Project description:Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease with limited effective treatment options, potentiating the importance of uncovering novel drug targets. Here, we target Cleavage and Polyadenylation Specificity Factor 3 (CPSF3), the 3’ endonuclease that catalyzes mRNA cleavage during polyadenylation and histone mRNA processing. We find that CPSF3 is highly expressed in PDAC and is associated with poor prognosis. CPSF3 knockdown blocks PDAC cell proliferation and colony formation in vitro and tumor growth in vivo. Chemical inhibition of CPSF3 by the small molecule JTE-607 also attenuates PDAC cell proliferation and colony formation, while it has no effect on cell proliferation of non-transformed immortalized control pancreatic cells. Mechanistically, JTE-607 induces transcriptional read-through in replication-dependent histones, reduces core histone expression, destabilizes chromatin structure and arrests cells in the S-phase of the cell cycle. Therefore, CPSF3 represents a potential therapeutic target for the treatment of PDAC.
Project description:African trypanosomes cause lethal and neglected tropical diseases, known as sleeping sickness in humans and nagana in animals. Current therapies are limited, but fortunately, promising therapies are in advanced clinical and veterinary development, including acoziborole (AN5568 or SCYX-7158) and AN11736, respectively. These benzoxaboroles will likely be key to the World Health Organization's target of disease control by 2030. Their mode of action was previously unknown. We have developed a high-coverage overexpression library and use it here to explore drug mode of action in Trypanosoma brucei Initially, an inhibitor with a known target was used to select for drug resistance and to test massive parallel library screening and genome-wide mapping; this effectively identified the known target and validated the approach. Subsequently, the overexpression screening approach was used to identify the target of the benzoxaboroles, Cleavage and Polyadenylation Specificity Factor 3 (CPSF3, Tb927.4.1340). We validated the CPSF3 endonuclease as the target, using independent overexpression strains. Knockdown provided genetic validation of CPSF3 as essential, and GFP tagging confirmed the expected nuclear localization. Molecular docking and CRISPR-Cas9-based editing demonstrated how acoziborole can specifically block the active site and mRNA processing by parasite, but not host CPSF3. Thus, our findings provide both genetic and chemical validation for CPSF3 as an important drug target in trypanosomes and reveal inhibition of mRNA maturation as the mode of action of the trypanocidal benzoxaboroles. Understanding the mechanism of action of benzoxaborole-based therapies can assist development of improved therapies, as well as the prediction and monitoring of resistance, if or when it arises.
Project description:Target identification of an antimalarial oxaborole identifies AN13762 as an alternative chemotype for targeting CPSF3 in apicomplexan parasites.
Project description:The roles of 3’-exoribonucleases and the exosome in trypanosome mRNA degradation; 30 min after actinomycin D +sinefungin, RNAi against CAf1, CNOT10, PAN2. These are really old data that hadn't been deposited.The datasets called RNA1, RNA2, RNA3 and RNA4 are almost certainly, from their location in the folder and from new alignment results, from the RRP45 RNAi.
Project description:Tissues were harvested from mice from two congenic strains (Tir1CC and Tir3CC) and their two control strains (Tir1AA and Tir3AA). The congenic strains were bred from inbred lines known to be susceptible (A/J) and tolerant (C57BL/6) to Trypanosome infection, such that C57BL/6 genomic regions underlying QTL for trypanotolerance were present in an A/J genetic background. Liver and spleen tissues were harvested. For each strain RNA was prepared from various tissues of twenty mice. For each condition, RNA extracts from individuals were pooled (5 per pool) prior to hybridisation.
Project description:Glycolysis is the sole free-energy source for the deadly parasite Trypanosoma brucei and is therefore a possible target pathway for anti-trypanosomal drugs. Plasma-membrane glucose transport exerts high control over trypanosome glycolysis and hence the transporter is a promising drug target. Here we show that at high inhibitor concentrations, inhibition of trypanosome glucose transport causes cell death. Most interestingly, sublethal concentrations initiate a domino effect in which network adaptations enhance inhibition.
