RRP41

PF3D7_1427800 (RRP41) is a catalytically active subunit of the P. falciparum RNA exosome-like complex that degrades single-stranded RNA. Recombinant PfRrp41 exhibits ribonuclease activity against ssRNA in vitro, establishing it as a catalytic component of the parasite exosome-like machinery (PMID:29664138), and the protein localizes to the cytoplasm of asexual-stage parasites (PMID:29664138). Beyond this in vitro activity and localization, no further mechanistic detail — including substrate specificity in vivo, complex partners, or functional consequences of its ribonuclease activity — has been characterized in the available corpus.

1. 2018 Medium

   Whether PF3D7_1427800 is itself an active nuclease or merely a structural exosome subunit was unknown; demonstrating intrinsic ribonuclease activity established it as a catalytic component of the parasite RNA exosome-like complex.

   Evidence In vitro ribonuclease activity assay with recombinant PfRrp41 against ssRNA substrate

   PMID:29664138

   Open questions at the time

   • Activity shown by a single lab with a single method and no catalytic-site mutagenesis to confirm the activity is intrinsic to RRP41
   • Substrate specificity and in vivo RNA targets not defined
   • Contribution to an assembled exosome complex not tested
2. 2018 Medium

   The subcellular compartment in which PF3D7_1427800 operates was unknown; immunofluorescence placed the protein in the cytoplasm of asexual-stage parasites, indicating a cytoplasmic site of exosome-like RNA turnover.

   Evidence Indirect immunofluorescence assay with Western blot confirmation of expression in asexual-stage P. falciparum

   PMID:29664138

   Open questions at the time

   • Localization by indirect IFA in a single lab, not linked to a functional consequence
   • No data on nuclear versus cytoplasmic exosome distribution or stage-specific relocalization
   • Complex assembly state at the localized site not determined

• The identity of the in vivo RNA substrates, the composition of the RRP41-containing exosome-like complex, and the biological role of its ribonuclease activity in parasite biology remain unresolved.
• No interacting exosome subunits or complex partners identified for PF3D7_1427800 in the corpus
• No genetic or knockdown data linking RRP41 activity to a parasite phenotype
• No structural model or catalytic-residue mapping