Analyses of the essential C82 subunit uncover some differences in RNA polymerase III transcription between Trypanosoma brucei and Leishmania major
Ontology highlight
ABSTRACT: The 17-subunit RNA polymerase III (RNAP III) synthesizes essential untranslated RNAs such as tRNAs and 5S rRNA. In yeast and vertebrates, subunit C82 forms a stable subcomplex with C34 and C31 that is necessary for promoter-specific transcription initiation. Little is known about RNAP III transcription in trypanosomatid parasites. To narrow this knowledge gap, we characterized the C82 subunit in Trypanosoma brucei and Leishmania major. Bioinformatic analyses showed that the four distinctive winged-helix domains and the coiled-coil motif are present in C82 in these microorganisms, despite the observation of certain unique traits. Also, their projected three-dimensional structure is comparable to that of the human orthologue. C82 localizes to the nucleus and binds to RNAP III-dependent genes in the insect stages of both parasites. In T. brucei, knock-down of C82 by RNA interference significantly reduced the levels of tRNAs and 5S rRNA and led to the death of procyclic forms of the pathogen. Tandem affinity purifications with both parasites allowed the identification of several C82-interacting partners, including C34 and some genus-specific putative regulators of transcription. However, the orthologue of C31 was not found in trypanosomatids. Interestingly, our data suggest a strong association of C82 with TFIIIC subunits in T. brucei, but not in L. major.
INSTRUMENT(S): Orbitrap Fusion Lumos
ORGANISM(S): Trypanosoma Brucei Leishmania Major Strain Friedlin
TISSUE(S): Cell Culture
SUBMITTER: Ebbing de Jong
LAB HEAD: Santiago Martínez-Calvillo
PROVIDER: PXD051017 | Pride | 2024-11-13
REPOSITORIES: Pride
ACCESS DATA