Chronological Expression of and Genes and the Association between Their Polymorphisms and Chicken Meat Quality Traits.

Meat quality is closely related to the development of skeletal muscle, in which and genes play important regulatory roles. The present study firstly provided the data of chronological expression files of and genes in the post-hatching pectoral muscle and analyzed the association of their polymorphisms with the meat quality traits of Wuliang Mountain Black-bone (WLMB) chickens. The results showed that both and genes were weakly expressed in the second and third weeks, and then increased significantly from the third week to the fourth week. Furthermore, there was a significant positive correlation between the expression levels of the two genes. Twelve and one SNPs were detected in the chicken and genes, respectively, of which four SNPs (g.9830C > T, g.10073C > T, g.13335G > A, g.13726A > G) of the gene and one SNP (g.564G > A) of the gene were significantly associated with chicken meat quality traits. For the gene, chickens with the CT genotype of g.9830C > T showed the highest meat color L*, shear force (SF), pH, and the lowest electrical conductivity (EC), and drip loss (DL) ( < 0.05 or < 0.01); chickens with the CC genotype of g.10073C > T had the lowest L*, pH, and the highest DL ( < 0.01). For the SIX1 gene, chickens with the GG genotype of g.564G > A had the highest ( < 0.05) SF and pH. Furthermore, pH had a significant correlation with all the other meat quality traits. The current study could contribute to the research of regulatory mechanisms of meat quality and lay the foundation for improving meat quality based on marker-assisted selection in chickens.