Open Access31 P NMR analysis of the DNA conformation induced by protein binding
Author(s) -
Castagné Claire,
Murphy Elizabeth C.,
Gronenborn Angela M.,
Delepierre Muriel
Publication year - 2000
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1046/j.1432-1327.2000.01124.x
Subject(s) - intercalation (chemistry) , dna , crystallography , chemistry , base pair , isoleucine , stereochemistry , testis determining factor , hmg box , nuclear magnetic resonance , dna binding protein , physics , biochemistry , amino acid , leucine , inorganic chemistry , y chromosome , transcription factor , gene
Complexes of the HMG box protein SRY with two duplexes of 8 and 14 base pairs have been studied by 31 P NMR and complete assignment of all phosphorus signals of the bound DNA duplexes are presented. While for the free DNA, all 31 P signals display limited spectral dispersion (< 0.8 p.p.m.) for the bound duplexes, 31 P resonances are spread over 2 p.p.m. Based on the previously published 3D structure of hSRY‐HMG, with the 8 mer it is demonstrated that the upfield shifted resonances correspond to the site of partial intercalation of an isoleucine side chain into the DNA. Moreover, the observation of significant difference in linewidths between the two duplexes allows to estimate lifetime of the complexes from 31 P– 31 P 2D exchange experiments.