High-throughput mapping of regulatory DNA

Area of Science:

• Genetics
• Molecular Biology
• Genomics

Background:

• Understanding cis-regulatory DNA's role in gene expression is crucial but challenging.
• High-throughput methods are needed to analyze regulatory elements in their native genomic context.

Purpose of the Study:

• To present the multiplexed editing regulatory assay (MERA), a novel CRISPR-Cas9-based approach.
• To quantify the functional impact of cis-regulatory DNA on gene expression at base-pair resolution.

Main Methods:

• MERA utilizes CRISPR-Cas9 to tile thousands of mutations across cis-regulatory regions (~40 kb).
• Green fluorescent protein (GFP) reporters are used to measure gene activity.
• Thousands of functional and nonfunctional genotypes are compared to identify regulatory motifs.

Main Results:

• MERA provides quantitative insights into the contribution of cis-regulatory regions to gene expression.
• Proximal and distal regulatory elements essential for embryonic stem cell-specific gene expression were identified.
• Unmarked regulatory elements (UREs) controlling gene expression were discovered, lacking typical enhancer features.

Conclusions:

• MERA is an effective high-throughput tool for dissecting gene regulation.
• The study identified key regulatory elements and novel UREs, advancing our understanding of gene control mechanisms.