Affinage · Plasmodium

PF3D7_1317800

40S ribosomal protein S19

Annotated
2026-09-08
4 papers in source corpus 3 papers cited in narrative 3 extracted findings

Mechanistic narrative

Synthesis pass · prose summary of the discoveries below

PF3D7_1317800 (S19) is established solely as a structural component of the small (40S) subunit of the Plasmodium falciparum 80S ribosome, as visualized in high-resolution cryo-EM and in situ cryo-ET structures (PMID:24913268, PMID:40825879). Its assignment to the 40S subunit was made in the 3.2 Å cryo-EM structure of the P. falciparum 80S ribosome bound to emetine (PMID:24913268), confirmed in sub-nanometer reconstructions of blood-stage ribosomes whose atomic models revealed features distinguishing the malarial ribosome from its mammalian counterpart (PMID:26432834), and further placed within actively translating native ribosomes inside infected erythrocytes by in situ cryo-ET (PMID:40825879). No catalytic, binding, or regulatory activity unique to S19 itself has been characterized in the available corpus; every finding derives from whole-ribosome structural studies in which S19 is one of many resolved subunit components.

Mechanistic history

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

    Establishing where S19 resides within the malarial translation machinery required a high-resolution ribosome structure; the 80S cryo-EM structure placed S19 as a constituent of the 40S small subunit.

    Evidence Cryo-EM at 3.2 Å of the P. falciparum 80S ribosome in complex with emetine

    PMID:24913268

    Open questions at the time
    • No functional or structural role specific to S19 is defined beyond 40S membership
    • The emetine-binding site characterized is on the small subunit generally, not attributed to S19
    • No interaction partners or contacts of S19 with rRNA or other proteins are described
  2. 2015 Medium

    Whether the malarial 40S differs structurally from the mammalian ribosome was addressed by additional reconstructions that confirmed S19 as a 40S component and revealed parasite-specific ribosome features.

    Evidence Cryo-EM with multiple sub-nanometer reconstructions and flexible-fitting atomic models of blood-stage 80S ribosomes

    PMID:26432834

    Open questions at the time
    • Parasite-specific features are attributed to the ribosome as a whole, not to S19 individually
    • No unique role of S19 in the divergent features is established
  3. 2025 Medium

    Whether S19 assignments from purified-ribosome structures hold in the native cellular context was tested by in situ cryo-ET of translating ribosomes, confirming S19 in the 40S subunit within infected erythrocytes.

    Evidence In situ cryo-electron tomography resolving eight high-resolution states of the native malarial ribosome inside infected erythrocytes

    PMID:40825879

    Open questions at the time
    • No S19-specific role in the translation states or ribosome biogenesis response is defined
    • The inhibitor effect on elongation-factor-bound states is a whole-ribosome observation, not linked to S19

Open questions

Synthesis pass · forward-looking unresolved questions
  • Whether S19 possesses any function beyond its structural membership in the 40S subunit — a specific contact, regulatory role, or extraribosomal activity — remains uncharacterized in the available corpus.
  • No experiment isolates or perturbs S19 specifically
  • No binding partners, substrates, or regulatory functions of S19 are reported
  • No genetic or biochemical study of S19 apart from whole-ribosome structures exists in the corpus

Mechanism profile

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

Evidence

Reading pass · 3 per-paper findings extracted from the source corpus
Year Finding Method Journal Conf PMIDs
2014 The cryo-EM structure of the P. falciparum 80S ribosome at 3.2 Å resolution places S19 (PF3D7_1317800) as a component of the small (40S) ribosomal subunit; the structure shows emetine binding at the E-site of the small subunit and blocking mRNA/tRNA translocation, establishing the structural context in which S19 resides. Cryo-EM structure determination at 3.2 Å resolution of the P. falciparum 80S ribosome in complex with emetine eLife Medium 24913268
2015 Sub-nanometer cryo-EM reconstructions of blood-stage P. falciparum 80S ribosomes confirm that S19 (PF3D7_1317800) is part of the 40S small subunit; atomic models built by flexible fitting reveal structural and dynamic features of the P. falciparum ribosome that differentiate it from the mammalian ribosome. Cryo-EM with multiple reconstructions at sub-nanometer resolution and flexible-fitting atomic model building Nucleic acids research Medium 26432834
2025 In situ cryo-electron tomography of actively translating ribosomes inside P. falciparum-infected erythrocytes resolves eight high-resolution structures of the native malarial ribosome; S19 (PF3D7_1317800) is confirmed as a component of the 40S subunit within the cellular context, and the study shows that a Plasmodium-specific translation inhibitor decreases elongation factor-bound ribosomal states and apparently upregulates ribosome biogenesis. In situ cryo-electron tomography with high-resolution structure determination inside infected erythrocytes 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