title: Localization of Phosphoproteins within the Barnacle Adhesive Interface.
abstract: Barnacles permanently adhere to nearly any inert substrate using proteinaceous glue. The glue consists of at least ten major proteins, some of which have been isolated and sequenced. Questions still remain about the chemical mechanisms involved in adhesion and the potential of the glue to serve as a platform for mineralization of the calcified base plate. We tested the hypothesis that barnacle glue contains phosphoproteins, which have the potential to play a role in both adhesion and mineralization. Using a combination of phosphoprotein-specific gel staining and Western blotting with anti-phosphoserine antibody, we identified multiple phosphorylated proteins in uncured glue secretions from the barnacle Amphibalanus amphitrite The protein composition of the glue and the quantity and abundance of phosphoproteins varied distinctly among individual barnacles, possibly due to cyclical changes in the glue secretion over time. We assessed the location of the phosphoproteins within the barnacle glue layer using decalcified barnacle base plates and residual glue deposited by reattached barnacles. Phosphoproteins were found throughout the organic matrix of the base plate and within the residual glue. Staining within the residual glue appeared most intensely in regions where capillary glue ducts, which are involved in cyclical release of glue, had been laid down. Lastly, mineralization studies of glue proteins separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) indicated that proteins identified as phosphorylated possibly induce mineralization of calcium carbonate (CaCO3). These results contribute to our understanding of the protein composition of barnacle glue, and provide new insights into the potential roles of phosphoproteins in underwater bioadhesives.
authors.affiliation: Department of Oral Biology, McGowan Institute for Regenerative Medicine, University of Pittsburgh, 505 SALKP, 335 Sutherland Drive, Pittsburgh, Pennsylvania 15213; Department of Biology, The College of New Jersey, 2000 Pennington Road, Ewing, New Jersey 08628; and.
authors.forename: Gary H
authors.initials: GH
authors.lastname: Dickinson
authors.affiliation: Department of Oral Biology, McGowan Institute for Regenerative Medicine, University of Pittsburgh, 505 SALKP, 335 Sutherland Drive, Pittsburgh, Pennsylvania 15213;
authors.forename: Xu
authors.initials: X
authors.lastname: Yang
authors.affiliation: Department of Oral Biology, McGowan Institute for Regenerative Medicine, University of Pittsburgh, 505 SALKP, 335 Sutherland Drive, Pittsburgh, Pennsylvania 15213;
authors.forename: Fanghui
authors.initials: F
authors.lastname: Wu
authors.affiliation: Duke University Marine Laboratory, 135 Duke Marine Lab Road, Beaufort, North Carolina 28516.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Orihuela
authors.affiliation: Duke University Marine Laboratory, 135 Duke Marine Lab Road, Beaufort, North Carolina 28516.
authors.forename: Dan
authors.initials: D
authors.lastname: Rittschof
authors.affiliation: Department of Oral Biology, McGowan Institute for Regenerative Medicine, University of Pittsburgh, 505 SALKP, 335 Sutherland Drive, Pittsburgh, Pennsylvania 15213; ebeniash@pitt.edu.
authors.forename: Elia
authors.initials: E
authors.lastname: Beniash
mesh_terms: D000269:Adhesives / Q000737:chemistry; D000818:Animals; D015153:Blotting, Western; D002119:Calcium Carbonate / Q000378:metabolism; D010750:Phosphoproteins / Q000302:isolation & purification / Q000378:metabolism*; D001468:Thoracica / Q000378:metabolism*
chemical_list: D000269:Adhesives; D010750:Phosphoproteins; D002119:Calcium Carbonate