title: Photocontrol of calmodulin interaction with target peptides using azobenzene derivative.
abstract: Calmodulin (CaM), a physiologically important Ca(2+)-binding protein, participates in numerous cellular regulatory processes. It is dumbbell shaped and contains two globular domains connected by a short alpha-helix. Each of the globular domains has two Ca(2+)-binding sites, the EF hands. CaM undergoes a conformational change upon binding to Ca(2+), which enables it to bind to specific proteins for specific responses. Here, we successfully photocontrolled CaM binding to its target peptide using the photochromic compound N-(4-phenylazophenyl) maleimide (PAM), which reversibly undergoes cis-trans isomerization upon ultraviolet (UV) and visible (VIS) light irradiation. In order to specifically incorporate PAM, CaM mutants having reactive cysteine residues in the functional region were prepared; PAM was stoichiometrically incorporated into the cysteine residues in these mutants. Further, we prepared the target peptide, M13, fused with yellow fluorescent protein (YFP) to monitor the CaM-M13 peptide interaction. The binding of the PAM-CaM mutants, N60C, D64C and M124C, to M13-YFP was reversibly photocontrolled upon UV-VIS light irradiation at appropriate Ca(2+) concentrations.
authors: Division of Bioinformatics, Graduate School of Engineering, Soka University, Hachioji, Tokyo 192-8577, Japan.
authors: Hideki
authors: H
authors: Shishido
authors: Masafumi D
authors: MD
authors: Yamada
authors: Kazunori
authors: K
authors: Kondo
authors: Shinsaku
authors: S
authors: Maruta
mesh_terms: D001391:Azo Compounds / Q000737:chemistry / Q000494:pharmacology* / Q000528:radiation effects; D001665:Binding Sites; D002118:Calcium / Q000378:metabolism; D002147:Calmodulin / Q000378:metabolism*; D010455:Peptides / Q000378:metabolism*; D055668:Photochemical Processes; D011485:Protein Binding; D011758:Pyrroles / Q000737:chemistry / Q000494:pharmacology* / Q000528:radiation effects; D013237:Stereoisomerism; D014466:Ultraviolet Rays
chemical_list: C546415:1-(4-phenyldiazenylphenyl)pyrrole-2,5-dione; D001391:Azo Compounds; D002147:Calmodulin; D010455:Peptides; D011758:Pyrroles; D002118:Calcium