Single-molecule FRET analysis of DNA binding and bending by yeast HMGB protein Nhp6A.

ABSTRACT: High-mobility group B (HMGB) proteins bind duplex DNA without sequence specificity, facilitating the formation of compact nucleoprotein structures by increasing the apparent flexibility of DNA through the introduction of DNA kinks. It has remained unclear whether HMGB binding and DNA kinking are simultaneous and whether the induced kink is rigid (static) or flexible. The detailed molecular mechanism of HMGB-induced DNA 'softening' is explored here by single-molecule fluorescence resonance energy transfer studies of single yeast Nhp6A (yNhp6A) proteins binding to short DNA duplexes. We show that the local effect of yNhp6A protein binding to DNA is consistent with formation of a single static kink that is short lived (lifetimes of a few seconds) under physiological buffer conditions. Within

SUBMITTER: Coats JE 

PROVIDER: S-EPMC3554232 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature