biostudies-literatureUnknown9(10)de Sousa-Pereira PCystatins are a family of inhibitors of cysteine peptidases that comprises the salivary cystatins (D and S-type cystatins) and cystatin C. These cystatins are encoded by a multigene family (CST3, CST5, CST4, CST1 and CST2) organized in tandem in the human genome. Their presence and functional importance in human saliva has been reported, however the distribution of these proteins in other mammals is still unclear. Here, we performed a proteomic analysis of the saliva of several mammals and studied the evolution of this multigene family. The proteomic analysis detected S-type cystatins (S, SA, and SN) in human saliva and cystatin D in rat saliva. The evolutionary analysis showed that the cystatin C encoding gene is present in species of the most representative mammalian groups, i.e. ArtiodaPloS onee109050https://www.ebi.ac.uk/biostudies/studies/S-EPMC4201479biostudies-literatureEvolution of C, D and S-type cystatins in mammals: an extensive gene duplication in primates.PMC4201479Pinheiro AEsteves PJVitorino Rde Sousa-Pereira PColaco BAbrantes JfalseEvolution of C, D and S-type cystatins in mammals: an extensive gene duplication in primates.Cystatins are a family of inhibitors of cysteine peptidases that comprises the salivary cystatins (D and S-type cystatins) and cystatin C. These cystatins are encoded by a multigene family (CST3, CST5, CST4, CST1 and CST2) organized in tandem in the human genome. Their presence and functional importance in human saliva has been reported, however the distribution of these proteins in other mammals is still unclear. Here, we performed a proteomic analysis of the saliva of several mammals and studied the evolution of this multigene family. The proteomic analysis detected S-type cystatins (S, SA, and SN) in human saliva and cystatin D in rat saliva. The evolutionary analysis showed that the cystatin C encoding gene is present in species of the most representative mammalian groups, i.e. Artioda2014-01-01T00:00:00Z20142026-05-02T17:25:59.08Z2019-03-26T23:21:52ZS-EPMC42014792532971710.1371/journal.pone.0109050