sharma, p. | bioRxiv Science

bioRxiv2025

Altiratinib Targets PRP4K in Theileria annulata, Disrupting RNA Processing and Inducing Apoptosis in Infected Cells

Tropical theileriosis, driven by Theileria annulata, poses a critical threat to livestock health, particularly in the face of rising resistance to buparvaquone, the primary and only treatment option. This study investigates the therapeutic potential and mechanistic actions of Altiratinib, a spliceosome-associated kinase inhibitor, in targeting T.annulata-infected bovine cells. Through bioinformatic and molecular docking analyses, Altiratinib was shown to selectively bind conserved catalytic motifs of PRP4K homologs in T. annulata (TA21325) and Theileria parva (TpMuguga_01g00303), with reduced affinity observed upon L715F mutation. In vitro assays confirmed potent anti-parasitic activity against both buparvaquone-sensitive and - resistant strains, while sparing uninfected peripheral blood mononuclear cells. Proteomic profiling revealed disruption of host and parasite RNA splicing and translation machinery. Altiratinib further induced G1-phase arrest, inhibited cMET-mediated signaling, and suppressed DNA synthesis. Additionally, it triggered oxidative stress, mitochondrial depolarization, and ROS-mediated DNA damage, culminating in p53 activation and caspase-9-driven intrinsic apoptosis. Downregulation of TaSP expression reinforced its selective targeting of parasite-infected cells. These findings highlight Altiratinibs promise as a directed therapeutic for tropical theileriosis and other piroplasm infections, offering a novel avenue to combat drug-resistant strains and meriting further preclinical evaluation. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=150 HEIGHT=200 SRC="FIGDIR/small/684341v1_ufig1.gif" ALT="Figure 1"> View larger version (50K): org.highwire.dtl.DTLVardef@eeeb81org.highwire.dtl.DTLVardef@1a795ecorg.highwire.dtl.DTLVardef@163b9cdorg.highwire.dtl.DTLVardef@3b52db_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIAltiratinib disrupts spliceosomal and translational machinery in Theileria annulata-infected host cells by targeting PRP4K homologs, leading to impaired RNA processing, oxidative stress, and intrinsic apoptosis. C_LIO_LIDemonstrates potent efficacy against both drug-sensitive and Buparvaquone-resistant strains, validating its potential as a novel therapeutic strategy for overcoming resistance in tropical theileriosis. C_LIO_LIDual-target mechanism modulates parasite and host oncogenic pathways, including cMET signaling, revealing Altiratinibs repurposing potential as a broad-spectrum antiparasitic with anticancer-like activity. C_LI

microbiology↗

bioRxiv2024

Theileria annulata Infection Promotes p53 suppression, Genomic Instability and DNA deaminase APOBEC3H upregulation leading to cancer-like phenotype in host cells

Theileria annulata-infected host leukocytes display cancer-like phenotypes, though the precise mechanism is yet to be fully understood. The occurrence of cancer-like phenotypes in Theileria-infected leukocytes may be attributed to various factors, including genomic instability and acquired mutations, a crucial trait that underpins the genetic foundation of cancer. This paper presents WGS data and bioinformatic analyses to reveal point mutations and large-scale alterations in six clinically relevant T. annulata-infected cell lines. We identified 7867 exon-linked somatic mutations common to all cell lines, and cancer association analysis showed significant accumulation in oncogenes (FLT4, NOTCH2, MAP3K1, DAXX, FCGR2B, ROS1) and tumor suppressor genes (BARD1, KMT2C, GRIN2A, BAP1) implicated in established critical cancer processes. We demonstrated that a crizotinib-induced blockade of the ROS1 oncogenic protein, which harbored the most mutations, led to the death of infected leukocytes. This is consistent with the significant role of ROS1 in parasite-induced leukocyte transformation. In addition, we found somatic mutations in genes involved in genome instability and the DDR pathway. Our findings support the notion that ROS1 and Nutulin 3a are valid targets for intervention, and the suppression of TP53, a crucial tumor suppressor gene, may play a significant role in cell immortalization. We also show that upon infection with the parasite, bovine cells upregulate the expression of APOBEC3H, a DNA mutator likely responsible for the detected mutations. Our study highlights how T. annulata transforms leukocytes to gain selective advantage via mutation, and our observations could steer future research towards a mechanistic understanding of disease pathogenesis.

cell biology↗