Summary information and primary citation
- PDB-id
-
6uxw;
DSSR-derived features in text and
JSON formats; DNAproDB
- Class
- transcription-DNA
- Method
- cryo-EM (8.96 Å)
- Summary
- Swi-snf nucleosome complex with adp-befx
- Reference
-
Han Y, Reyes AA, Malik S, He Y (2020): "Cryo-EM
structure of SWI/SNF complex bound to a nucleosome."
Nature, 579, 452-455. doi:
10.1038/s41586-020-2087-1.
- Abstract
- The chromatin-remodelling complex SWI/SNF is highly
conserved and has critical roles in various cellular
processes, including transcription and DNA-damage
repair<sub>1,2</sub>. It hydrolyses ATP to
remodel chromatin structure by sliding and evicting histone
octamers<sub>3-8</sub>, creating DNA regions
that become accessible to other essential factors. However,
our mechanistic understanding of the remodelling activity
is hindered by the lack of a high-resolution structure of
complexes from this family. Here we report the
cryo-electron microscopy structure of Saccharomyces
cerevisiae SWI/SNF bound to a nucleosome, at near-atomic
resolution. In the structure, the actin-related protein
(Arp) module is sandwiched between the ATPase and the rest
of the complex, with the Snf2 helicase-SANT associated
(HSA) domain connecting all modules. The body contains an
assembly scaffold composed of conserved subunits Snf12
(also known as SMARCD or BAF60), Snf5 (also known as
SMARCB1, BAF47 or INI1) and an asymmetric dimer of Swi3
(also known as SMARCC, BAF155 or BAF170). Another conserved
subunit, Swi1 (also known as ARID1 or BAF250), resides in
the core of SWI/SNF, acting as a molecular hub. We also
observed interactions between Snf5 and the histones at the
acidic patch, which could serve as an anchor during active
DNA translocation. Our structure enables us to map and
rationalize a subset of cancer-related mutations in the
human SWI/SNF complex and to propose a model for how
SWI/SNF recognizes and remodels the +1 nucleosome to
generate nucleosome-depleted regions during gene
activation<sub>9</sub>.
