title: Structural and dynamic aspects of Ca2+ and Mg2+ binding of the regulatory domains of the Na+/Ca2+ exchanger.
abstract: Intracellular Ca2+ regulates the activity of the NCX (Na+/Ca2+ exchanger) through binding to the cytosolic CBD (Ca2+-binding domain) 1 and CBD2. In vitro studies of the structure and dynamics of CBD1 and CBD2, as well as studies of their kinetics and thermodynamics of Ca2+ binding, greatly enhanced our understanding of NCX regulation. We describe the fold of the CBDs in relation to other known structures and review Ca2+ binding of the different CBD variants from a structural perspective. We also report on new findings concerning Mg2+ binding to the CBDs and finally we discuss recent results on CBD1-CBD2 interdomain interactions.
authors.affiliation: Protein Biophysics, Institute for Molecules and Materials, Radboud University Nijmegen, Geert Grooteplein 26-28, 6525 GA Nijmegen, The Netherlands.
authors.forename: Vincent
authors.initials: V
authors.lastname: Breukels
authors.forename: Wouter G
authors.initials: WG
authors.lastname: Touw
authors.forename: Geerten W
authors.initials: GW
authors.lastname: Vuister
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D006801:Humans; D008274:Magnesium / Q000378:metabolism*; D008969:Molecular Sequence Data; D011485:Protein Binding; D055550:Protein Stability; D017434:Protein Structure, Tertiary; D019831:Sodium-Calcium Exchanger / Q000737:chemistry* / Q000378:metabolism*; D013329:Structure-Activity Relationship
chemical_list: D019831:Sodium-Calcium Exchanger; D008274:Magnesium; D002118:Calcium