Comprehensive Analysis of the Longissimus Dorsi Transcriptome and Metabolome Reveals the Regulatory Mechanism of Different Varieties of Meat Quality.

The beef quality significantly varies between breeds. Pingliang Red Cattle resembles Wagyu in fat deposition and flavor. To screen key factors affecting beef quality, we performed meat quality trait testing, RNA-seq, and metabolomics on the longissimus dorsi of Pingliang Red Cattle, Wagyu cross F1 generation, and Simmental cattle. The gene and metabolite expression profiles were similar between Pingliang Red Cattle and Wagyu cross F1 generation. Genes such as , , , and were significantly upregulated in the Pingliang Red Cattle and Wagyu cross F1 generation ( < 0.05). Similarly, numerous metabolites, such as 3-iodo-l-tyrosine, arachidonic acid, and -aconitate, which may improve the beef quality such as fat deposition and tenderness, were found in higher levels in the Pingliang Red Cattle and Wagyu cross F1 generation. This study revealed differences in the transcriptional and metabolic levels between Pingliang Red Cattle and premium beef breeds, suggesting that Pingliang Red Cattle harbors the genetic potential for breeding high-grade beef cattle.