title: A chirality change in XPC- and Sfi1-derived peptides affects their affinity for centrin.
abstract: The Ca(2+)-binding protein centrin binds to a hydrophobic motif (W(1)xxL(4)xxxL(8)) included in the sequence of several cellular targets: XPC (xeroderma pigmentosum group C protein), Sfi1 (suppressor of fermentation-induced loss of stress resistance protein1), and Sac3 [the central component of the transcription and mRNA export (TREX-2) complex]. However, centrin binding occurs in a reversed orientation (L(8)xxxL(4)xxW(1)) for Sfi1 and Sac3 compared with XPC. Because D-peptides have been investigated for future therapeutic use, we analyzed their centrin-binding properties. Their affinity for centrin was measured using isothermal titration calorimetry. The chirality change in the target-derived peptides affected their ability to bind centrin in a specific manner depending on the sequence orientation of the centrin-binding motif. In contrast to L-XPC-P10, D-XPC-P10 bound C-HsCen1 in a Ca(2+)-dependent manner and to a lesser extent. D-XPC-P10 exhibited a reduced affinity for C-HsCen1 (Ka=0.064 × 10(6) M(-1)) by a factor of 2000 compared with L-XPC-P10 (Ka=132 × 10(6) M(-1)). D-peptides have a lower affinity than L-peptides for centrin, and the strength of this affinity depends on the sequence orientation of the target-derived peptides. The residual affinity observed for D-XPC suggests that the use of d-peptides represents a promising strategy for inhibiting centrin binding to its targets.
authors.affiliation: Institut Curie-Centre de Recherche, F-91405 Orsay Cédex, France; Institut National de la Santé et de la Recherche Médicale (INSERM) U759, F-91405 Orsay Cédex, France.
authors.forename: Dora
authors.initials: D
authors.lastname: Grecu
authors.affiliation: Institut Curie-Centre de Recherche, F-91405 Orsay Cédex, France; Institut National de la Santé et de la Recherche Médicale (INSERM) U759, F-91405 Orsay Cédex, France; UMR CNRS 7203, Paris Cédex 05, France; ENS Ecole Normale Supérieure de Paris, Paris Cédex 05, France; Université Paris 6, Paris Cédex 05, France.
authors.forename: Victor Paul Raj
authors.initials: VP
authors.lastname: Irudayaraj
authors.affiliation: Institut Curie-Centre de Recherche, F-91405 Orsay Cédex, France; Institut National de la Santé et de la Recherche Médicale (INSERM) U759, F-91405 Orsay Cédex, France; UMR9187-U1196, F-91405 Orsay Cédex, France.
authors.forename: Juan
authors.initials: J
authors.lastname: Martinez-Sanz
authors.affiliation: UMR CNRS 7203, Paris Cédex 05, France; ENS Ecole Normale Supérieure de Paris, Paris Cédex 05, France; Université Paris 6, Paris Cédex 05, France.
authors.forename: Jean-Maurice
authors.initials: JM
authors.lastname: Mallet
authors.affiliation: Institut Curie-Centre de Recherche, F-91405 Orsay Cédex, France; Institut National de la Santé et de la Recherche Médicale (INSERM) U759, F-91405 Orsay Cédex, France. Electronic address: liliane.assairi@orange.fr.
authors.forename: Liliane
authors.initials: L
authors.lastname: Assairi
mesh_terms: D020418:Algal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D000595:Amino Acid Sequence; D001665:Binding Sites; D002135:Calcium-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D000460:Chlorophyta / Q000737:chemistry*; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D005420:Flavoproteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry*; D010744:Phosphoric Monoester Hydrolases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013237:Stereoisomerism; D013816:Thermodynamics
chemical_list: D020418:Algal Proteins; C580665:CETN1 protein, human; C472752:CETN2 protein, human; D002135:Calcium-Binding Proteins; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D005420:Flavoproteins; D010455:Peptides; D011994:Recombinant Proteins; C545864:Sfi1 protein, human; C086984:XPC protein, human; C522215:FIG4 protein, human; D010744:Phosphoric Monoester Hydrolases
keywords: Centrin; Circular dichroism; Isothermal titration calorimetry; Retro-inverso peptides; Sfi1; XPC; d-Peptides