Five-layer systems analysis of Leishmania stage differentiation reveals an essential role for protein degradation in parasite development.

Proteasomal activity is essential for Leishmania donovani stage differentiation, with proteasome inhibition impairing parasite development and revealing key regulatory mechanisms.

• Why it matters: Understanding how Leishmania transitions between insect and mammalian stages is crucial for developing targeted interventions against leishmaniasis, yet the molecular drivers of this process remain poorly characterized.
• What they did: A five-layer integrative systems analysis compared hamster-derived amastigotes and culture-derived promastigotes, focusing on gene expression, protein abundance, and degradation, including proteasome inhibition experiments.
• The result: Differential protein degradation, particularly via the proteasome, was identified as a major factor in stage-specific regulation, providing insights into post-transcriptional control and offering a blueprint for studying similar transitions in other pathogens.