Target recognition by calmodulin: the role of acid region contiguous to the calmodulin-binding domain of calcineurin A.
Small-angle X-ray scattering was used to investigate the role of acid region contiguous to the calmodulin-binding domain (391-414) of calcineurin in the target recognition by calmodulin. Three synthetic peptides with the residues 385-414, 380-414 and 374-414 of calcineurin A were used for this aim. The X-ray data are consistent with the fact that calmodulin binds all three peptides with or without Ca2+. Without Ca2+, the whole peptide including acid residues interacts with dumbbell shaped calmodulin, while the acid region is extruded from globular shaped calmodulin with Ca2+. Consequently, a conformation of sequence 374-414 in calcineurin might be changed by Ca2+-signal via calmodulin, suggesting the consequence of this region with acid residues in the full activation mechanism of calcineurin by Ca2+-bound calmodulin.
Graduate Program of Human Sensing and Functional Sensor Engineering, Graduate School of Science and Engineering, Yamagata University, 4-3-16, Jo-nan, Yonezawa 992-8510, Japan.
Masahiro
M
Noguchi
Yoshinobu
Y
Izumi
Hidenori
H
Yoshino
D000143:Acids / Q000737:chemistry / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D019703:Calcineurin / Q000737:chemistry* / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism / Q000494:pharmacology; D002147:Calmodulin / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D051381:Rats; D055672:Static Electricity; D013379:Substrate Specificity; D014961:X-Ray Diffraction
D000143:Acids; D002147:Calmodulin; D010446:Peptide Fragments; D019703:Calcineurin; D002118:Calcium