@article{TessmerMelikishviliFried2012,
  author    = {Tessmer, Ingrid and Melikishvili, Manana and Fried, Michael G.},
  title     = {Cooperative cluster formation, DNA bending and base-flipping by O\(^6\)-alkylguanine-DNA alkyltransferase},
  series = {Nucleic Acids Research},
  volume    = {40},
  journal   = {Nucleic Acids Research},
  number    = {17},
  doi       = {10.1093/nar/gks574},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133949},
  pages     = {8296-8308},
  year      = {2012},
  abstract  = {O\(^6\)-Alkylguanine-DNA alkyltransferase (AGT) repairs mutagenic O\(^6\)-alkylguanine and O\(^4\)-alkylthymine adducts in DNA, protecting the genome and also contributing to the resistance of tumors to chemotherapeutic alkylating agents. AGT binds DNA cooperatively, and cooperative interactions are likely to be important in lesion search and repair. We examined morphologies of complexes on long, unmodified DNAs, using analytical ultracentrifugation and atomic force microscopy. AGT formed clusters of 11 proteins. Longer clusters, predicted by the McGhee-von Hippel model, were not seen even at high [protein]. Interestingly, torsional stress due to DNA unwinding has the potential to limit cluster size to the observed range. DNA at cluster sites showed bend angles (similar to 0, similar to 30 and similar to 60 degrees) that are consistent with models in which each protein induces a bend of similar to 30 degrees. Distributions of complexes along the DNA are incompatible with sequence specificity but suggest modest preference for DNA ends. These properties tell us about environments in which AGT may function. Small cooperative clusters and the ability to accommodate a range of DNA bends allow function where DNA topology is constrained, such as near DNA-replication complexes. The low sequence specificity allows efficient and unbiased lesion search across the entire genome.},
  language  = {en}
}
@article{PiteauPapatheodorouSchwanetal.2014,
  author    = {Piteau, Marianne and Papatheodorou, Panagiotis and Schwan, Carsten and Schlosser, Andreas and Aktories, Klaus and Schmidt, Gudula},
  title     = {Lu/BCAM Adhesion Glycoprotein Is a Receptor for Escherichia coli Cytotoxic Necrotizing Factor 1 (CNF1)},
  series = {PLoS Pathogens},
  volume    = {10},
  journal   = {PLoS Pathogens},
  number    = {1},
  issn      = {1553-7374},
  doi       = {10.1371/journal.ppat.1003884},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-117987},
  pages     = {e1003884},
  year      = {2014},
  abstract  = {The Cytotoxic Necrotizing Factor 1 (CNF1) is a protein toxin which is a major virulence factor of pathogenic Escherichia coli strains. Here, we identified the Lutheran (Lu) adhesion glycoprotein/basal cell adhesion molecule (BCAM) as cellular receptor for CNF1 by co-precipitation of cell surface molecules with tagged toxin. The CNF1-Lu/BCAM interaction was verified by direct protein-protein interaction analysis and competition studies. These studies revealed amino acids 720 to 1014 of CNF1 as the binding site for Lu/BCAM. We suggest two cell interaction sites in CNF1: first the N-terminus, which binds to p37LRP as postulated before. Binding of CNF1 to p37LRP seems to be crucial for the toxin's action. However, it is not sufficient for the binding of CNF1 to the cell surface. A region directly adjacent to the catalytic domain is a high affinity interaction site for Lu/BCAM. We found Lu/BCAM to be essential for the binding of CNF1 to cells. Cells deficient in Lu/BCAM but expressing p37LRP could not bind labeled CNF1. Therefore, we conclude that LRP and Lu/BCAM are both required for toxin action but with different functions. Author Summary We study a crucial virulence factor produced by pathogenic Escherichia coli strains, the Cytotoxic Necrotizing Factor 1 (CNF1). More than 80\% of urinary tract infections (UTIs), which are counted among the most common bacterial infections of humans, are caused by Uropathogenic Escherichia coli (UPEC) strains. We and others elucidated the molecular mechanism of the E. coli toxin CNF1. It constitutively activates Rho GTPases by a direct covalent modification. The toxin enters mammalian cells by receptor-mediated endocytosis. Here, we identified the protein receptor for CNF1 by co-precipitation of cell surface molecules with the tagged toxin and subsequent Maldi-TOF analysis. We identified the Lutheran (Lu) adhesion glycoprotein/basal cell adhesion molecule (BCAM) as receptor for CNF1 and located its interaction site to the C-terminal part of the toxin. We performed direct protein-protein interaction analysis and competition studies. Moreover, cells deficient in Lu/BCAM could not bind labeled CNF1. The identification of a toxin's cellular receptor and receptor binding region is an important task for understanding the pathogenic function of the toxin and, moreover, to make the toxin accessible for its use as a cellbiological and pharmacological tool, for example for the generation of immunotoxins.},
  language  = {en}
}
@article{FaganDollarLuetal.2014,
  author    = {Fagan, Jeremy K. and Dollar, Gretchen and Lu, Qiuheng and Barnett, Austen and Jorge, Joaquin Pechuan and Schlosser, Andreas and Pfleger, Cathie and Adler, Paul and Jenny, Andreas},
  title     = {Combover/CG10732, a Novel PCP Effector for Drosophila Wing Hair Formation},
  series = {PLOS ONE},
  volume    = {9},
  journal   = {PLOS ONE},
  number    = {9},
  issn      = {1932-6203},
  doi       = {10.1371/journal.pone.0107311},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-115394},
  pages     = {e107311},
  year      = {2014},
  abstract  = {The polarization of cells is essential for the proper functioning of most organs. Planar Cell Polarity (PCP), the polarization within the plane of an epithelium, is perpendicular to apical-basal polarity and established by the non-canonical Wnt/Fz-PCP signaling pathway. Within each tissue, downstream PCP effectors link the signal to tissue specific readouts such as stereocilia orientation in the inner ear and hair follicle orientation in vertebrates or the polarization of ommatidia and wing hairs in Drosophila melanogaster. Specific PCP effectors in the wing such as Multiple wing hairs (Mwh) and Rho Kinase (Rok) are required to position the hair at the correct position and to prevent ectopic actin hairs. In a genome-wide screen in vitro, we identified Combover (Cmb)/CG10732 as a novel Rho kinase substrate. Overexpression of Cmb causes the formation of a multiple hair cell phenotype (MHC), similar to loss of rok and mwh. This MHC phenotype is dominantly enhanced by removal of rok or of other members of the PCP effector gene family. Furthermore, we show that Cmb physically interacts with Mwh, and cmb null mutants suppress the MHC phenotype of mwh alleles. Our data indicate that Cmb is a novel PCP effector that promotes to wing hair formation, a function that is antagonized by Mwh.},
  language  = {en}
}