Relationships between Pectoralis Muscle Proteomes and Shear Force in Thai Indigenous Chicken Meat

Abstract

Two-dimensional gel electrophoresis and matrix-assisted laser desorption ionization time-offlight mass spectrometry (MALDI-TOF/MS) were used to investigate the association of pectoralis muscle proteomes with Warner-Bratzler shear force (WBSF) values in Thai indigenous chicken meat. A total of 169 proteome spots were found in chicken muscle. Of these, three protein spots were significantly upregulated and associated with high-WBSF values. These protein spots were characterized and showed homology with pyruvate kinase (PKM2), phosphoglycerate mutase1 (PGAM1) and triosephosphate isomerase1 (TPI1). Moreover, the protein expression levels were highly correlated to the WBSF values. The PKM2 and TPI1 proteins were positively correlated to the WBSF values (r=0.71, p<0.05 and r=0.65, p<0.05, respectively), whereas, the PGAM1 protein trended toward an association with the WBSF values (r=0.49, p=0.15). Additionally, the expression levels of PGAM1 were positively correlated to the TPI1 protein expression levels (r=0.88, p<0.01), whereas no significant correlation between the expression levels of PKM2 and PGAM1 (r=0.43, p=0.21) and PKM2 and TPI1 were found (r=0.51, p=0.13). The results indicated that these three proteomes of the glycolytic pathway are important in the energy
metabolism processes of muscle. This finding promotes PKM2, PGAM1 and TPI1 as the functional protein markers for the tenderness trait in Thai indigenous chicken.