Screening for protein-DNA interactions by automatable DNA-protein interaction ELISA

Area of Science:

• Molecular Biology
• Genomics
• Biochemistry

Background:

• DNA-binding proteins (DBPs) regulate gene expression, but their DNA-binding motifs are often unknown.
• Existing methods for motif discovery lack high-throughput and automation capabilities.

Purpose of the Study:

• To develop an automatable DNA-protein-interaction (DPI)-ELISA screen for high-throughput, de novo identification of DNA-binding motifs.
• To demonstrate the method's efficiency and applicability for various DBPs.

Main Methods:

• An optimized double-stranded DNA (dsDNA) probe library was used in a DNA-protein-interaction (DPI)-ELISA screen.
• The screen was performed manually and with standard laboratory automation.
• Analysis of protein extracts and DNA-binding domains of specific DBPs (AtWRKY11, AtbZIP63, AtWRKY33, AtTIFY1).

Main Results:

• The DPI-ELISA screen successfully identified hexanucleotide DNA-binding motifs with high throughput.
• It revealed the full spectrum of binding preferences for known and uncharacterized DBPs.
• A TGATCA-consensus motif was discovered for AtTIFY1, with the GATC-core being essential for binding, confirmed by in vivo assays.

Conclusions:

• The automatable DPI-ELISA screen is a valuable tool for de novo DNA-binding motif identification of DBPs.
• This method facilitates a deeper understanding of gene regulation across diverse organisms.
• It offers a high-throughput and automatable alternative to existing motif discovery techniques.