Figure 1.
Summary of peptides identified in NOD mouse islets and human islets by mass spectromery. Islets from (a) NOD mice or (b) non-diabetic human donors were processed and proteins were digested with either AspN or GluC, respectively. The resultant peptide mixtures were analyzed by LC-MS/MS. Data were searched against a standard proteome database then against a custom HIP database. Proteins were ranked by the number of distinct peptides identified for the protein and the top eight proteins are reported. HIPs constituted less than 2% of the total number of distinct peptides identified. MS/MS spectra matched to HIPs were later subjected to further analysis to assess the validity of each match. Numbers reported are combined totals across three independent experiments. For each NOD islet experiment, islets were harvested and pooled from a separate group of NOD mice, and each human islet sample was from a different non-diabetic donor.