@article{BodemSchromMoschalletal.2013,
  author    = {Bodem, Jochen and Schrom, Eva-Maria and Moschall, Rebecca and Hartl, Maximilian J. and Weitner, Helena and Fecher, David and Langemeier, J{\"o}rg and W{\"o}hrl, Brigitta M.},
  title     = {U1snRNP-mediated suppression of polyadenylation in conjunction with the RNA structure controls poly (A) site selection in foamy viruses},
  series = {Retrovirology},
  journal   = {Retrovirology},
  doi       = {10.1186/1742-4690-10-55},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96085},
  year      = {2013},
  abstract  = {Background During reverse transcription, retroviruses duplicate the long terminal repeats (LTRs). These identical LTRs carry both promoter regions and functional polyadenylation sites. To express full-length transcripts, retroviruses have to suppress polyadenylation in the 5′LTR and activate polyadenylation in the 3′LTR. Foamy viruses have a unique LTR structure with respect to the location of the major splice donor (MSD), which is located upstream of the polyadenylation signal. Results Here, we describe the mechanisms of foamy viruses regulating polyadenylation. We show that binding of the U1 small nuclear ribonucleoprotein (U1snRNP) to the MSD suppresses polyadenylation at the 5′LTR. In contrast, polyadenylation at the 3′LTR is achieved by adoption of a different RNA structure at the MSD region, which blocks U1snRNP binding and furthers RNA cleavage and subsequent polyadenylation. Conclusion Recently, it was shown that U1snRNP is able to suppress the usage of intronic cryptic polyadenylation sites in the cellular genome. Foamy viruses take advantage of this surveillance mechanism to suppress premature polyadenylation at the 5'end of their RNA. At the 3'end, Foamy viruses use a secondary structure to presumably block access of U1snRNP and thereby activate polyadenylation at the end of the genome. Our data reveal a contribution of U1snRNP to cellular polyadenylation site selection and to the regulation of gene expression.},
  subject      = {Polyadenylierung},
  language  = {en}
}
@article{FecherHofmannBucketal.2016,
  author    = {Fecher, David and Hofmann, Elisabeth and Buck, Andreas and Bundschuh, Ralph and Nietzer, Sarah and Dandekar, Gudrun and Walles, Thorsten and Walles, Heike and L{\"u}ckerath, Katharina and Steinke, Maria},
  title     = {Human Organotypic Lung Tumor Models: Suitable For Preclinical \(^{18}\)F-FDG PET-Imaging},
  series = {PLoS ONE},
  volume    = {11},
  journal   = {PLoS ONE},
  number    = {8},
  doi       = {10.1371/journal.pone.0160282},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-179678},
  year      = {2016},
  abstract  = {Development of predictable in vitro tumor models is a challenging task due to the enormous complexity of tumors in vivo. The closer the resemblance of these models to human tumor characteristics, the more suitable they are for drug-development and -testing. In the present study, we generated a complex 3D lung tumor test system based on acellular rat lungs. A decellularization protocol was established preserving the architecture, important ECM components and the basement membrane of the lung. Human lung tumor cells cultured on the scaffold formed cluster and exhibited an up-regulation of the carcinoma-associated marker mucin1 as well as a reduced proliferation rate compared to respective 2D culture. Additionally, employing functional imaging with 2-deoxy-2-[\(^{18}\)F]fluoro-D-glucose positron emission tomography (FDG-PET) these tumor cell cluster could be detected and tracked over time. This approach allowed monitoring of a targeted tyrosine kinase inhibitor treatment in the in vitro lung tumor model non-destructively. Surprisingly, FDG-PET assessment of single tumor cell cluster on the same scaffold exhibited differences in their response to therapy, indicating heterogeneity in the lung tumor model. In conclusion, our complex lung tumor test system features important characteristics of tumors and its microenvironment and allows monitoring of tumor growth and -metabolism in combination with functional imaging. In longitudinal studies, new therapeutic approaches and their long-term effects can be evaluated to adapt treatment regimes in future.},
  language  = {en}
}