ISSN:
1573-5001
Keywords:
isotope labeling
;
nucleic acids
;
protein–DNA complex
;
sequential resonance assignment
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
Notes:
Abstract Nearly complete 1H, 13C and15 N NMR assignments have been obtained for a doubly labeled 14-base pair DNA duplex in solution both in the free state and complexed with the uniformly 15N-labeled Antennapedia homeodomain. The DNA was either fully 13C,15N-labeled or contained uniformly 13C, 15N-labeled nucleotides only at those positions which form the protein–DNA interface in the previously determined NMR solution structure of the Antennapedia homeodomain–DNA complex. The resonance assignments were obtained in three steps: (i) identification of the deoxyribose spin systems via scalar couplings using 2D and 3D HCCH-COSY and soft-relayed HCCH-COSY; (ii) sequential assignment of the nucleotides via1 H–1H NOEs observed in 3D13 C-resolved NOESY; and (iii) assignment of the imino and amino groups via 1H–1H NOEs and15 N–1H correlation spectroscopy. The assignment of the duplex in the 17 kDa protein–DNA complex was greatly facilitated by the fact that 1H signals of the protein were filtered out in 13C-resolved spectroscopy and by the excellent carbon chemical shift dispersion of the DNA duplex. Comparison of corresponding 13C chemical shifts of the free and the protein-bound DNA indicates conformational changes in the DNA upon complex formation.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1008280117211
