For all enzymatic digestion data,autolytic tryptic products, keratin and blank artifacts were assigned and removed before database search (SWISSPROT,December 2013) using Mascot with the following parameters:taxonomy Homo sapiens, monoisotopic mass values,peptide mass tolerance of ±0.3 Da (for PMF and PSD experiments),2 missed cleavages,afixed modification carboxyamidomethylation and methionine oxidations set as variable modification.