NMR structural characterization of the N-terminal domain of the adenylyl cyclase-associated protein (CAP) from Dictyostelium discoideum.
Cyclase-associated proteins (CAPs) are highly conserved, ubiquitous actin binding proteins that are involved in microfilament reorganization. The N-termini of CAPs play a role in Ras signaling and bind adenylyl cyclase; the C-termini bind to G-actin. We report here the NMR characterization of the amino-terminal domain of CAP from Dictyostelium discoideum (CAP(1-226)). NMR data, including the steady state (1)H-(15)N heteronuclear NOE experiments, indicate that the first 50 N-terminal residues are unstructured and that this highly flexible serine-rich fragment is followed by a stable, folded core starting at Ser 51. The NMR structure of the folded core is an alpha-helix bundle composed of six antiparallel helices, in a stark contrast to the recently determined CAP C-terminal domain structure, which is solely built by beta-strands.
Mavoungou
Chrystelle
C
Max Planck Institute for Biochemistry, 82152 Martinsried, Germany.
Israel
Lars
L
Rehm
Till
T
Ksiazek
Dorota
D
Krajewski
Marcin
M
Popowicz
Grzegorz
G
Noegel
Angelika A
AA
Schleicher
Michael
M
Holak
Tad A
TA
D000595:Amino Acid Sequence; D000818:Animals; D018797:Cell Cycle Proteins / Q000737:chemistry*; D018360:Crystallography, X-Ray; D003598:Cytoskeletal Proteins / Q000737:chemistry*; D004023:Dictyostelium / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D013058:Mass Spectrometry; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D017510:Protein Folding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012694:Serine / Q000737:chemistry; D015398:Signal Transduction; D013696:Temperature; D014965:X-Rays
D018797:Cell Cycle Proteins; D003598:Cytoskeletal Proteins; D012694:Serine