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Updated: May 19, 2026
10:41
An Integrated Platform for Genome-wide Mapping of Chromatin States Using High-throughput ChIP-sequencing in Tumor Tissues
Published on: April 5, 2018
Genome-wide chromatin recording resolves dynamic cell state changes
Yodai Takei1,2, Jordan A Lay1,3, James M Linton1
1Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
Biorxiv : the Preprint Server for Biology
|May 18, 2026
Summary
LagTag enables recovery of earlier and endpoint chromatin states in the same cells. This method tracks dynamic chromatin changes during cell differentiation, advancing temporally resolved chromatin profiling.
Area of Science:
- Molecular Biology
- Genomics
- Epigenetics
Background:
- Understanding chromatin's role in cell behavior is crucial but limited by endpoint assays.
- Existing chromatin profiling methods cannot capture dynamic changes over time within the same cells.
Purpose of the Study:
- To develop a novel method for temporally resolved chromatin profiling.
- To enable the recovery of both early and endpoint chromatin states from the same mammalian cells.
Main Methods:
- LagTag utilizes transient expression of bacterial adenine methyltransferase fusions to record earlier DNA binding profiles.
- Adenine methylation profiles are subsequently used to recover earlier chromatin states via tagmentation and sequencing.
- Endpoint profiles of endogenous chromatin-associated proteins are recovered concurrently.
Main Results:
- LagTag profiles demonstrated strong alignment with established chromatin profiling methods in mouse and human cells.
- The method successfully recorded and recovered dynamic chromatin state transitions during mouse embryonic stem cell differentiation.
- Transcriptional signatures from pre- and post-differentiation timepoints were captured within the same cell population.
Conclusions:
- LagTag offers a groundbreaking approach for temporally resolved chromatin profiling.
- This method provides a foundation for studying dynamic epigenetic changes in biological processes.
- LagTag facilitates a deeper understanding of how chromatin state influences cell fate decisions.
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