The genes from the tissue-specific proteoforms identified in this study were tied to the core function of the tissues as broadly indicated by GEO analysis. This is further supported by specific examples such as proteins that regulate muscle contractility (PLN, RLCV, cardiac troponins), hostpathogen interaction (defensins), cytoskeletal reorganization (CRMP-2), and metabolic detoxification (family of glutathione transferases). In many cases, these unique proteoforms were regulatory light chain; RPLC, reversed phase liquid chromatography; SERCA, sarcoplasmic reticulum calcium pump; SNP, single nucleotide polymorphism; TDMS, top-down mass spectrometry; TDP, top-down proteomics; TMC, tissue mapping center. identified phosphorylation of cardiac troponin I as a candidate biomarker for chronic heart failure. J Proteome Res 2011, 10 (9), 4054-65. .