Updated project metadata. The mouse liver mitochondrial proteome was analysed in four different mouse groups (allocation of the samples to Exp1 and Exp2 in brackets): AL (ad libitum fed) C57Bl6 (Exp1 129, Exp1 130, Exp2 130), DR (dietary restriction) C57Bl6 (Exp1 126, Exp1 127, Exp1 128), AL ICRFa (Exp2 128, Exp2 129) and old ICRFa (Exp2 126, Exp2 127). To achieve quantitative standardisation between Exp1 and Exp2, all 10 samples were pooled and one portion of the pool was anlaysed in each Exp (Exp1 131 and Exp2 131). Following tryptic digest and TMT 6-plex labelling, samples were separated by OffGel electrophoresis and all fractions were subsequently analysed by LCMSMS on an Orbitrap LTQ XL. One survey scan (res. 30,000) was followed by a high energy HCD scan (res. 6000) and a low energy CID scan in the LTQ. HCD data were used for the quantitation and CID data for the identification of peptides. Data were searched using Mascot (v. 2.2) through the Proteome Discoverer interface. Peptide raw quantitations were extracted as text files and further processed using dpeaqms (http://r-forge.r-project.org/projects/dpeaqms/) to obtain probability values for the differences in protein amounts for specific proteins between the different animal groups.