title: Specificity in the coacervation of tropoelastin: solvent exposed lysines.
abstract: Tropoelastin protein monomers associate by coacervation and are cross-linked in vivo to form elastin macro-assemblies. We provide evidence for specific protein domain contact points between tropoelastin monomers during association by coacervation. The homobifunctional cross-linker bis(sulfosuccinimidyl) suberate served as a rapid reporter of adjacent lysines and preferentially exposed domains. Intact cross-linked peptide pairs were identified after protease digestion and high-resolution electrospray mass spectrometry followed by MS/MS sequencing. Mapping of the assigned sequences indicated that the region in the monomer spanning domains 19-25 was readily accessible to solvent and enriched in cross-linking. Domains 12 and 36 were also prevalent, where these two regions were not previously thought to play a major role in the formation of mature elastin. A specificity for particular lysines allowed for the construction of a model for the first close contacts between domains and the first detailed study of the cross-linking of tropoelastin.
authors.affiliation: School of Molecular and Microbial Biosciences, University of Sydney, NSW 2006, Australia.
authors.forename: Steven G
authors.initials: SG
authors.lastname: Wise
authors.forename: Suzanne M
authors.initials: SM
authors.lastname: Mithieux
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Raftery
authors.forename: Anthony S
authors.initials: AS
authors.lastname: Weiss
mesh_terms: D000595:Amino Acid Sequence; D003432:Cross-Linking Reagents / Q000737:chemistry; D006801:Humans; D008239:Lysine / Q000737:chemistry*; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D015394:Molecular Structure; D020836:Protein Structure, Quaternary; D012997:Solvents / Q000737:chemistry*; D013388:Succinimides / Q000737:chemistry; D014333:Tropoelastin / Q000737:chemistry* / Q000235:genetics
chemical_list: D003432:Cross-Linking Reagents; D012997:Solvents; D013388:Succinimides; D014333:Tropoelastin; C035760:bis(sulfosuccinimidyl)suberate; D008239:Lysine