A divergent nonsense-mediated decay machinery in Plasmodium falciparum is inefficient and non-essential

Abstract

ABSTRACT Nonsense-mediated decay (NMD) is a conserved mRNA quality control process that eliminates transcripts bearing a premature termination codon. In addition to its role in removing erroneous transcripts, NMD is involved in post-transcriptional regulation of gene expression via programmed intron retention in metazoans. The apicomplexan parasite Plasmodium falciparum shows relatively high levels of intron retention, but it is unclear whether these variant transcripts are functional targets of NMD. In this study, we use CRISPR-Cas9 to disrupt and epitope-tag two core NMD components: Pf UPF1 (PF3D7_1005500) and Pf UPF2 (PF3D7_0925800). Using RNA-seq, we find that NMD in P. falciparum is hig..