PTB

PF3D7_0606500 (PTB) is annotated by phylogenetic and bioinformatic analysis as the single polypyrimidine tract-binding protein orthologue in Plasmodium falciparum (PMID:30782661). The only experimental evidence linking it to a cellular process is its co-purification with the PfPRMT5-associated protein complex, placing it within the RNA splicing machinery implicated in alternative splicing regulation (PMID:37349497). Beyond this complex membership, no direct functional or mechanistic characterization of PF3D7_0606500 itself — its RNA targets, splicing activity, localization, or phenotype — has been reported in the available corpus.

1. 2019 Low

   Establishing whether P. falciparum encodes a PTB orthologue was the first step toward asking whether polypyrimidine-tract-based splicing regulation operates in the parasite; bioinformatics identified PF3D7_0606500 as the sole such orthologue.

   Evidence Phylogenetic analysis and bioinformatic annotation, with TGME49_090660 identified as the T. gondii counterpart

   PMID:30782661

   Open questions at the time

   • Computational identification only; no experimental confirmation of PTB activity in Plasmodium
   • No RNA-binding or splicing function demonstrated for the parasite protein
   • No expression, localization, or essentiality data
2. 2023 Low

   The question of whether PF3D7_0606500 physically associates with splicing machinery was addressed by finding it among proteins co-purifying with PfPRMT5, placing it in a complex regulating alternative splicing.

   Evidence Co-immunoprecipitation / interactome mass spectrometry of cytosolic and nuclear PfPRMT5 pulldowns

   PMID:37349497

   Open questions at the time

   • Single Co-IP/MS experiment identifying PTB as one of many co-purifying proteins, with no reciprocal validation or functional follow-up on PTB itself
   • Direct RNA targets and splicing role of PF3D7_0606500 not defined
   • Whether the association is direct or bridged by other complex members is unknown

• The intrinsic molecular function of PF3D7_0606500 — its RNA-binding specificity, splicing substrates, subcellular localization, and requirement for parasite viability — remains uncharacterized.
• No demonstrated polypyrimidine-tract or RNA binding by the Plasmodium protein
• No identified splicing targets or regulatory outcomes
• No knockout, knockdown, or phenotypic data