@article{RunggerCrippaTrendelenburgetal.1978,
  author    = {Rungger, M. and Crippa, M. and Trendelenburg, M. F. and Scheer, Ulrich and Franke, Werner W.},
  title     = {Visualization of rDNA spacer transcription in Xenopus oocytes treated with fluorouridine},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-33082},
  year      = {1978},
  abstract  = {Under the intluence of 5-tluoro-uridine, the ultrastructure of the rDNA transcription units in Xenopus oocytes is altered. Whereas part of the matrix units maintains anormal aspect or shows various degrees of inhibition, in a strong proportion of the transcription units the alternating pattern of matrix units and fibril-free spacer regions is no longer recognized. Transcriptional complexes are found along the entire DNP axis, including the regions of the spacers. These observations support biochemical data on transcription in rDNA spacer region.},
  language  = {en}
}
@inproceedings{TrendelenburgFrankeSpringetal.1975,
  author    = {Trendelenburg, M. F. and Franke, Werner W. and Spring, H. and Scheer, Ulrich},
  title     = {Ultrastructure of transcription in the nucleoli of the green algae Acetabularia major and A. mediterranea},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-33779},
  year      = {1975},
  abstract  = {No abstract available},
  language  = {en}
}
@inproceedings{ScheerFranke1976,
  author    = {Scheer, Ulrich and Franke, Werner W.},
  title     = {Transcriptional complexes of nucleolar genes},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-41072},
  year      = {1976},
  abstract  = {No abstract available},
  language  = {en}
}
@incollection{ScheerKleinschmidtFranke1982,
  author    = {Scheer, Ulrich and Kleinschmidt, J{\"u}rgen A. and Franke, Werner W.},
  title     = {Transcriptional and skeletal elements in nucleoli of amphibian oocytes},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-40625},
  publisher      = {Universit{\"a}t W{\"u}rzburg},
  year      = {1982},
  abstract  = {No abstract available},
  language  = {en}
}
@article{ScheerTrendelenburgFranke1973,
  author    = {Scheer, Ulrich and Trendelenburg, Michael F. and Franke, Werner W.},
  title     = {Transcription of ribosomal RNA cistrons: Correlation of morphological and biochemical data},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-32195},
  year      = {1973},
  abstract  = {Electron microscopic spread preparations of oocyte nucleoli (lampbrush stage) of various amphibians are quantitatively evaluated and the length distributions of repeat-, matrix-, and spacer-units along the rRNA cistron containing axes are given. The correlation of the matrix unit data with the gel electrophoretic pattern of labelled nuclear RNA from the same oocytes is examined. The mean value of the matrix unit corresponds fairly well to a 2.6 million D peak of pre-rRNA but the distribution of both matrix units and labelled pre-rRNAs shows an asymmetrical heterogeneity indicating the existence of some larger primary transcription products of rDNA. Novel structural aspects are described in the spacer regions which suggest that transcription does also take place in DNP regions between the matrix units. A special "prelude piece" coding for approx. 0.5 million D of RNA is frequently visualized in the spacer segments at the beginning of a matrix unit. Possible artifacts resulting from the preparation, the relative congruence between the data obtained using both methods, and the functional meaning of the findings are discussed against the background of current concepts of structural organization and transcription products of nucleolar DNA.},
  language  = {en}
}
@article{FrankeScheer1970,
  author    = {Franke, Werner W. and Scheer, Ulrich},
  title     = {The ultrastructure of the nuclear envelope of amphibian oocytes: a reinvestigation. II. The immature oocyte and dynamic aspects},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-32102},
  year      = {1970},
  abstract  = {No abstract available},
  language  = {en}
}
@article{FrankeScheer1970,
  author    = {Franke, Werner W. and Scheer, Ulrich},
  title     = {The ultrastructure of the nuclear envelope of amphibian oocytes: a reinvestigation. I. The mature oocyte},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-32098},
  year      = {1970},
