Mutant/mutation
The mutant lacks expression of tRIP and expresses mCherry (promoter unknown)

Protein (function)
A widely distributed tRNA binding motif is exemplified by a minimal tRNA binding protein—Trbp111—that was first identified in Aquifex aeolicus. This free-standing homodimeric protein specifically binds tRNA by recognizing its characteristic elbow structure. Other proteins that contain this motif include the yeast aminoacyl-tRNA synthetase cofactor 1 (ARC1p), the metazoan AIMP1, and Toxoplasma gondii Tg-p43 aminoacyl-tRNA synthetase interacting proteins. The PF3D7_1442300 gene encodes a 402-amino-acid with a Trbp111-orthologous domain at its C terminus and an N-terminal region exhibiting a transmembrane helix motif.

Phenotype
(Slightly) reduced growth/multiplication of asexual blood stages

Additional information
Evidence is presented that tRip (tRNA import protein)—is anchored to the parasite plasma membrane and directs import of exogenous tRNAs. In the absence of tRip, the fitness of the parasite stage that multiplies in the blood is  reduced, indicating that the parasite may need host tRNAs to sustain its own translation and/or as regulatory RNAs.

Evidence is presented for a surface/plasma membrane location of tRIP in merozoites and sporozoites.

In Plasmodium, the causative agent of malaria, the nuclear genome has a minimal set of 45 transfer RNA (tRNA) genes, with only one gene per tRNA isoacceptor. This single-gene feature is an exception among eukaryotes, where tRNA genes are usually present in multiple copies. Discrepancies between codon use and expression levels of corresponding tRNAs were also observed in Plasmodium falciparum blood stages. These considerations raise the possibility that, under at least some conditions, the parasite may need an additional source of tRNAs and possibly rely on the import of exogenous tRNAs.

Other mutants