Short DNA sequence patterns accurately identify broadly active human enhancers.

Area of Science:

• Genomics
• Molecular Biology
• Bioinformatics

Background:

• Enhancers are DNA regulatory elements controlling gene expression with diverse activity patterns.
• Sequence characteristics, like transcription factor (TF) binding motifs, influence enhancer activity, but the precise regulatory logic remains unclear.
• Short dinucleotide repeat motifs (DRMs) were previously suggested to drive broad activity in Drosophila enhancers, but their conservation in humans is unknown.

Purpose of the Study:

• To comprehensively analyze the relationship between short DNA sequence patterns and human enhancer activity across numerous contexts.
• To investigate the role of DRMs in human enhancer activity and their evolutionary conservation compared to Drosophila.

Main Methods:

• Analyzed 38,538 human enhancers across 411 contexts.
• Employed a machine-learning framework to assess the predictive power of short sequence motifs, including DRMs, on enhancer activity.
• Compared motif enrichment patterns and TF binding preferences between human and Drosophila enhancers.

Main Results:

• Short sequence motif occurrence patterns accurately predicted broadly active human enhancers.
• DRMs were weakly predictive of broad human enhancer activity and showed different enrichment patterns than in Drosophila.
• GC-rich sequence motifs were significantly associated with broad enhancer activity in humans, and associated TFs recognized GC-rich motifs.

Conclusions:

• Specific sequence motifs are crucial for broadly active human enhancers.
• The regulatory role of DRMs in enhancer activity is not conserved across species.
• A computational framework was established for studying enhancer sequence logic.