The Effect of Protein Abundance in Porcine Skeletal Muscle on the Expression of Water Holding Capacity

Water holding capacity measured as drip loss is the ability of the skeletal muscle to retain water post-mortem. The aim of this work was a global proteome analysis in order to identify the relevant biological mechanism of porcine muscle proteins, with potential functional relevance for drip loss. For this experiment a Duroc x Pietrain F₂ resource population (n = 42) was used. Proteins were isolated from the Musculus longissimus dorsi of the F₂ animals. The relative protein quantification was performed using isotope-coded protein labeling techniques and electrospray ionization liquid-chromatography-tandem mass spectrometry. In total, 763 different proteins were identified. The proteins, PYGL, PYGM, HSPA8, EE1A1, ACTA1, CASQ1, FLN-C, MYOM1, TNNT3,  and HSP27 were up regulated and TNNI1, MYL3, MYL2, MB, MYBPC1, FHL1C, TPM1, TPM2, AK1, TNNC2, MYL11, CK, PGK1 and MYH7were down-regulated comparing animals with low and high drip loss. Results revealed that the high drip loss meat was characterized  by higher level of glycolytic enzymes than in low drip loss meat. Additionally, we could observe that higher levels of chaperone proteins were associated with a low drip loss level.