Overexpression\nof ALDOC Promotes Porcine Intramuscular\nand Intermuscular Fat Deposition by Activating the AKT-mTORC1 Signaling\nPathway

Skeletal muscle fat accumulation, a common complication\nof obesity,\nhas garnered increasing attention. For livestock animals, intramuscular\nfat content is a key determinant of meat quality and directly influences\nconsumer preferences for different meat products. However, genes effectively\nregulating intramuscular and intermuscular fat (IIMF) deposition remain\nlargely unexplored. To address this gap, we employed transcriptome\nsequencing of muscle from pigs with high and low IIMF contents, uncovering\nAldolase C (ALDOC) as a novel key gene controlling IIMF. ALDOC overexpression\nsignificantly enhanced the IIMF content both in vivo and in vitro.\nMechanistic investigations revealed that ALDOC activates the AKT-mTORC1\naxis to promote lipid accumulation in myotubes and intramuscular adipocytes.\nNotably, the mTORC1 inhibitor rapamycin abrogated ALDOC’s proadipogenic\neffect. Our findings establish ALDOC as a novel key gene regulating\nIIMF deposition and identify the ALDOC-AKT-mTORC1 signaling pathway\nas a promising therapeutic target for treating skeletal muscle fat\ninfiltration and improving pork quality.