ICSF

ICSF identifies conserved structural features within transcription factor binding sites to detect structural codes in sequentially degenerate positions that may be important for transcription factor recognition.

Key Features:

• Base-pair step parameters: Uses base-pair step parameters derived from high-resolution DNA crystal structures to describe relative displacement and orientation of adjacent base pairs.
• Focus on sequentially degenerate positions: Targets regions within binding sites that are not sequentially conserved but may harbor conserved structural information.
• Structural conservation discovery: Analyzes structural parameters to identify conserved structural features in sequentially degenerate areas of binding sites.
• Profile generation: Generates profiles of structural features along entire transcription factor binding sites to map spatial configurations.
• Application to JASPAR database: Applied to transcription factor binding sites in the JASPAR database and reported that ~one-third contain sequentially degenerate locations with highly conserved structural features (P-value ≥ 0.05).

Scientific Applications:

• Transcription factor recognition studies: Elucidates structural determinants that may contribute to transcription factor–DNA recognition beyond sequence conservation.
• Transcription factor binding site identification: Improves detection of binding sites in genomic sequences by incorporating structural conservation information.
• Gene regulation mechanisms: Provides insights into the molecular mechanisms underlying protein–DNA interactions and regulatory site architecture.

Methodology:

Derives base-pair step parameters from high-resolution DNA crystal structures, analyzes these structural parameters to detect conserved features in sequentially degenerate regions, generates structural feature profiles across binding sites, and applies the analysis to JASPAR binding sites reporting conserved features with P-value ≥ 0.05.