Structural and dynamic characterization of intrinsically disordered human securin by NMR spectroscopy.
J Am Chem Soc
; 130(50): 16873-9, 2008 Dec 17.
Article
em En
| MEDLINE
| ID: mdl-19053469
ABSTRACT
Understanding the molecular action of securin, the inhibitor of separase in mitosis, is of immense theoretical and biomedical importance. The residue-level structural description of an intrinsically disordered protein of this length (202 amino acids, containing 24 prolines), however, represents a particular challenge. Here we combined (1)H-detected and (13)C-detected protonless NMR experiments to achieve full assignment of securin's backbone amide resonances. Chemical shifts, (15)N relaxation rates (R(1), R(2), (1)H-(15)N NOEs), (1)H exchange rates with the solvent (CLEANEX-PM), and (1)H-(15)N residual dipolar couplings were determined along the entire length of the protein. This analysis showed that securin is not entirely disordered, but segregates into a largely disordered N-terminal half and a C-terminal half with transient segmental order, within which the segment D(150)-F(159) has a significant helical tendency and segments E(113)-S(127) and W(174)-L(178) also show a significant deviation from random-coil behavior. These results, in combination with bioinformatic and biochemical data on the securin/separase interaction, shed light on the inhibitory action of securin on separase.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Neoplasias
Limite:
Humans
Idioma:
En
Revista:
J Am Chem Soc
Ano de publicação:
2008
Tipo de documento:
Article
País de afiliação:
Hungria