Quantification of biomarkers for beef meat qualities using a combination of Parallel Reaction Monitoring- and antibody-based proteomics.

We and others have identified biomarker candidates of tenderness or marbling, two major attributes of bovine meat-eating qualities for consumers' satisfaction. In this study, Reverse Phase Protein Arrays (RPPA) and targeted mass spectrometry assays using Parallel Reaction Monitoring (PRM) were developed to test whether 10 proteins pass the sequential qualification and verification steps of the challenging biomarker discovery pipeline. At least MYH1, TPI1, ALDH1A1 and CRYAB were qualified by RPPA or PRM as being differentially abundant according to marbling values of longissimus thoracis and semimembranosus muscles. Significant mathematical relationships between the individual abundance of each of the four proteins and marbling values were verified by linear or logistic regressions. Four proteins, TNNT1, MDH1, PRDX6 and ENO3 were qualified and verified for tenderness, and the abundance of MDH1 explained 49% of the tenderness variability. The present PRM and RPPA results pave the way for development of useful meat industrial multiplex-proteins assays.