NMD Classifier: A reliable and systematic classification tool for nonsense-mediated decay events.

Area of Science:

• Molecular Biology
• Genomics
• Evolutionary Biology

Background:

• Nonsense-mediated decay (NMD) is a crucial cellular surveillance pathway that degrades messenger RNAs (mRNAs) containing premature termination codons (PTCs).
• NMD prevents the synthesis and accumulation of potentially harmful truncated proteins, playing roles in gene regulation and various biological processes.
• Understanding the evolutionary and regulatory origins of NMD-targeted transcripts (NMDTs) is challenging due to the complexity of analyzing NMD events.

Purpose of the Study:

• To develop a computational tool, NMD Classifier, for the systematic classification of NMD events in transcripts.
• To enable the analysis of NMD events in both annotated and de novo assembled transcriptomes.
• To facilitate evolutionary and regulatory studies of NMD by comparing NMD events across different conditions or species.

Main Methods:

• NMD Classifier employs a principle of minimal evolutionary or regulatory change, assuming the least altered event is the most probable.
• The tool analyzes transcript structures to identify NMD-inducing alterations.
• Simulations were used to validate the performance and accuracy of NMD Classifier.

Main Results:

• NMD Classifier demonstrated high accuracy in identifying NMD-causing transcript structural changes.
• The tool correctly identified an average of 99.3% of simulated NMD events.
• Key structural changes accurately identified include exon inclusions/exclusions and alterations in exon boundaries.

Conclusions:

• NMD Classifier provides a robust method for classifying NMD events in transcriptomes.
• The tool's high accuracy and efficiency support its application in large-scale evolutionary and regulatory analyses of NMD.
• NMD Classifier will aid researchers in investigating the complex roles of NMD in gene regulation and evolution across diverse organisms.