Determining the molecular mechanism and functional importance of Eri1-dependent histone mRNA degradation
Final Report Abstract
During the past years we have established Eri1 as the major exonuclease that degrades the stem-loop of histone mRNAs. It was shown that Eri1 specifically targets those histone mRNAs that, at the end of S-phase, are marked for degradation through the untemplated addition of multiple uridines at their 3’ends. We have contributed to the mechanistic understanding of this paradigm of induced mRNA decay by showing that Eri1 gains specificity for oligouridylated transcripts through an interaction with the oligo(U)-binding heteroheptameric Lsm complex. In our model, Eri1 trims the 3’end of mature histone mRNAs, thereby destabilizing its own binding to the stem-loop and potentially alleviating recruitment by the Lsm complex. We have addressed and answered all the questions that were raised in our grant proposal. Oligouridylation as a post-transcriptional modification that induces mRNA and miRNA decay currently gains a lot of interest. Since we did not foresee that Eri1 is the first mammalian exonuclease that degrades oligouridylated RNAs, we had to establish several new tools in our lab that were not in the grant proposal, such as oligouridylation qPCR assay, 3’ linker ligation, RNA in vitro transcription and transfection. Using these tools, we created several results that do not directly correspond to experiments that were originally suggested, but can be inspected in our publication.
Publications
- Eri1 degrades the stem-loop of oligouridylated histone mRNAs to induce replication-dependent decay. Nat Struct Mol Bio. 2013, 20(1):73-81
Hoefig KP, Rath N, Heinz GA, Wolf C, Dameris J, Schepers A, Kremmer E, Ansel KM, Heissmeyer V
(See online at https://doi.org/10.1038/nsmb.2450) - T cell activation induces proteasomal degradation of Argonaute and rapid remodeling of the microRNA repertoire. J Exp Med. 2013, 210(2):417-32
Bronevetsky Y, Villarino AV, Eisley CJ, Barbeau R, Barczak AJ, Heinz GA, Kremmer E, Heissmeyer V, McManus MT, Erle DJ, Rao A, Ansel KM
(See online at https://doi.org/10.1084/jem.20111717) - Induced miR-99a expression represses Mtor cooperatively with miR-150 to promote regulatory T-cell differentiation. EMBO J. 2015, 34(9):1195-213
Warth SC, Hoefig KP, Hiekel A, Schallenberg S, Jovanovic K, Klein L, Kretschmer K, Ansel KM, Heissmeyer V
(See online at https://doi.org/10.15252/embj.201489589)
