Next Article in Journal
Karyotype Characterization of Nine Periwinkle Species (Gastropoda, Littorinidae)
Next Article in Special Issue
Nucleotide Modifications Decrease Innate Immune Response Induced by Synthetic Analogs of snRNAs and snoRNAs
Previous Article in Journal
Evolution of Plant B Chromosome Enriched Sequences
Previous Article in Special Issue
Above the Epitranscriptome: RNA Modifications and Stem Cell Identity
Article Menu
Issue 11 (November) cover image

Export Article

Open AccessCommunication

Unfolded Protein Response Suppression in Yeast by Loss of tRNA Modifications

Institut für Biologie, Fachgebiet Mikrobiologie, Universität Kassel, Heinrich-Plett-Str. 40, D-34132 Kassel, Germany
Author to whom correspondence should be addressed.
Genes 2018, 9(11), 516;
Received: 24 September 2018 / Revised: 18 October 2018 / Accepted: 18 October 2018 / Published: 23 October 2018
(This article belongs to the Special Issue RNA Modifications)
PDF [1396 KB, uploaded 23 October 2018]


Modifications in the anticodon loop of transfer RNAs (tRNAs) have been shown to ensure optimal codon translation rates and prevent protein homeostasis defects that arise in response to translational pausing. Consequently, several yeast mutants lacking important anticodon loop modifications were shown to accumulate protein aggregates. Here we analyze whether this includes the activation of the unfolded protein response (UPR), which is commonly triggered by protein aggregation within the endoplasmic reticulum (ER). We demonstrate that two different aggregation prone tRNA modification mutants (elp6 ncs2; elp3 deg1) lacking combinations of 5-methoxycarbonylmethyl-2-thiouridine (mcm5s2U: elp3; elp6; ncs2) and pseudouridine (Ψ: deg1) reduce, rather than increase, splicing of HAC1 mRNA, an event normally occurring as a precondition of UPR induction. In addition, tunicamycin (TM) induced HAC1 splicing is strongly impaired in the elp3 deg1 mutant. Strikingly, this mutant displays UPR independent resistance against TM, a phenotype we found to be rescued by overexpression of tRNAGln(UUG), the tRNA species usually carrying the mcm5s2U34 and Ψ38 modifications. Our data indicate that proper tRNA anticodon loop modifications promote rather than impair UPR activation and reveal that protein synthesis and homeostasis defects in their absence do not routinely result in UPR induction but may relieve endogenous ER stress. View Full-Text
Keywords: tRNA anticodon modifications; unfolded protein response; tunicamycin; yeast; elongator complex; Deg1 tRNA anticodon modifications; unfolded protein response; tunicamycin; yeast; elongator complex; Deg1

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Supplementary material


Share & Cite This Article

MDPI and ACS Style

Bruch, A.; Klassen, R.; Schaffrath, R. Unfolded Protein Response Suppression in Yeast by Loss of tRNA Modifications. Genes 2018, 9, 516.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Genes EISSN 2073-4425 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top