@article{SieversWenzHausmannetal.2018, author = {Sievers, Aaron and Wenz, Frederik and Hausmann, Michael and Hildenbrand, Georg}, title = {Conservation of k-mer Composition and Correlation Contribution between Introns and Intergenic Regions of Animalia Genomes}, series = {Genes}, volume = {9}, journal = {Genes}, number = {10}, publisher = {MDPI AG}, issn = {2073-4425}, doi = {https://doi.org/10.3390/genes9100482}, year = {2018}, abstract = {In this study, we pairwise-compared multiple genome regions, including genes, exons, coding DNA sequences (CDS), introns, and intergenic regions of 39 Animalia genomes, including Deuterostomia (27 species) and Protostomia (12 species), by applying established k-mer-based (alignment-free) comparison methods. We found strong correlations between the sequence structure of introns and intergenic regions, individual organisms, and within wider phylogenetical ranges, indicating the conservation of certain structures over the full range of analyzed organisms. We analyzed these sequence structures by quantifying the contribution of different sets of DNA words to the average correlation value by decomposing the correlation coefficients with respect to these word sets. We found that the conserved structures within introns, intergenic regions, and between the two were mainly a result of conserved tandem repeats with repeat units ≤ 2 bp (e.g., (AT)n), while other conserved sequence structures, such as those found between exons and CDS, were dominated by tandem repeats with repeat unit sizes of 3 bp in length and more complex DNA word patterns. We conclude that the conservation between intron and intergenic regions indicates a shared function of these sequence structures. Also, the similar differences in conserved structures with known origin, especially to the conservation between exons and CDS resulting from DNA codons, indicate that k-mer composition-based functional properties of introns and intergenic regions may differ from those of exons and CDS.}, subject = {Genom}, language = {en} } @article{BobkovaDepesLeeetal.2018, author = {Bobkova, Elizaveta and Depes, Daniel and Lee, Jin-Ho and Jezkova, Lucie and Falkova, Iva and Pagacova, Eva and Kopecna, Olga and Zadneprianetc, Mariia and Bacikova, Alena and Kulikova, Elena and Smirnova, Elena and Bulanova, Tatiana and Boreyko, Alla and Krasavin, Evgeny and Wenz, Frederik and Bestvater, Felix and Hildenbrand, Georg and Hausmann, Michael and Falk, Martin}, title = {Recruitment of 53BP1 Proteins for DNA Repair and Persistence of Repair Clusters Differ for Cell Types as Detected by Single Molecule Localization Microscopy}, series = {International Journal of Molecular Sciences}, volume = {19}, journal = {International Journal of Molecular Sciences}, number = {12}, publisher = {MDPI AG}, issn = {1422-0067}, doi = {https://doi.org/10.3390/ijms19123713}, year = {2018}, abstract = {DNA double stranded breaks (DSBs) are the most serious type of lesions introduced into chromatin by ionizing radiation. During DSB repair, cells recruit different proteins to the damaged sites in a manner dependent on local chromatin structure, DSB location in the nucleus, and the repair pathway entered. 53BP1 is one of the important players participating in repair pathway decision of the cell. Although many molecular biology details have been investigated, the architecture of 53BP1 repair foci and its development during the post-irradiation time, especially the period of protein recruitment, remains to be elucidated. Super-resolution light microscopy is a powerful new tool to approach such studies in 3D-conserved cell nuclei. Recently, we demonstrated the applicability of single molecule localization microscopy (SMLM) as one of these highly resolving methods for analyses of dynamic repair protein distribution and repair focus internal nano-architecture in intact cell nuclei. In the present study, we focused our investigation on 53BP1 foci in differently radio-resistant cell types, moderately radio-resistant neonatal human dermal fibroblasts (NHDF) and highly radio-resistant U87 glioblastoma cells, exposed to high-LET 15N-ion radiation. At given time points up to 24 h post irradiation with doses of 1.3 Gy and 4.0 Gy, the coordinates and spatial distribution of fluorescently tagged 53BP1 molecules was quantitatively evaluated at the resolution of 10-20 nm. Clusters of these tags were determined as sub-units of repair foci according to SMLM parameters. The formation and relaxation of such clusters was studied. The higher dose generated sufficient numbers of DNA breaks to compare the post-irradiation dynamics of 53BP1 during DSB processing for the cell types studied. A perpendicular (90°) irradiation scheme was used with the 4.0 Gy dose to achieve better separation of a relatively high number of particle tracks typically crossing each nucleus. For analyses along ion-tracks, the dose was reduced to 1.3 Gy and applied in combination with a sharp angle irradiation (10° relative to the cell plane). The results reveal a higher ratio of 53BP1 proteins recruited into SMLM defined clusters in fibroblasts as compared to U87 cells. Moreover, the speed of foci and thus cluster formation and relaxation also differed for the cell types. In both NHDF and U87 cells, a certain number of the detected and functionally relevant clusters remained persistent even 24 h post irradiation; however, the number of these clusters again varied for the cell types. Altogether, our findings indicate that repair cluster formation as determined by SMLM and the relaxation (i.e., the remaining 53BP1 tags no longer fulfill the cluster definition) is cell type dependent and may be functionally explained and correlated to cell specific radio-sensitivity. The present study demonstrates that SMLM is a highly appropriate method for investigations of spatiotemporal protein organization in cell nuclei and how it influences the cell decision for a particular repair pathway at a given DSB site.}, subject = {Genom}, language = {en} } @article{HildenbrandMetzlerPilarczyketal.2018, author = {Hildenbrand, Georg and Metzler, Philipp and Pilarczyk, G{\"o}tz and Bobu, Vladimir and Kriz, Wilhelm and Hosser, Hiltraud and Fleckenstein, Jens and Krufczik, Matthias and Bestvater, Felix and Wenz, Frederik and Hausmann, Michael}, title = {Dose enhancement effects of gold nanoparticles specifically targeting RNA in breast cancer cells}, series = {PLOS ONE}, volume = {13}, journal = {PLOS ONE}, number = {1}, editor = {Baptista, Pedro V.}, publisher = {Public Library of Science (PLoS)}, issn = {1932-6203}, doi = {https://doi.org/10.1371/journal.pone.0190183}, year = {2018}, subject = {Krebs, Medizin}, language = {en} }