Splice up your life: an iron-regulated factor in Toxoplasma gondii!

Abstract

Toxoplasma gondii is an alveolate belonging to the pathogenically renowned phylum, Apicomplexa and the causative agent of toxoplasmosis. Being an intracellular pathogen, the parasite must contend with the host’s dynamic nutrient availability through transcriptional and post-transcriptional processes. Though not entirely understood, expression of a serine/arginine-rich (SR) factor, dubbed TgSR4i, was discovered to have an abundance of transcripts in tachyzoites cultured in iron chelated environment. This study aims to reveal the genomic and phenotypic influence on parasite survival when TgSR4i is ablated in different iron concentrations. Replication and plaque assays affirmed a stun in the growth of TgSR4i knock out line when cultured in iron chelation, as opposed to iron supplementation. The results of RNA-sequencing analysis marked differentially expression genes associated with the electron transport chain and DNA metabolism under iron deprivation and no pathway enrichment of hetero-lactic fermentation, as opposed to untreated parasites. Additionally, 11 genes were spliced, most exhibiting intron retention. Further investigation into TgSR4i could expand our knowledge about the parasite’s iron metabolism and use it as a potential drug target.