UnderIICRMS

UnderIICRMS performs alignment-free comparisons of cis-regulatory modules (CRMs) and unassembled genomes using variable-length patterns to detect regulatory sequence similarity and compare NGS read datasets.

Key Features:

• Parameter-Free Approach: Operates without predefined parameters, removing the need for parameter tuning across datasets and biological contexts.
• Variable-Length Patterns: Utilizes variable-length words/patterns instead of fixed-length k-mers to capture length variability in CRMs and genomic sequences.
• Enhancer Clustering and Functional Correlation: Identifies functionally similar enhancers and clusters within cis-regulatory modules by employing a similarity measure that detects related regulatory sequences.
• Discrimination of Functionally Related Enhancers: Distinguishes enhancers active in different tissues, as demonstrated on simulated data and ChIP-seq sequences including mouse enhancers.
• Genome Comparison Without Assembly: Enables direct comparison of unassembled genomes using NGS reads when reference genomes are unavailable.
• Similarity Measure Incorporating Reverses and Reverse-Complements: Defines a similarity measure based on variable-length patterns including reverses and reverse-complements and their statistical and syntactical properties.
• Performance in Genome Discrimination: Evaluated against other alignment-free statistics on simulated and real genomes and shown to outperform fixed-length pattern methods, particularly on real genome NGS read data.

Scientific Applications:

• Comparative Genomic Studies: Facilitates assembly-free comparison of genomes from NGS reads, applicable to non-model organisms and newly sequenced species.
• Regulatory Sequence Analysis: Supports analysis of enhancers and CRM architecture to infer functional correlations among regulatory elements.
• Evolutionary Biology: Enables study of evolutionary relationships between genomes using alignment-free comparisons of NGS data in the absence of a reference genome.

Methodology:

Performs alignment-free sequence comparisons using variable-length patterns/words in a parameter-free framework; computes a similarity measure that includes reverses and reverse-complements and assesses statistical and syntactical properties; validated on simulated data and ChIP-seq sequences and compared against other alignment-free statistics using unassembled NGS reads.