Use of a Yeast tRNase Killer Toxin to Diagnose Kti12 Motifs Required for tRNA Modification by Elongator

Constance Mehlgarten, Heike Prochaska, Alexander Hammermeister, Wael Abdel-Fattah, Melanie Wagner, Rościsław Krutyhołowa, Sang Eun Jun, Gyung-Tae Kim, Sebastian Glatt, Karin D. Breunig, Michael J R Stark, Raffael Schaffrath (Lead / Corresponding author)

    Research output: Contribution to journalArticlepeer-review

    13 Citations (Scopus)
    288 Downloads (Pure)


    Saccharomyces cerevisiae cells are killed by zymocin, a tRNase ribotoxin complex from Kluyveromyces lactis, which cleaves anticodons and inhibits protein synthesis. Zymocin's action requires specific chemical modification of uridine bases in the anticodon wobble position (U34) by the Elongator complex (Elp1-Elp6). Hence, loss of anticodon modification in mutants lacking Elongator or related KTI (K. lactis Toxin Insensitive) genes protects against tRNA cleavage and confers resistance to the toxin. Here, we show that zymocin can be used as a tool to genetically analyse KTI12, a gene previously shown to code for an Elongator partner protein. From a kti12 mutant pool of zymocin survivors, we identify motifs in Kti12 that are functionally directly coupled to Elongator activity. In addition, shared requirement of U34 modifications for nonsense and missense tRNA suppression (SUP4; SOE1) strongly suggests that Kti12 and Elongator cooperate to assure proper tRNA functioning. We show that the Kti12 motifs are conserved in plant ortholog DRL1/ELO4 from Arabidopsis thaliana and seem to be involved in binding of cofactors (e.g., nucleotides, calmodulin). Elongator interaction defects triggered by mutations in these motifs correlate with phenotypes typical for loss of U34 modification. Thus, tRNA modification by Elongator appears to require physical contact with Kti12, and our preliminary data suggest that metabolic signals may affect proper communication between them.

    Original languageEnglish
    Pages (from-to)1-13
    Number of pages13
    Issue number9
    Publication statusPublished - 5 Sept 2017


    • zymocin
    • ribotoxin
    • tRNase
    • Kti12
    • Elongator complex
    • tRNA anticodon modification


    Dive into the research topics of 'Use of a Yeast tRNase Killer Toxin to Diagnose Kti12 Motifs Required for tRNA Modification by Elongator'. Together they form a unique fingerprint.

    Cite this