Early differential gene expression in beef Longissimus thoracis muscles from carcasses with normal ( 5.9) ultimate pH

Abstract The objective of this study was to investigate early postmortem (0.5 h) gene expression in beef Longissimus thoracis (LT) muscles from carcasses with NORMAL ( 5.9) ultimate pH (pH u ). A total of 53 transcripts were differentially expressed ( P -value u carcasses. Four up-regulated ( PDK4, GADD45B, MAOA, METTL21C ) genes were confirmed ( P u samples resulted with lower values in glycolytic potential and AMP-activated protein kinase activity compared to NORMAL at 0.5 and 24 h postmortem (P  GADD45B, METTL21C and MAOA were overexpressed. These genes are involved in stress signaling that might be affecting Ca 2+ transport and oxidative metabolism pathways in HIGH pH muscles.