Structural characterization of a minimal functional transactivation domain from the human glucocorticoid receptor.

• DOI: 10.1073/pnas.92.5.1699
• Publication Date: 2006-05-31T13:27:59Z
• Authors: K Dahlman-Wright; H Baumann; I J McEwan; T Almlöf; A P Wright; J A Gustafsson; T Härd
• Keywords: Alpha helix; Helix (gastropod)

A 58-amino acid polypeptide containing the functional core region, tau 1 core, of major transactivation domain human glucocorticoid receptor has been expressed in Escherichia coli and purified to homogeneity. The retains 60-70% activity intact when assayed vivo or vitro. This report describes a structural characterization peptide fragment. Circular dichroism spectroscopy shows that larger fragment encompassing are largely unstructured water solution under variety pH conditions. however, acquires significant alpha-helical structure analyzed presence trifluoroethanol, an agent favors secondary formation regions have propensity for conformation. Two- three-dimensional NMR 15N-labeled allowed sequential assignment 1H 15N resonances identification three protein segments with character. Potentially helix-breaking proline substitutions, proposed regions, lead reduced activity, suggesting alpha-helices important vivo.