Histone acetylation readers Bdf1 and Yaf9 direct SWR1 remodeler to +1 nucleosome

The histone variant H2A.Z marking permissive chromatin is deposited by the multicomponent SWR1 chromatin remodeler, which is targeted to nucleosome-free promoters by a DNA length-sensing module. How SWR1 is directed to the flanking acetylated +1 nucleosome, its physiological substrate, has been enigmatic. We show by live-cell, single-molecule tracking that SWR1 subunits Bdf1 and Yaf9 harboring histone acetylation reader domains differentially regulate chromatin binding: Bdf1 promotes SWR1 association, while Yaf9-YEATS slows its dissociation. Notably, single-molecule tracking and genome-wide ChIP-exo reveal Bdf1 and Yaf9 contributions to global SWR1 targeting and histone exchange at +1 nucleosomes. Our findings highlight the in-cell biochemistry of histone readers and suggest a generalizable, two-stage mechanism wherein acetylated nucleosome interactions initially constrain 3D diffusion of SWR1 to increase local concentration, followed by stochastic 1D diffusion at NFRs with directional ..., , , # Histone acetylation readers Bdf1 and Yaf9 direct SWR1 remodeler to +1 nucleosome

[https://doi.org/10.5061/dryad.kd51c5bgq](https://doi.org/10.5061/dryad.kd51c5bgq)

### Overview

This dataset supports the findings of the study titled *“Histone acetylation readers Bdf1 and Yaf9 direct SWR1 remodeler to +1 nucleosome,”* which investigates how chromatin remodelers are directed to specific genomic loci via interactions with histone post-translational modifications (PTMs). Specifically, the study focuses on the SWR1 complex in budding yeast (*S. cerevisiae*), which catalyzes the ATP-dependent exchange of histone H2A with its variant H2A.Z—a key mark of transcriptionally active chromatin.

Live-cell single-molecule tracking (SMT) was employed to directly observe the binding dynamics of SWR1 and H2A.Z in wild-type and various mutant yeast strains. Using fluorescently tagged Halo fusions of Swr1 and H2A.Z, and high-temporal-resolution imaging with Janelia Fluor 552 dye, the study dissected t...,