A structural and dynamic characterization of the EF-hand protein CLSP.
The structure and dynamics of human calmodulin-like skin protein (CLSP) have been characterized by NMR spectroscopy. The mobility of CLSP has been found to be different for the N-terminal and C-terminal domains. The isolated domains were also expressed and analyzed. The structure of the isolated C-terminal domain is presented. The N-terminal domain is characterized by four stable helices, which experience large fluctuations. This is shown to be due to mutations in the hydrophobic core. The overall N-terminal domain behavior is similar both in the full-length protein and in the isolated domain. By exploiting the capability of Tb3+ bound to CLSP to induce partial orientation of the molecule in a magnetic field, restricted motion of one domain with respect to the other was proved. By using NMR, ITC, and ESI-MS, the calcium and magnesium binding properties were investigated. Finally, CLSP is framed into the evolutionary scheme of the calmodulin-like family.
Babini
Elena
E
Centro Risonanze Magnetiche, University of Florence, Via Sacconi 6, 50019 Sesto Fiorentino, Florence, Italy.
Bertini
Ivano
I
Capozzi
Francesco
F
Chirivino
Emanuele
E
Luchinat
Claudio
C
D000595:Amino Acid Sequence; D002118:Calcium / Q000737:chemistry; D002135:Calcium-Binding Proteins / Q000737:chemistry* / Q000235:genetics; D020832:EF Hand Motifs / Q000235:genetics; D006801:Humans; D008274:Magnesium / Q000737:chemistry; D008969:Molecular Sequence Data; D009154:Mutation; D019906:Nuclear Magnetic Resonance, Biomolecular; D017510:Protein Folding; D017434:Protein Structure, Tertiary / Q000235:genetics; D013725:Terbium / Q000737:chemistry
C408467:CALML5 protein, human; D002135:Calcium-Binding Proteins; D013725:Terbium; D008274:Magnesium; D002118:Calcium