Analysis of Histatin 5 salivary complexes by using mass spectrometry

Abstract

Background: With recent progress in the analysis of the salivary proteome, the number of salivary proteins identified has increased dramatically. However, the physiological functions of many of the newly discovered proteins remain unclear. Closely related to the study of a protein's function is the identification of its interaction partners. Although in saliva some proteins may act primarily as single monomeric units, a significant percentage of all salivary proteins, if not the majority, appear to act in complexes with partners to execute their diverse functions.Hypothesis: We hypothesize that interactions among salivary proteins protect complex partners from proteolysis, modulate their biological activities and serve as delivery systems for the distribution of secretory salivary proteins throughout the oral cavity.Objective: The aim of this study will be to identify the heterotypic complexes between histatin 5 (a potent natural antifungal protein) and other salivary proteins in saliva by using classical protein-protein interaction methods in combination with high-throughput mass spectrometric techniques analysis, and to explore the biological roles of these new salivary complexes.Significance: The results of the work proposed herein will contribute significantly to characterization of the salivary complex of vertebrates, and to understanding the biology of salivary protein complex. This study will be the first to identify histatin 5 protein complexes by using mass spectrometry. (AU)