Proteome wide determination of absolute turnover rates in mice

Abstract

The administration of labeled amino acids has become the preferred method to measure the dynamics of protein turnover in living animals. Stable isotopes have been used as tracers to explore the amino acid flux in different metabolic pathways. Recently, the stable isotope labeling of amino acids in cell culture (SILAC), has been used to monitor individual protein turnover rates in cell culture and intact animals. This method is based on the incorporation of labeled essential amino acids resulting in appearance of labeled end products that can be quantified by mass spectrometry. We have performed an pulsed SILAC labeling of mice to calculate the protein turnover via the incorporation rate of labeled amino acid in post mitotic cardiomyocytes and could easily be applied to tissue from Lung.