title: Characterization of green alga, yeast, and human centrins. Specific subdomain features determine functional diversity.
abstract: Centrins are a subfamily within the superfamily of Ca2+-modulated proteins that play a fundamental role in centrosome duplication and contraction of centrin-based fiber systems. We examined the individual molecular properties of yeast, green alga, and human centrins. Circular dichroism spectroscopy revealed a divergent influence of Ca2+ binding on the alpha-helical content of these proteins. Ca2+-free centrins were elongated in shape as determined by size exclusion chromatography. The presence of Ca2+ and binding peptide resulted in more spherical shaped centrins. In contrast to yeast calmodulin, centrins formed multimers in the Ca2+-bound state. This oligomerization was significantly reduced in the absence of Ca2+ and in the presence of binding peptide. The Ca2+-dependent polymerization of the green alga Scherffelia dubia centrin (SdCen) resulted in a filamentous network. This molecular property was mainly dependent on the amino-terminal subdomain and the peptide-binding site of SdCen. Finally, we analyzed whether SdCen and Cdc31p-SdCen hybrid proteins functionally substitute for the Saccharomyces cerevisiae centrin Cdc31p. Only hybrid proteins containing the amino-terminal subdomain or the third EF-hand of SdCen and the other subdomains from Cdc31p were functional in vivo.
authors.affiliation: Max-Planck-Institut für Biochemie, Genzentrum, Am Klopferspitz 18a, 82152 Martinsried, Federal Republic of Germany.
authors.forename: H
authors.initials: H
authors.lastname: Wiech
authors.forename: B M
authors.initials: BM
authors.lastname: Geier
authors.forename: T
authors.initials: T
authors.lastname: Paschke
authors.forename: A
authors.initials: A
authors.lastname: Spang
authors.forename: K
authors.initials: K
authors.lastname: Grein
authors.forename: J
authors.initials: J
authors.lastname: Steinkötter
authors.forename: M
authors.initials: M
authors.lastname: Melkonian
authors.forename: E
authors.initials: E
authors.lastname: Schiebel
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites; D001667:Binding, Competitive; D002118:Calcium / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000737:chemistry*; D002147:Calmodulin / Q000737:chemistry; D018797:Cell Cycle Proteins / Q000737:chemistry; D000460:Chlorophyta; D002850:Chromatography, Gel; D002868:Chromosomal Proteins, Non-Histone; D002942:Circular Dichroism; D003285:Contractile Proteins / Q000737:chemistry*; D006801:Humans; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011485:Protein Binding; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D012441:Saccharomyces cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship
chemical_list: C083769:CDC31 protein, S cerevisiae; D002135:Calcium-Binding Proteins; D002147:Calmodulin; D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D003285:Contractile Proteins; D029701:Saccharomyces cerevisiae Proteins; C056608:caltractin; D002118:Calcium