CHSalign

CHSalign aligns RNA secondary structures containing coaxial helical stacking (CHS) motifs for pairwise structural comparison and analysis.

Key Features:

• Coaxial Helical Stacking (CHS) focus: Handles RNA secondary structures that incorporate CHS motifs formed when three or more helices converge.
• Algorithms: Implements constrained tree matching and dynamic programming algorithms for aligning RNA secondary structure representations.
• Integration of predictive models: Incorporates Junction-Explorer for predicting coaxial stacking and RNAJAG for modeling junction topologies as tree graphs.
• Performance: Experimental evaluations involving thousands of alignments demonstrated improved accuracy relative to other tools when structures share similar CHS motifs or helical arrangements.

Scientific Applications:

• RNA structure annotation: Aids annotation of complex junctions featuring CHS motifs to inform structural and functional interpretation.
• Predictive modeling: Supports prediction of coaxial stacking and modeling of junction topologies as tree graphs for structural bioinformatics analyses.
• Comparative genomics: Enables comparative studies of RNA secondary structures across species or conditions to assess conservation and evolutionary relationships.

Methodology:

CHSalign applies Junction-Explorer predictions of coaxial stacking and RNAJAG tree-graph junction models combined with constrained tree matching and dynamic programming for pairwise alignment, and was evaluated on thousands of alignments.