Trypanosoma cruzi DM28c Transcriptome or Gene expression

Due to the absence of transcription regulation of protein coding genes transcribed by RNA polymerase II, post transcriptional regulation is responsible for the majority of gene expression changes in trypanosomatids. Therefore, cataloging the abundance of mRNAs (transcriptome) and the level of their translation (translatome) is a key factor to understand control of gene expression in these organisms. Here we assess the extent of regulation of transcription and translation in the Chagas disease causing agent, Trypanosoma cruzi, at both the non-infective (epimastigote) and infective (metacyclic trypomastigote) life stages using RNA-seq and ribosome profiling. The observed steady state transcript levels support pervasive transcription and maturation implying the existence of distinctive post transcriptional regulatory mechanisms acting at those parasite stages. Meanwhile, the down regulation of a large proportion of the translatome indicates a key role of translation control in differential gene expression. The previously described proteomic data correlate better with the translatomes than with the transcriptomes and translational efficiency analysis shows a wide dynamic range, reinforcing the importance of translatability as a regulatory step. Efficiencies for protein families like ribosomal components are diminished while translation of the transialidase virulence factors is up regulated in the quiescent infective metacyclic trypomastigote stage. Globally this study highlights translational regulation as a major factor during the parasite differentiation.