Alternative splicing drives a dynamic transcriptomic response during Acanthamoeba castellanii programmed cell death.

Area of Science:

• Cell Biology
• Molecular Biology
• Genomics

Background:

• Programmed cell death (PCD) is crucial for multicellular organisms but less understood in unicellular eukaryotes.
• Acanthamoeba castellanii, a facultative human pathogen, offers a model for studying PCD in unicellular organisms.

Purpose of the Study:

• To investigate the transcriptomic and alternative splicing (AS) responses of Acanthamoeba castellanii during G418-induced PCD.
• To elucidate the role of AS, specifically intron retention (IR), in regulating PCD in this amoeba.

Main Methods:

• RNA sequencing was employed to analyze global gene expression changes over six hours of G418 treatment.
• Differential splicing events were identified and characterized, with a focus on intron retention patterns.
• Correlational analyses were performed to link IR with transcript levels.

Main Results:

• Approximately 70% of annotated genes showed transcriptional changes during PCD.
• 18,748 differentially spliced events were detected, with intron retention being the predominant type.
• A shift in retained intron distribution from 3' bias to uniform was observed during PCD, negatively correlating with transcript levels.

Conclusions:

• Alternative splicing, especially intron retention, plays a significant regulatory role in Acanthamoeba castellanii PCD.
• The dynamic positional shift of retained introns suggests a novel mechanism controlling gene expression during PCD.
• Findings enhance understanding of PCD in unicellular organisms and may reveal therapeutic targets related to Acanthamoeba infections.