Two aminoacyl-tRNA synthetase complexes anchored to the Plasmodium surface tRNA import protein

ABSTRACT: Aminoacyl-tRNA synthetases (aaRSs) attach amino acids to their cognate transfer RNAs. In eukaryotes, a subset of cytosolic aaRSs is organized into a multi-synthetase complex (MSC), along with specialized scaffolding proteins referred to as aaRS-interacting multifunctional proteins (AIMPs). In Plasmodium, the causative agent of malaria, the tRNA import protein (tRip), is a membrane protein which participates in tRNA trafficking. Here, we show that tRip is also an AIMP. We identified three aaRSs, namely the glutamyl- (ERS), glutaminyl- (QRS), and methionyl- (MRS) tRNA synthetases, which were specifically co-immunoprecipitated with tRip in Plasmodium berghei blood stage parasites. All four proteins contain an N-terminal GST-like domain involved in MSC assembly. Surprisingly, further dissection of GST-like interactions identified two exclusive heterotrimeric complexes: Q-complex (tRip:ERS:QRS) and M-complex (tRip:ERS:MRS). Gel filtration and light scattering suggest a 2:2:2 stoichiometry for both complexes but with distinct biophysical properties and mutational analysis revealed that the GST-like domains of QRS and MRS use different strategies to bind ERS. Furthermore, the modular organization of the assembled aaRSs and the properties of the specific additional modules supported the proposed localization of these complexes at the parasite membrane.

INSTRUMENT(S): TripleTOF 5600, Q Exactive

ORGANISM(S): Escherichia Coli Mus Musculus (mouse)

TISSUE(S): Blood

DISEASE(S): Plasmodium Falciparum Malaria

SUBMITTER: Johana Chicher  

LAB HEAD: Magali Frugier

PROVIDER: PXD033057 | Pride | 2022-06-09

REPOSITORIES: Pride