Research On MC1R And TYR Gene Sequence And MRNA Expression Of Bian Chicken

Melanocortin1receptor (MC1R), also called Melanocyte-stimulating hormone receptor (MSHR) gene, is encoded by extension locus, and it is an important gene to control animal melanin synthesis. Tyrosinase is rate-limiting enzyme during the process of melanin synthesis, and the only product of tyrosinase gene expression. Its expression and activity determine the melanin production speed and yield.1. MC1R gene is an important gene to control animal melanin synthesis. The experiment chooses MC1R gene as the candidate gene for controlling Chicken melanin synthesis, takes Bian chickens reared by Shanxi Agricultural University as the research object. According to relevant expert and his colleagues’ report, based the complete sequence of Chicken’s MC1R gene, it designs a pair of primer PB. The amplification conditions of this gene fragment PCR were optimized, hence to obtain the corresponding product. Through the application of the bioinformatics knowledge, such as BLAST, SWISS-MODEL, SCOP and CSD, it compares Bian Chicken’s MC1R gene sequence with that of the original chicken. The results shows that the sequence homology of Bian chicken and original chicken is up to99.11%. Finally, by analyzing the sequencing results with the homology of other animals, it obtains the dendrogram. And through the analysis of its amino acid sequence, secondary and tertiary structure are predicted.2. TYR gene is the major gene which controls chicken melanin synthesis. Its encoded tyrosinase plays a key role in the process of melanin synthesis. The experiment takes Bian chickens reared by Shanxi Agricultural University as the research object. Based on the chicken TYRmRNA sequence from NCBI to design primer and extract total RNA from Bian chicken’s feather pulp, after reverse transcription, it obtains cDNA as a template. PCR products were cloned and sequenced, and acquires partial cDNA gene sequence of Bian chicken TYR gene, and then compares with TYR cDNA sequence of the original chicken. The results indicate that partial cDNA sequence of Bian chicken TYR gene has a high degree of homology with the original chicken.3. By using real-time quantitative PCR research on the developmental changes of the MC1R gene mRNA expression in feather pulp, skin and liver tissue of black and greyish-white Bian chicken which are at the same days of age, nutritional status and growth conditions. The results indicate that there is a significant difference (P<0.01) in the expression level of MCIR gene and TYR gene mRNA of black Bian chicken and greyish-white Bian chicken. The expression level of black chicken is significantly higher than the greyish-white chicken. The expression level of MCIR gene and TYR gene mRNA in the feather pulp of black Bian chicken is significantly higher than that of greyish-white Bian chicken (P<0.05). There is no significant difference in the expression level of MCIR gene and TYR gene mRNA in the liver tissue of black and greyish-white Bian chicken (P>0.05)...