Proteome remodelling during development from blood to insect-form Trypanosoma brucei quantified by SILAC and mass spectrometry

TL;DR

This study provides a comprehensive comparison of protein levels across three life stages of Trypanosoma brucei using SILAC and mass spectrometry, revealing insights into proteome remodeling and regulation mechanisms during development.

Contribution

First comprehensive proteomic analysis of T. brucei's three life stages, highlighting stage-specific protein abundance and regulatory mechanisms.

Findings

Identified over 1600 proteins, covering ~30% of the proteome.

Detected pre-adaptation in short stumpy cells, especially mitochondrial proteins.

Moderate correlation between mRNA and protein levels suggests complex regulation.

Abstract

Background: Trypanosoma brucei is the causative agent of human African sleeping sickness and Nagana in cattle. In addition to being an important pathogen T. brucei has developed into a model system in cell biology. Results: Using Stable Isotope Labelling of Amino acids in Cell culture (SILAC) in combination with mass spectrometry we determined the abundance of >1600 proteins in the long slender (LS), short stumpy (SS) mammalian bloodstream form stages relative to the procyclic (PC) insect-form stage. In total we identified 2645 proteins, corresponding to ~30% of the total proteome and for the first time present a comprehensive overview of relative protein levels in three life stages of the parasite. Conclusions: We can show the extent of pre-adaptation in the SS cells, especially at the level of the mitochondrial proteome. The comparison to a previously published report on monomorphic in vitro grown bloodstream and procyclic T. brucei indicates a loss of stringent regulation particularly of mitochondrial proteins in these cells when compared to the pleomorphic in vivo situation. In order to better understand the different levels of gene expression regulation in this organism we compared mRNA steady state abundance with the relative protein abundance-changes and detected moderate but significant correlation indicating that trypanosomes possess a significant repertoire of translational and posttranslational mechanisms to regulate protein abundance.