Affinage · Plasmodium

PF3D7_0316800

40S ribosomal protein S15A, putative

Annotated
2026-09-07
4 papers in source corpus 3 papers cited in narrative 3 extracted findings

Mechanistic narrative

Synthesis pass · prose summary of the discoveries below

PF3D7_0316800 (S15A) is a constituent protein of the small (40S) subunit of the Plasmodium falciparum 80S ribosome, established through successive structural studies of the native malarial ribosome (PMID:24913268, PMID:40825879). It is resolved as a component of the 40S subunit in cryo-EM reconstructions of the intact 80S ribosome, including structures capturing emetine bound at the small-subunit E-site where it blocks mRNA/tRNA translocation (PMID:24913268), and in reconstructions from blood-stage schizonts that distinguish the parasite ribosome from its mammalian counterpart (PMID:26432834). In situ cryo-electron tomography of infected erythrocytes further places the 40S subunit, and thus S15A, within the native cellular context of actively translating ribosomes during elongation (PMID:40825879). Beyond its membership in the 40S small subunit, no experiment in the available corpus defines a specific mechanistic role, interaction, or individual function for S15A itself.

Mechanistic history

Synthesis pass · year-by-year structured walk · 3 steps
  1. 2014 Medium

    Whether the P. falciparum 40S small subunit and its components could be resolved in structural detail was unknown; a high-resolution cryo-EM structure of the 80S ribosome placed S15A within the small subunit and revealed how the antimalarial emetine blocks translocation at the small-subunit E-site.

    Evidence Cryo-EM structure determination of the intact Pf80S ribosome at 3.2 Å resolution with bound emetine

    PMID:24913268

    Open questions at the time
    • Does not probe S15A's individual contribution to subunit assembly or translation
    • No functional perturbation of S15A
    • No S15A-specific interactions defined
  2. 2015 Medium

    It was unclear how the parasite ribosome differs structurally and dynamically from the mammalian ribosome; sub-nanometer cryo-EM of schizont-purified ribosomes with flexible-fitted atomic models resolved distinguishing features of the small subunit that contains S15A.

    Evidence Cryo-EM reconstructions with flexible-fitting atomic model building from blood-stage schizont-purified ribosomes

    PMID:26432834

    Open questions at the time
    • No S15A-specific functional role interrogated
    • Dynamics attributed to the subunit as a whole, not S15A individually
  3. 2025 Medium

    Whether the malarial ribosome's translating states could be observed in the native cellular environment was unresolved; in situ cryo-electron tomography captured eight structures of actively translating ribosomes, situating the 40S subunit containing S15A within elongation in infected erythrocytes.

    Evidence In situ cryo-electron tomography in P. falciparum-infected erythrocytes yielding eight high-resolution structures of the native ribosome in translating states

    PMID:40825879

    Open questions at the time
    • Does not isolate S15A's role in the native ribosome
    • No functional or knockdown data for S15A

Open questions

Synthesis pass · forward-looking unresolved questions
  • It remains unknown whether S15A has any function beyond structural membership in the 40S subunit — its individual contribution to subunit assembly, translation fidelity, essentiality, or any regulatory role in P. falciparum has not been experimentally defined.
  • No genetic perturbation of S15A
  • No S15A-specific interaction or substrate data
  • No S15A-specific phenotype established

Mechanism profile

Synthesis pass · controlled-vocabulary classification
Complex memberships
40S small ribosomal subunit of the P. falciparum 80S ribosome

Evidence

Reading pass · 3 per-paper findings extracted from the source corpus
Year Finding Method Journal Conf PMIDs
2014 Cryo-EM structure of the P. falciparum 80S ribosome at 3.2 Å resolution revealed the structural context of the small (40S) ribosomal subunit, of which S15A (PF3D7_0316800) is a component, bound to emetine at the E-site; the structure established that emetine blocks mRNA/tRNA translocation by binding the small subunit E-site. Cryo-EM structure determination at 3.2 Å resolution eLife Medium 24913268
2015 Cryo-EM reconstructions of P. falciparum 80S ribosomes purified from blood-stage schizonts at sub-nanometer resolution, with atomic models built by flexible fitting, revealed structural and dynamic features of the ribosome (including the 40S small subunit, of which S15A/PF3D7_0316800 is a component) that differentiate it from mammalian ribosomes. Cryo-EM with multiple reconstructions and flexible-fitting atomic model building from schizont-purified ribosomes Nucleic acids research Medium 26432834
2025 In situ cryo-electron tomography of P. falciparum-infected erythrocytes determined eight high-resolution structures of the native malarial ribosome in actively translating states, establishing the structural environment of the 40S small subunit (of which S15A/PF3D7_0316800 is a constituent) within the native cellular context during translation elongation. In situ cryo-electron tomography in P. falciparum-infected erythrocytes; eight high-resolution structures of the native ribosome in translating states Nature structural & molecular biology Medium 40825879

Source papers

Stage 0 corpus · 4 papers · ranked by NIH iCite citations
Year Title Journal Citations PMID
2014 Cryo-EM structure of the Plasmodium falciparum 80S ribosome bound to the anti-protozoan drug emetine. eLife 272 24913268
2015 Dynamical features of the Plasmodium falciparum ribosome during translation. Nucleic acids research 45 26432834
2025 Integrated structural biology of the native malarial translation machinery and its inhibition by an antimalarial drug. Nature structural & molecular biology 7 40825879
2025 Antimalarial drug artemisinin stabilizes PfRACK1 binding to the ribosome. Structure (London, England : 1993) 3 40480224