Cloning, Expression Analysis And MicroRNA Study Of Horn Trait Candidate Genes In Yak

Polled yaks are easy to be managed, and also can avoid the economic loss due to accidental injuries. However, the molecular mechanism of polled trait of yak is still unclear. We choose polled yak and horned yak for the study, using molecular biology techniques to clone horn trait candidate genes of yak, and analyze the difference expression of candidate genes and its MicroRNA, in order to filter out major genes of affecting polled trait of yak, provide some theoretical basis for breeding of polled yaks. We had got this results as follows:Firstly, the CDS of yak C1H21orf62, RXFP2 and OLIG2 gene were cloned. The length CDS of C1H21orf62 was 510 bp, encoding 161 amino acids. The C1H21orf62 protein is a hydrophilic protein, containing 13 potential phosphorylation sites, no transmembrane domains and signal peptide. The length CDS of RXFP2 was 2213 bp, encoding 737 amino acids. RXFP2 is a hydrophobic protein, containing 28 potential phosphorylation sites, signal peptide was located 1-21 amino acid of RXFP2 protein, no transmembrane domain. The length CDS of OLIG2 was 651 bp, encoding 216 amino acids. OLIG2 is a hydrophilic protein, containing 29 potential phosphorylation sites, no transmembrane domains and signal peptide.Secondly, analysis expression of 6 horn trait candidate genes of yak by Real-time quantitative PCR method, results show that there were no significant difference for the relative mRNA expression of SYNJ1, FOXL2 and GCFC1 genes between polled yak and horned yak horn buds tissue. C1H21orf62 relative mRNA expression of polled horn bud individual was significantly higher than individuals with horned horn bud. RXFP2 gene relative mRNA expression of polled horn bud individuals was higher than the individuals with horned horn bud, the results show that the transcription abundance of C1H21orf62, RXFP2 gene was associated with polled trait of yak. OLIG2 gene was only expressed in the individuals with polled horn bud, and no expression in the individuals with horned horn bud, it was implied that polled trait of yak was associated with mRNA expression of OLIG2 gene.Thirdly, through the software predict target MicroRNA of yak OLIG2 gene: bta-miR-302 b, bta-miR-302 c and bta-miR-302 d, Real-time quantitative PCR method was applied to analyze the their expression, the results show that bta-miR-302 b, bta-miR-302 c and bta-miR-302 d were expressed in horn buds of the polled yak and horned yak, but not significantly. It was supposed that the regulation of expression of OLIG2 gene in yak horn buds may not be affected by bta-miR-302 b, bta-miR-302 c and bta-miR-302 d.