Promoter G-quadruplex structures regulate tissue-specific gene expression and functional differentiation in Bombyx...

Area of Science:

• Molecular Biology
• Genomics
• Epigenetics

Background:

• DNA G-quadruplexes (G4s) are noncanonical structures crucial for gene transcription regulation.
• Tissue-specific gene expression is vital for multicellular organism development.
• The role of G4s in tissue-specific gene regulation is largely unknown.

Purpose of the Study:

• Investigate G4 distribution and function in silkworm brain and fat body.
• Explore the link between G4s and tissue-specific gene expression.
• Understand G4s' role in functional tissue differentiation.

Main Methods:

• Utilized G4-CUT&Tag, ATAC-seq, RNA-seq, and histone modification datasets.
• Analyzed G4 distribution in promoter regions.
• Assessed G4 folding patterns and their correlation with gene expression.

Main Results:

• Promoter G4s are enriched in open chromatin and active histone marks, correlating with transcriptional activation.
• G4 folding patterns differ between brain and fat body, linked to tissue-specific gene expression.
• Brain-specific G4s associate with neural pathways; fat body-specific G4s associate with metabolic pathways.
• G4 stabilization by pyridostatin disrupted gene expression and impaired tissue development (neurogenesis, lipid metabolism).

Conclusions:

• G4s act as dynamic epigenetic modulators.
• G4s shape tissue-specific gene expression patterns.
• G4s coordinate functional differentiation in insects.