jugular vein. Relative abundance of GPR30 mRNA was detected by quantitative PCR, and localization of the protein was examined by immunohistochemistry. Semi-quantitative analysis of GPR30 protein was performed by western blotting. The relative abundance of GPR30 mRNA was similar in the epididymis tail for rams at 6, 9, and 12mo of age. Further, relative abundance of GPR30 mRNA in the testes and caput epididymis of 1-, 3-, 6-, 9-, and 12-month-old crossbred rams did not increase with age. The GPR30 mRNA was detected in epididymal interstitial and principal cells, and in the epididymal cavity, spermatocytes, spermatogonial stem cells, Sertoli and Leydig cells, and spermatozoon of ram testes. Western blotting indicated the GPR30 protein was present in 9- and 12-month-old crossbred sheep corpus, cauda epididymis (P<0.05). The results suggest that relative abundance of GPR30 mRNA is time-dependent and localization-specific.

Polymorphisms in chicken extracellular fatty acid binding protein gene.

In this study, we report the investigation of extracellular fatty acid binding protein gene (Ex-FABP) genetic polymorphism in a sample of 360 chicken individuals. The screening of the coding regions with their intron-exon boundaries and the proximal flanking regions was performed through a PCR-SSCP strategy. Following sequence analysis revealed 35 novel single nucleotide polymorphisms (SNPs) of chicken Ex-FABP gene. Among the 35 SNPs, twenty-five were found in the introns. And the remaining seven and three SNPs were in the coding region and the 5'UTR, respectively. Two SNPs in the coding region caused two missense mutants and the other five did not result in any amino acid changes. The nature and the distribution of Ex-FABP mutations in three chicken breeds were analyzed. Variations detected here might have an impact on Ex-FABP activity and function and underpin the development of gene markers for chicken fatty deposition and metabolism. The polymorphism, generated by C4715T mutation in exon5, was significantly associated with thickness of subcutaneous fat plus skin in cocks. Subcutaneous fat plus skin of cocks was more thick in TT genotype than in CC genotype (P < 0.05). The Ex-FABP gene could be a candidate locus or linked to a QTL that significantly affects fatty deposition and metabolism in chicken.