Functional cis-regulatory genomics for systems biology.

Area of Science:

• Genomics
• Systems Biology
• Molecular Biology

Background:

• Gene expression is regulated by interactions between trans-regulatory factors and cis-regulatory DNA sequences, forming gene regulatory networks (GRNs).
• Experimental validation of GRN models is crucial but currently limited by slow, demanding methods for discovering and testing cis-regulatory modules (CRMs).
• A bottleneck exists in genomic systems biology due to the laborious nature of current cis-regulatory analysis techniques.

Purpose of the Study:

• To develop a high-throughput method for the simultaneous discovery and quantitative characterization of CRMs.
• To significantly increase the speed and efficiency of cis-regulatory analysis.
• To facilitate the construction and validation of gene regulatory network models.

Main Methods:

• A novel high-throughput approach using DNA sequence tags to "barcode" CRM expression constructs.
• Mixing barcoded constructs, injecting them into sea urchin eggs, and subsequently deconvolving the data.
• Utilizing DNA-tag reporters for rapid discovery and simultaneous high-resolution temporal characterization of CRM activities.

Main Results:

• The DNA-tagging method increased the rate of cis-regulatory analysis by over 100-fold compared to conventional assays.
• Successfully discovered 81 active CRMs from 37 unexplored sea urchin genes.
• Obtained simultaneous temporal characterization of over 80 CRMs, with an average of 2-3 CRMs per gene, comprehensively covering endogenous expression phases.

Conclusions:

• This high-throughput approach dramatically accelerates cis-regulatory analysis, overcoming current bottlenecks in genomic systems biology.
• The method enables efficient discovery and characterization of CRMs, significantly advancing GRN construction and validation.
• This technique is poised to qualitatively alter practices in regulatory systems biology and related fields.