@article{DenkSchmidtSchurretal.2021,
  author    = {Denk, S. and Schmidt, S. and Schurr, Y. and Schwarz, G. and Schote, F. and Diefenbacher, M. and Armendariz, C. and Dejure, F. and Eilers, M. and Wiegering, Armin},
  title     = {CIP2A regulates MYC translation (via its 5′UTR) in colorectal cancer},
  series = {International Journal of Colorectal Disease},
  volume    = {36},
  journal   = {International Journal of Colorectal Disease},
  number    = {5},
  doi       = {10.1007/s00384-020-03772-y},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-280092},
  pages     = {911-918},
  year      = {2021},
  abstract  = {Background Deregulated expression of MYC is a driver of colorectal carcinogenesis, suggesting that decreasing MYC expression may have significant therapeutic value. CIP2A is an oncogenic factor that regulates MYC expression. CIP2A is overexpressed in colorectal cancer (CRC), and its expression levels are an independent marker for long-term outcome of CRC. Previous studies suggested that CIP2A controls MYC protein expression on a post-transcriptional level. Methods To determine the mechanism by which CIP2A regulates MYC in CRC, we dissected MYC translation and stability dependent on CIP2A in CRC cell lines. Results Knockdown of CIP2A reduced MYC protein levels without influencing MYC stability in CRC cell lines. Interfering with proteasomal degradation of MYC by usage of FBXW7-deficient cells or treatment with the proteasome inhibitor MG132 did not rescue the effect of CIP2A depletion on MYC protein levels. Whereas CIP2A knockdown had marginal influence on global protein synthesis, we could demonstrate that, by using different reporter constructs and cells expressing MYC mRNA with or without flanking UTR, CIP2A regulates MYC translation. This interaction is mainly conducted by the MYC 5′UTR. Conclusions Thus, instead of targeting MYC protein stability as reported for other tissue types before, CIP2A specifically regulates MYC mRNA translation in CRC but has only slight effects on global mRNA translation. In conclusion, we propose as novel mechanism that CIP2A regulates MYC on a translational level rather than affecting MYC protein stability in CRC.},
  language  = {en}
}
@article{LibreSeisslerGuerreroetal.2021,
  author    = {Libre, Camille and Seissler, Tanja and Guerrero, Santiago and Batisse, Julien and Verriez, C{\´e}dric and Stupfler, Benjamin and Gilmer, Orian and Cabrera-Rodriguez, Romina and Weber, Melanie M. and Valenzuela-Fernandez, Agustin and Cimarelli, Andrea and Etienne, Lucie and Marquet, Roland and Paillart, Jean-Christophe},
  title     = {A conserved uORF regulates APOBEC3G translation and is targeted by HIV-1 Vif protein to repress the antiviral factor},
  series = {Biomedicines},
  volume    = {10},
  journal   = {Biomedicines},
  number    = {1},
  issn      = {2227-9059},
  doi       = {10.3390/biomedicines10010013},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-252147},
  year      = {2021},
  abstract  = {The HIV-1 Vif protein is essential for viral fitness and pathogenicity. Vif decreases expression of cellular restriction factors APOBEC3G (A3G), A3F, A3D and A3H, which inhibit HIV-1 replication by inducing hypermutation during reverse transcription. Vif counteracts A3G at several levels (transcription, translation, and protein degradation) that altogether reduce the levels of A3G in cells and prevent its incorporation into viral particles. How Vif affects A3G translation remains unclear. Here, we uncovered the importance of a short conserved uORF (upstream ORF) located within two critical stem-loop structures of the 5′ untranslated region (5′-UTR) of A3G mRNA for this process. A3G translation occurs through a combination of leaky scanning and translation re-initiation and the presence of an intact uORF decreases the extent of global A3G translation under normal conditions. Interestingly, the uORF is also absolutely required for Vif-mediated translation inhibition and redirection of A3G mRNA into stress granules. Overall, we discovered that A3G translation is regulated by a small uORF conserved in the human population and that Vif uses this specific feature to repress its translation.},
  language  = {en}
}
@article{WenckerMarincolaSchoenfelderetal.2021,
  author    = {Wencker, Freya D. R and Marincola, Gabriella and Schoenfelder, Sonja M. K. and Maaß, Sandra and Becher, D{\"o}rte and Ziebuhr, Wilma},
  title     = {Another layer of complexity in Staphylococcus aureus methionine biosynthesis control: unusual RNase III-driven T-box riboswitch cleavage determines met operon mRNA stability and decay},
  series = {Nucleic Acids Research},
  volume    = {49},
  journal   = {Nucleic Acids Research},
  number    = {4},
  doi       = {10.1093/nar/gkaa1277},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259029},
  pages     = {2192-2212},
  year      = {2021},
  abstract  = {In Staphylococcus aureus, de novo methionine biosynthesis is regulated by a unique hierarchical pathway involving stringent-response controlled CodY repression in combination with a T-box riboswitch and RNA decay. The T-box riboswitch residing in the 5′ untranslated region (met leader RNA) of the S. aureus metICFE-mdh operon controls downstream gene transcription upon interaction with uncharged methionyl-tRNA. met leader and metICFE-mdh (m)RNAs undergo RNase-mediated degradation in a process whose molecular details are poorly understood. Here we determined the secondary structure of the met leader RNA and found the element to harbor, beyond other conserved T-box riboswitch structural features, a terminator helix which is target for RNase III endoribonucleolytic cleavage. As the terminator is a thermodynamically highly stable structure, it also forms posttranscriptionally in met leader/ metICFE-mdh read-through transcripts. Cleavage by RNase III releases the met leader from metICFE-mdh mRNA and initiates RNase J-mediated degradation of the mRNA from the 5′-end. Of note, metICFE-mdh mRNA stability varies over the length of the transcript with a longer lifespan towards the 3′-end. The obtained data suggest that coordinated RNA decay represents another checkpoint in a complex regulatory network that adjusts costly methionine biosynthesis to current metabolic requirements.},
  language  = {en}
}