Updated project metadata. We used LC-MS/MS based proteomics to identify changes in protein expression in the the female and male mouse hippocampus at 1, 2, and 4 months of age. This proteomics dataset was correlated with an accompanying mRNA dataset to identify genes that show mRNA changes in a different direction that their respective proteins. A modest correlation was found between mRNA and protein abundance in the mouse hippocampus (spearman rank coefficient = 0.53).