EIF3M

PF3D7_0418200 (EIF3M), a putative eukaryotic translation initiation factor 3 subunit of Plasmodium falciparum, is defined in the available corpus principally by its association with translationally repressed mRNP complexes during blood-stage development (PMID:38702310). It was identified as a component of stress granule-like mRNPs that assemble in nutritionally stressed schizonts, co-purifying with PfDOZI, PABP2, CITH, PAIP1, and the eIF2B complex; notably, it is absent from the PfDOZI-associated granules of gametocytes, indicating stage-specific incorporation into distinct mRNP assemblies (PMID:38702310). EIF3M also carries phosphorylation and 2-hydroxyisobutyrylation marks detected in blood-stage parasites (PMID:33517144). Beyond this complex membership and the presence of these post-translational modifications, no writers, erasers, functional consequences, or independent biochemical activity of PF3D7_0418200 has been characterized in the available corpus.

1. 2020 Low

   Establishing that PF3D7_0418200 is a modified protein during the intraerythrocytic cycle raised the question of whether its function is regulated post-translationally, providing the first molecular handle on the protein.

   Evidence Mass spectrometry-based proteome-wide PTM mapping across intraerythrocytic developmental stages in P. falciparum

   PMID:33517144

   Open questions at the time

   • No writers, erasers, or readers of the phosphorylation or 2-hydroxyisobutyrylation marks were identified for EIF3M
   • No functional consequence of the modifications was tested
   • Single large-scale proteomics screen without targeted validation
2. 2024 Medium

   Placing PF3D7_0418200 within stress granule-like mRNPs answered where the protein acts, linking it to translational repression machinery under nutritional stress and revealing stage-specific complex composition.

   Evidence Co-immunoprecipitation / quantitative interactome proteomics of PfDOZI under stress conditions in P. falciparum schizonts and gametocytes

   PMID:38702310

   Open questions at the time

   • EIF3M was detected as a component but not individually validated by reciprocal pull-down or mutagenesis
   • Whether EIF3M is required for mRNP assembly, stability, or translational repression is unknown
   • The molecular basis for its exclusion from gametocyte PfDOZI granules is not resolved

• Whether PF3D7_0418200 performs a canonical eIF3-type translation initiation function, or acts primarily as a stress-responsive mRNP component, remains unresolved.
• No direct assay of translation initiation activity for EIF3M
• No genetic knockout or knockdown phenotype reported
• No structural or reciprocal biochemical validation of its complex associations