Dynamics of the Mrf-2 DNA-binding domain free and in complex with DNA

Citation
Ly. Zhu et al., Dynamics of the Mrf-2 DNA-binding domain free and in complex with DNA, BIOCHEM, 40(31), 2001, pp. 9142-9150
Citations number
35
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Biochemistry & Biophysics
Journal title
BIOCHEMISTRY
ISSN journal
0006-2960 → ACNP
Volume
40
Issue
31
Year of publication
2001
Pages
9142 - 9150
Database
ISI
SICI code
0006-2960(20010807)40:31<9142:DOTMDD>2.0.ZU;2-3
Abstract
Mrf-2 is a member of a new class of DNA-binding proteins known as the AT-ri ch interaction domain family or ARID. Chemical shift indices and characteri stic NOE values indicate that the three-dimensional structure of the Mrf-2 ARID in complex with DNA is nearly identical to that of the free protein. T he backbone dynamics of the Mrf-2 domain free and in complex with DNA have been characterized by N-15 NMR relaxation measurements and model-free analy sis. Chemical shift perturbations and dynamic studies suggest that two flex ible interhelical loops, the flexible C-terminal tail, and one alpha -helix are involved in DNA recognition, indicating the importance of protein dyna mics in DNA binding. Some well-structured regions, in particular the putati ve DNA-contacting helix, in Mrf-2 show a decrease in the order parameters ( S-2) upon complex formation. The less well-structured loops and the unstruc tured C-terminus show reduced flexibility upon DNA binding. In addition, th e model-free analysis indicates motions on the picosecond to nanosecond and micro- to millisecond time scales at the DNA-binding surface of the bound Mrf-2 ARID, suggesting a model where interactions between the protein and D NA are highly dynamic.