SNU13

PF3D7_1123900 (SNU13) is a nuclear protein of Plasmodium falciparum identified in the experimentally determined core nuclear proteome by high-accuracy mass spectrometry, where network analysis positioned it as a central node bridging clusters assigned to mRNA splicing/processing, the nucleolus, and translation initiation (PMID:23181666). Beyond this localization and network placement, no direct biochemical or functional experiment has been performed on the P. falciparum protein itself; its assignment as a box C/D snoRNP component (with fibrillarin, Nop56, and Nop58) rests on computational homology rather than experiment (PMID:19200392), and its detection as a proximity interactor of PfSAMS and PfSET10 comes from single proximity-labeling screens with bioinformatic network interpretation (PMID:35889137, PMID:39445823). The corpus therefore establishes SNU13 as a nuclear, network-central protein linked by inference to spliceosomal, ribosome-biogenesis, and translation-associated machinery, but no molecular activity of PF3D7_1123900 has been directly demonstrated.

1. 2009 Low

   To ask whether malaria parasites possess the conserved rRNA-modification machinery, a homology search tested whether a SNU13 homologue exists as part of the box C/D snoRNP.

   Evidence Computational PSI-BLAST homology search across Plasmodium genomes

   PMID:19200392

   Open questions at the time

   • Purely computational prediction with no biochemical validation on the Plasmodium protein
   • snoRNP membership and rRNA 2'-O-methylation role not experimentally confirmed for PF3D7_1123900
   • No demonstration of physical association with fibrillarin, Nop56, or Nop58 in the parasite
2. 2012 Medium

   To establish where PF3D7_1123900 acts, nuclear proteomics placed it experimentally in the core nuclear proteome and network analysis identified it as a hub connecting splicing/processing, nucleolar, and translation-initiation clusters.

   Evidence High-accuracy mass spectrometry of nuclear fractions with STRING network analysis in P. falciparum

   PMID:23181666

   Open questions at the time

   • Network centrality is bioinformatic inference, not a functional assay
   • No direct molecular activity assigned to the protein
   • Does not distinguish which of the linked processes SNU13 directly participates in
3. 2022 Low

   A proximity-labeling screen around PfSAMS tested SNU13's local environment and placed it as an intermediary linking the spliceosome cluster to translation initiation factors.

   Evidence BioID/TurboID proximity labeling coupled to mass spectrometry with STRING network analysis in blood-stage parasites

   PMID:35889137

   Open questions at the time

   • Single proximity-labeling experiment; proximity does not establish a direct or functional interaction
   • Network role is bioinformatic inference
   • No reciprocal validation of the PfSAMS association
4. 2024 Low

   A TurboID screen around PfSET10 again recovered SNU13, reinforcing its network position bridging mRNA processing, ribosomes/translation, and spliceosome clusters.

   Evidence TurboID proximity labeling coupled to mass spectrometry with STRING network analysis in blood-stage parasites

   PMID:39445823

   Open questions at the time

   • Single proximity-labeling experiment in one lab
   • Network centrality is bioinformatic, not functional
   • Does not establish a direct SNU13–PfSET10 interaction or a shared pathway

• No direct biochemical or functional experiment has defined the molecular activity, RNA/protein partners, or in vivo role of PF3D7_1123900 itself; whether it functions in box C/D snoRNP-mediated rRNA methylation, spliceosome assembly, or translation remains experimentally unresolved.
• No knockout, knockdown, or complementation phenotype for PF3D7_1123900
• No demonstrated RNA-binding or snoRNP assembly activity in the parasite
• No structural or reconstitution data on the P. falciparum protein