Abstract
The lean-to-fat ratio is a major issue in the beef meat industry from both carcass and meat production perspectives. This industrial perspective has motivated meat physiologists to use transcriptomics technologies to decipher mechanisms behind fat deposition within muscle during the time course of muscle growth. However, synthetic biological information from this volume of data remains to be produced to identify mechanisms found in various breeds and rearing practices. We conducted a meta-analysis on 10 transcriptomic data sets stored in public databases, from the longissimus thoracis of five different bovine breeds divergent by age. We updated gene identifiers on the last version of the bovine genome (UCD1.2), and the 715 genes common to the 10 studies were subjected to the meta-analysis. Of the 238 genes differentially expressed (DEG), we identified a transcriptional signature of the dynamic regulation of glycolytic and oxidative metabolisms that agrees with a known shift between those two pathways from the animal puberty. We proposed some master genes of the myogenesis, namely MYOG and MAPK14, as probable regulators of the glycolytic and oxidative metabolisms. We also identified overexpressed genes related to lipid metabolism (APOE, LDLR, MXRA8, and HSP90AA1) that may contribute to the expected enhanced marbling as age increases. Lastly, we proposed a transcriptional signature related to the induction (YBX1) or repression (MAPK14, YWAH, ERBB2) of the commitment of myogenic progenitors into the adipogenic lineage. The relationships between the abundance of the identified mRNA and marbling values remain to be analyzed in a marbling biomarkers discovery perspectives.
Highlights
The management of muscle mass and/or of meat-eating qualities requires a good understanding of the molecular drivers of muscle growth and composition
We identified overexpressed genes related to lipid metabolism (APOE, low-density lipoprotein receptor (LDLR), MXRA8, and HSP90AA1) that may contribute to the expected enhanced marbling as age increases
We considered 125 bovines from Angus, Belmont Red, Chinese Red Steppe pure breeds, as well as from Piedmontese ϫ Hereford and Wagyu ϫ Hereford crossbreds over the time course of longissimus thoracis muscle growth, i.e., from 31 to 732 days of postnatal life (Table 1)
Summary
The management of muscle mass and/or of meat-eating qualities requires a good understanding of the molecular drivers of muscle growth and composition. Aging, the most influential nongenetic factor, decreases muscular fiber and increases intramuscular adipose and connective tissues proportions [9, 26, 41, 48] These age-related muscular composition variations affect sensorial and nutritional meat-eating qualities [41]. This has motivated the age-dependent high-throughput molecular characterization of bovine muscle [4, 14, 30, 33, 43, 50, 55, 57, 72]. This is the first attempt to reuse public bovine muscular transcriptomic data to identify conserved patterns between breeds and rearing practices and to propose potential indicators of muscular growth and composition in bovine
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
