The SWI/SNF chromatin remodeling complex plays important roles in gene regulation and it is classified as the SWI/SNF complex in yeast and BAF complex in vertebrates. BAF57, one of the subunits that forms the chromatin remodeling complex core, is well conserved in the BAF complex of vertebrates, which is replaced by bap111 in the Drosophila BAP complex and does not have a counterpart in the yeast SWI/SNF complex. This suggests that BAF57 is a key component of the chromatin remodeling complex in higher eukaryotes. BAF57 contains a HMG domain, which is widely distributed among various proteins and functions as a DNA binding motif. Most proteins with HMG domain bind to four-way junction (4WJ) DNA. Here, we report the crystal structure of the HMG domain of BAF57 (BAF57HMG) at a resolution of 2.55 Å. The structure consists of three α-helices and adopts an L-shaped form. The overall structure is stabilized by a hydrophobic core, which is formed by hydrophobic residues. The binding affinity between BAF57HMG and 4WJ DNA is determined as a 295.83 ± 1.05 nM using a fluorescence quenching assay, and the structure revealed 4WJ DNA binding site of BAF57HMG. Our data will serve structural basis in understanding the roles of BAF57 during chromatin remodeling process.
|Journal||Biochemical and Biophysical Research Communications|
|Publication status||Accepted/In press - 2020|
Bibliographical noteFunding Information:
This work was supported by the Mid-career Researcher Program ( NRF-2017R1A2B2008483 , NRF-2019M3E5D6063903 , and NRF-2017M3A9F6029753 to W. Lee, and NRF-20161A6A3A04010213 to J.H. Yun) through the National Research Foundation of Korea (NRF) and the Brain Korea Plus (BK+) program (Y. Heo). We thank the staff of the beamline at the Pohang Accelerator Laboratory (PAL) for assistance during X-ray data collection.
All Science Journal Classification (ASJC) codes
- Molecular Biology
- Cell Biology