Phase-Separated NDF-FACT Condensates Facilitate Transcription Elongation on Chromatin

This dataset contains single-molecule nucleosome transcription and nucleosome unwrapping data used in Li & Burgos-Bravo et al., 2025 (Nature Cell Biology). The study investigates how the transcription elongation factors NDF and FACT cooperate to facilitate RNA Polymerase II (Pol II) progression through nucleosomal barriers via formation of phase-separated condensates. Using high-resolution dual-trap optical tweezers and the Lumicks C-Trap instrument (integrating optical tweezers with confocal fluorescence detection), we collected real-time transcription trajectories and nucleosome unwrapping/rewrapping traces in the presence or absence of NDF and/or FACT.
The source data includes:
- Raw transcription traces of Pol II transcribing through a nucleosome, used to quantify Pol II residence time (Fig. 3B, 3C, Extended Data Fig. 3A).
- Raw transcription traces and confocal fluorescence scans obtained from the C-Trap instrument and used to visualize condensate formation during transcription at the single-molecule level (Fig. 3E, 3F, and Extended Data Fig. 3C, 3E, 3F). This includes both the dataset shown in the manuscript and additional representative traces not included in the figures.
- Raw force-extension curves showing nucleosome disassembly products across successive pulling cycles (Extended Data Fig. 3I).