PF3D7_1119800

PF3D7_1119800 (PfASF-1) is annotated as a plasmodial alternative splicing factor in Plasmodium falciparum, and the available corpus characterizes it primarily as a phosphorylation substrate within a nuclear splicing regulatory pathway (PMID:21312235). In vitro, recombinant PfASF-1 is phosphorylated by the cyclin-dependent kinase-like kinases PfCLK-1 (a Lammer kinase homolog) and PfCLK-2, establishing these two nuclear CLKs as upstream kinases for PfASF-1 and implying that its activity is regulated post-translationally (PMID:21312235). Beyond this kinase-substrate relationship, no direct RNA targets, splicing activity, phosphorylation sites, interaction partners, or cellular phenotypes have been characterized for PF3D7_1119800 in the available corpus.

1. 2011 Medium

   To determine whether the alternative splicing factor PfASF-1 is subject to post-translational control, this work asked which kinases act on it and showed that the nuclear CLK-family kinases PfCLK-1 and PfCLK-2 phosphorylate it in vitro, placing PfASF-1 downstream of CLK signaling in a putative splicing regulatory pathway.

   Evidence In vitro kinase assay with recombinant PfCLK-1 and PfCLK-2 using PfASF-1 as substrate

   PMID:21312235

   Open questions at the time

   • Phosphorylation sites on PfASF-1 were not mapped by mutagenesis
   • Functional consequence of phosphorylation for splicing activity is not established
   • Interaction and phosphorylation shown in vitro only, not confirmed in the parasite

• It remains unknown what RNA targets PfASF-1 acts on, whether it participates in a defined spliceosomal complex, and what phenotype results from disrupting it or its phosphorylation in blood-stage parasites.
• No splicing substrate or RNA target identified for PfASF-1
• No stable interaction partners or complex membership established
• No genetic knockout or knockdown phenotype reported