The role of tRNAs in translation makes them essential for every living organism. The first tRNA modification was discovered in 1965 and since then, the number of modifications has increased to reach more than 100 different chemistries. Our research project focus on a doubly modified uridine positioned at the wobble position of three tRNAs within the anticodon stem loop. This complex double modification is the 5-methoxycarbonylmethyl-2-thiouridine at position 34 (mcm5s2U34). A plethora of proteins is required for the synthesis of mcm5s2U34. Among them, Elongator is a conserved, 6-subunits complex (Elp1-6), which takes part in the synthesis of the cm5 moiety of the modification. Recent studies have highlighted the critical role of Elongator in several diseases, mainly linked with brain development. However, Elongator is also required for tumorigenesis, especially in the case of melanoma, breast cancers and Wnt-dependent tumour initiation. Our research aims at performing a molecular screen to isolate compounds acting as Elongator inhibitors with the hope to treat the associated cancers. The screening strategy relies on the ability of the Kluyveromyces lactis toxin, zymocin, to cleave mcm5s2U34 modified tRNAs, which led to cell death, while unmodified tRNAs are unaffected. Our goal is to construct a strain of Schizosaccharomyces pombe expressing the human Elongator complex together with the zymocin catalytic subunit under the control of an inducible promoter. Compounds providing resistance to induction of the toxin will be further characterized as they likely target the synthesis of the modification.
|Date of Award||18 Jan 2021|
|Supervisor||Damien Hermand (Supervisor)|