The cell cycle regulated transcriptome of Trypanosoma brucei

Area of Science:

• Molecular Biology
• Parasitology
• Genomics

Background:

• Eukaryotic cell cycle progression depends on precise gene expression timing.
• Kinetoplastids, including pathogens like Trypanosoma brucei, largely lack transcriptional regulation, posing questions about their cell cycle control.
• Understanding cell cycle regulation in kinetoplastids is crucial for developing anti-parasitic strategies.

Purpose of the Study:

• To investigate gene expression dynamics throughout the Trypanosoma brucei cell cycle.
• To identify mechanisms of cell cycle regulation in kinetoplastids.
• To explore the role of post-transcriptional regulation in kinetoplastid proliferation.

Main Methods:

• Developed a "double-cut" elutriation method for highly synchronous Trypanosoma brucei cell populations.
• Performed transcriptome-wide mRNA abundance profiling across the cell cycle.
• Analyzed sequence motifs in co-regulated transcripts for conserved regulatory elements.

Main Results:

• Identified regulation of at least 430 genes during the Trypanosoma brucei cell cycle.
• Discovered conserved RNA sequence motifs, potentially bound by RNA-binding proteins, in co-regulated gene groups.
• Found evidence for cell-cycle regulation of a flagellar protein regulon involving conserved motifs similar to PUF-protein binding sites.

Conclusions:

• Post-transcriptional regulation, mediated by conserved RNA sequence motifs, is central to cell cycle control and proliferation in parasitic kinetoplastids.
• These regulatory mechanisms are more widespread and conserved within kinetoplastids than previously understood.
• Findings challenge traditional models of cell cycle regulation and highlight novel therapeutic targets.