Identification and characterization of alternative splicing in parasitic nematode transcriptomes

Area of Science:

• Genomics
• Molecular Biology
• Parasitology

Background:

• Alternative splicing (AS) enhances eukaryotic genomic complexity, producing diverse protein isoforms.
• AS is crucial for understanding parasitic nematodes with complex life cycles.
• Existing transcriptomic data requires splice-aware assembly for helminth AS studies.

Purpose of the Study:

• To develop and optimize splice-aware assembly protocols for analyzing alternative splicing in parasitic nematodes.
• To conduct the first comprehensive survey of alternative splicing across multiple parasitic nematode species.

Main Methods:

• cDNA sequencing of Caenorhabditis elegans using 454/Roche technology.
• Assembly of sequencing reads using Newbler software with optimized parameters.
• Validation of assembled transcripts against known C. elegans genes and Illumina RNAseq data.

Main Results:

• Optimized assembly parameters improved transcript matching, reduced mis-assemblies, and enhanced gene coverage.
• Alternative splicing rates of 20-30% with 2-3 transcripts per locus were observed in nine parasitic nematode species.
• 21 InterPro domains, including those for nucleotide and chromatin binding, were correlated with AS loci.

Conclusions:

• Optimized assembly parameters enabled the first survey of alternative splicing in parasitic nematodes.
• Generated transcriptome assemblies, protein translations, and annotations are publicly available on Nematode.net.
• These resources will aid research on specific genes, gene families, and genome assembly curation.