Assessment of RNAlater as a Potential Method to Preserve Bovine Muscle Proteins Compared with Dry Ice in a Proteomic Study.

RNAlater is regarded as a potential preservation method for proteins, while its effect on bovine muscle proteins has rarely been evaluated. Bovine muscle protein samples ( = 12) collected from three tender (Warner⁻Bratzler shear force: 30.02⁻31.74 N) and three tough (Warner⁻Bratzler shear force: 54.12⁻66.25 N) Longissimus thoracis et lumborum (LTL) samples, preserved using two different sampling preservation methods (RNAlater and dry ice), at two time points (day 0 and day 14), were characterized using one-dimensional electrophoresis. Fourteen bands with molecular weights ranging from 15 to 250 kDa were verified, both in the dry ice and RNAlater storage groups, at each time point, using image analysis. A shift from high to low molecular weight fragments, between day 0 and day 14, indicated proteolysis of the muscle proteins during post mortem storage. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analyses and database searching resulted in the identification of 10 proteins in four bands. Protein profiles of muscle preserved in RNAlater were similar to those of muscle frozen on dry ice storage, both at day 0 and day 14. The results demonstrate that RNAlater could be a simple and efficient way to preserve bovine muscle proteins for bovine muscle proteomic studies.