Structure of human upstream binding factor HMG box 5 and site for binding of the cell-cycle regulatory factor TAF1
Rong, H., Li, Y., Shi, X., Zhang, X., Gao, Y., Dai, H., Teng, M.K., Niu, L.W., Liu, Q., Hao, Q.(2007) Acta Crystallogr D Biol Crystallogr 63: 730-737
- PubMed: 17505112 
- DOI: https://doi.org/10.1107/S0907444907017027
- Primary Citation of Related Structures:  
2HDZ - PubMed Abstract: 
The fifth HMG-box domain in human upstream binding factor (hUBF) contributes to the synthesis of rRNA by RNA polymerase I (Pol I). The 2.0 A resolution crystal structure of this protein has been solved using the single-wavelength anomalous dispersion method (SAD). The crystal structure and the reported NMR structure have r.m.s. deviations of 2.18-3.03 A for the C(alpha) atoms. However, there are significant differences between the two structures, with displacements of up to 9.0 A. Compared with other HMG-box structures, the r.m.s. deviations for C(alpha) atoms between hUBF HMG box 5 and HMG domains from Drosophila melanogaster protein D and Rattus norvegicus HMG1 are 1.5 and 1.6 A, respectively. This indicates that the differences between the crystal and NMR structures of hUBF HMG box 5 are larger than those with its homologous structures. The differences between the two structures potentially reflect two states with different structures. The specific interactions between the hUBF HMG box 5 and the first bromodomain of TBP-associated factor 1 (TAF1) were studied by ultrasensitive differential scanning calorimetry and chemical shift perturbation. Based on these experimental data, possible sites in hUBF HMG box 5 that may interact with the first bromodomain of TAF1 were proposed.
Organizational Affiliation: 
Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.