  abstract  = {1 n order to review the contradictory statements on the ultrast ructure of the nuclear envelope, a study was undertaken combining section and negat ive stai ning electron microscopy on manually isolated oocyte nuclei and nuclear envelopes from six amphibian species including Anura as well as Urodela. The a ppeara nce of the negatively stained iso lated nuclear envelopes is described in deta il and the dependence on the preparation co nditions used is emphas ized . Pore complex structures such as pore perimeter, central granule, an nul ar components, interna l fibrils, and annu lus-attached fibrils could be identified by both techniques, negat ive staining and sect ions. Comparative studies show that no marked diffe rences ex ist in the structural data of the nuclear envelope among the investigated amphibians and the significance of the structural components is discussed. A model of the nuclea r pore complex based on the findings of the present investigation is prese nted.},
  language  = {en}
}
@book{KartenbeckZentgrafScheeretal.1971,
  author    = {Kartenbeck, J. and Zentgraf, H. and Scheer, Ulrich and Franke, Werner W.},
  title     = {The nuclear envelope in freeze-etching},
  isbn      = {3-540-05538-X},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-40534},
  publisher      = {Universit{\"a}t W{\"u}rzburg},
  year      = {1971},
  abstract  = {No abstract available},
  subject      = {Anatomie},
  language  = {en}
}
@article{FrankeScheerKrohneetal.1981,
  author    = {Franke, Werner W. and Scheer, Ulrich and Krohne, Georg and Jarasch, Ernst-Dieter},
  title     = {The nuclear envelope and the architecture of the nuclear periphery},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-33108},
  year      = {1981},
  abstract  = {No abstract available},
  language  = {en}
}
@article{KrohneFrankeScheer1978,
  author    = {Krohne, Georg and Franke, Werner W. and Scheer, Ulrich},
  title     = {The major polypeptides of the nuclear pore complex},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-33078},
  year      = {1978},
  abstract  = {Nuclear envelopes of maturing oocytes of various amphibia contain an unusually high number of pore complexes in very close packing. Consequently, nuclear envelopes , which can be manually isolated in great purity, provide a remarkable enrichment of nuclear pore complex material, relative to membranous and other interporous structures. When the polypeptides of nuclear envelopes isolated from oocytes of Xenopl/s la evis and Triturus alpestris are examined by gel electrophoresis, visualized either by staining with Coomassie blue or by radiotluorography after in vitro reaction with [3H]dansyl chloride , a characteristic pattern is obtained (10 major and 15 minor bands). This polypeptide pattern is radically different from that of the nuclear contents isolated from the same cell. Extraction of the nuclear envelope with high salt concentrations and moderateIy ac tive detergents such as Triton X- 100 results in the removal of membrane material but leaves most of the non-membranous structure of the pore complexes. The dry weight of the pore complex (about 0.2 femtograms) remains essentially unchanged during such extractions as measured by quantitative electron microscopy . The extracted preparations which are highly enriched in nuclear pore complex material contain only two major polypeptide components with apparent molecular weights of 150000 and 73000. Components of such an electrophoretic mobility are not present as major bands , if at all , in nuclear contents extracted in the same way. lt is concluded that these two polypeptides are the major constituent protein(s) of the oocyte nuclear pore complex and are specific for this structure. When nuclear envelopes are isolated from rat liver and extracted with high salt buffers and Triton X- 100 similar bands are predominant, but two additional major components of molecular weights of 78000 and 66000 are also recognized. When the rat liver nuclear membranes are further subfractionated material enriched in the 66000 molecular weight component can be separated from the membrane material, indicating that this is relatively loosely associated material , probably a part of the nuclear matrix . The results suggest that the nuclear pore complex is not only a characteristic ubiquitous structure but also contains similar, if not identical , skeletal proteins that are remarkably re sistant to drastic changes of ionic strength as weil as to treatments with detergents and thiol reagents.},
  language  = {en}
}