A reverse chromatin immunoprecipitation technique based on the CRISPR-dCas9 system.

Area of Science:

• Molecular Biology
• Genomics
• Biotechnology

Background:

• Studying DNA-protein interactions is vital for understanding biological processes.
• Current DNA-protein interaction technologies rely on DNA hybridization, which lacks specificity and efficiency.
• RNA-guided DNA recognition offers high specificity and efficiency, presenting an alternative approach.

Purpose of the Study:

• To develop a novel DNA-binding protein capture technology overcoming limitations of hybridization-based methods.
• To introduce the reverse chromatin immunoprecipitation based on CRISPR-dCas9 system (R-ChIP-dCas9) for plant genomics.
• To identify upstream regulators of the NAC transcription factor BpNAC090 in birch plants.

Main Methods:

• Utilized the clustered regularly interspaced palindromic repeats (CRISPR)-dead Cas9 (dCas9) system fused with Strep-Tag II.
• Employed transient genetic transformation for expression of dCas9 and guide RNA (gRNA) in birch (Betula platyphylla) plants.
• Applied StrepTactin affinity purification, chromatin sonication, and mass spectrometry for protein identification.

Main Results:

• Successfully identified upstream regulators of the NAC transcription factor BpNAC090.
• Discovered 32 transcription factors potentially regulating BpNAC090.
• Validated the reliability of the R-ChIP-dCas9 method through complementary techniques like chromatin immunoprecipitation and yeast one-hybrid assays.

Conclusions:

• The R-ChIP-dCas9 system provides a highly specific and efficient method for studying DNA-protein interactions.
• This technology is adaptable to various plant species and does not require a stable transformation system.
• R-ChIP-dCas9 has wide applications for identifying proteins bound to genomic DNA, advancing plant genomics research.