title: Domains 16 and 17 of tropoelastin in elastic fibre formation.
abstract: Naturally occurring mutations are useful in identifying domains that are important for protein function. We studied a mutation in the elastin gene, 800-3G>C, a common disease allele for SVAS (supravalvular aortic stenosis). We showed in primary skin fibroblasts from two different SVAS families that this mutation causes skipping of exons 16-17 and results in a stable mRNA. Tropoelastin lacking domains 16-17 (Delta16-17) was synthesized efficiently and secreted by transfected retinal pigment epithelium cells, but showed the deficient deposition into the extracellular matrix compared with normal as demonstrated by immunofluorescent staining and desmosine assays. Solid-phase binding assays indicated normal molecular interaction of Delta16-17 with fibrillin-1 and fibulin-5. However, self-association of Delta16-17 was diminished as shown by an elevated coacervation temperature. Moreover, negative staining electron microscopy confirmed that Delta16-17 was deficient in forming fibrillar polymers. Domain 16 has high homology with domain 30, which can form a beta-sheet structure facilitating fibre formation. Taken together, we conclude that domains 16-17 are important for self-association of tropoelastin and elastic fibre formation. This study is the first to discover that domains of elastin play an essential role in elastic fibre formation by facilitating homotypic interactions.
authors.affiliation: Department of Clinical Chemistry, Hoshi University School of Pharmacy and Pharmaceutical Sciences, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan. wachi@hoshi.ac.jp
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Wachi
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Sato
authors.forename: Junji
authors.initials: J
authors.lastname: Nakazawa
authors.forename: Risa
authors.initials: R
authors.lastname: Nonaka
authors.forename: Zoltan
authors.initials: Z
authors.lastname: Szabo
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Urban
authors.forename: Takuo
authors.initials: T
authors.lastname: Yasunaga
authors.forename: Iori
authors.initials: I
authors.lastname: Maeda
authors.forename: Koji
authors.initials: K
authors.lastname: Okamoto
authors.forename: Barry C
authors.initials: BC
authors.lastname: Starcher
authors.forename: Dean Y
authors.initials: DY
authors.lastname: Li
authors.forename: Robert P
authors.initials: RP
authors.lastname: Mecham
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Seyama
mesh_terms: D000595:Amino Acid Sequence; D021921:Aortic Stenosis, Supravalvular / Q000235:genetics / Q000378:metabolism; D004547:Elastic Tissue / Q000502:physiology*; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D005347:Fibroblasts / Q000378:metabolism; D006801:Humans; D020894:Microfibrils / Q000502:physiology; D008969:Molecular Sequence Data; D009154:Mutation; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D013696:Temperature; D014162:Transfection; D014333:Tropoelastin / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
chemical_list: D016326:Extracellular Matrix Proteins; C492373:FBLN5 protein, human; D012333:RNA, Messenger; D011994:Recombinant Proteins; D014333:Tropoelastin