@article{SpringTrendelenbrugScheeretal.1974,
  author    = {Spring, Herbert and Trendelenbrug, Michael F. and Scheer, Ulrich and Franke, Werner W. and Herth, Werner},
  title     = {Structural and biochemical studies of the primary nucleus of two green algal species, Acetabularia mediterranea and Acetabularia major},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-40600},
  year      = {1974},
  abstract  = {Primary (giant) nuclei of the green algae Acetabularia mediterranea and A. major were studied by light and electron microscopy using in situ fixed material as well as manually isolated nuclear components. In addition, cytochemical reactions of nuclear structures and biochemical determinations of nuclear and cytoplasmic RNA and of genome DNA content were performed. The data obtained and the structures observed are interpreted as demonstralions of transcriptional activities of different gene classes. The most prominent class is the nucleolar cistrons of precursors of ribosomal RNA which occur highly repeated in clusters in the form of regularly alternating intercepts on deoxyribonucleoprotein axes of transcribed rDNA, the fibril-covered matrix units, and the fibril-free "spacer" segments. A description and a classification of the various structural complexes which seem to represent transcriptional activities is given. Quantitative evaluations of these arrangements are presented. The morphology and the dimensions of such structures are compared with the RNA molecular weight determinations and with the corresponding data reported from various animal cell systems. It is suggested that the formation of the giant nucleus is correlated with, and probably due to, an enormous amplification of transcriptionally active rDNA and packing of the extrachromosomal copies into the large nucleolar aggregate bodies.},
  subject      = {Cytologie},
  language  = {en}
}
@article{FrankeScheerHerth1974,
  author    = {Franke, Werner W. and Scheer, Ulrich and Herth, Werner},
  title     = {Cytology, general and molecular cytology},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-39499},
  year      = {1974},
  abstract  = {The present article had originally been conceived as a review on endomembranes, the plasma membrane, and the major product of membrane-bound activities, the cell wall material. However, limitations of space and the cascading number of pertinent literature articles made it necessary to confine this to one group of membranes and one type of cell wall components. Therefore, we shall begin our survey on the biochemical and cytological aspects of membranes by a review of the class of the pore complex bearing endomembranes, i.e. the nuclear envelope and the annulate lamellae (AL). Next year the membranes of the endoplasmic reticulum and the dictyosomes will be dealt with in conjunction with a discussion of the various intracellular vesicles, the tonoplast and the plasmalemma.},
  subject      = {Botanik},
  language  = {en}
}
@incollection{ScheerFranke1974,
  author    = {Scheer, Ulrich and Franke, Werner W.},
  title     = {Structures and functions of the nuclear envelope},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-39777},
  publisher      = {Universit{\"a}t W{\"u}rzburg},
  year      = {1974},
  abstract  = {No abstract available},
  subject      = {Zellkern},
  language  = {en}
}
@article{FrankeBergerFalketal.1974,
  author    = {Franke, Werner W. and Berger, S. and Falk, Heinz and Spring, H. and Scheer, Ulrich and Trendelenburg, Michael F. and Schweiger, H. G. and Herth, W.},
  title     = {Morphology of the nucleo-cytoplasmic interactions during the development of Acetabularia cells. I. The vegetative phase},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-32363},
  year      = {1974},
  abstract  = {The ultrastructure of th e growin g and ma turing primary nucleus of Acetabularia medite rranea and Acetabularia major has been studied with the use of various fi xation procedures. Particular interest has been focused on the deta ils of the nuclear periphery and the perinuclear region. It is demonstrated that early in nuclear grow th a characteristic perinucl ear structura l complex is formed which is, among the eukaryotic cells, unique to Acetabularia and re lated genera. This perinuclear system consists essentially of a) the nuclear envelope with a very hi gh pore frequency and various pore complex assoc iat ion s w ith granular and/or threadlike structures some of which are continuous with the nucleolus; b) an approx imate ly 100 nm thick intermediate zone densely filled with a filam entOus material and occasional sma ll membraneous structures from which the typical cytOplasmic and nuclear organe lles and particles are excl ud ed ; c) an adjacent Iacunar labyrinthum which is interrupted by many plasmatic junction channels between the intermed iate zone and the free cytOplasm; d) numerous dense perinuclear bodies in the juxtanuclear cytOplasm which a re especia lly frequent at the junction channels and reveal a composition of aggregated fibrillar and granul ar structures; e) very dense exclusively fibrill ar agg regates which occur either in assoc iation with t he perinuclear region of the lacunar labyrinthum or, somewhat further out, in the cytOplasmic strands between the bra nches of the lacun ar labyrinthum in the form of slender, characteristic rods or "sausages".},
  language  = {en}
}
@inproceedings{FrankeScheer1974,
  author    = {Franke, Werner W. and Scheer, Ulrich},
  title     = {Pathways of nucleocytoplasmic translocation of ribonucleoproteins},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-33832},
  year      = {1974},
  abstract  = {No abstract available},
  language  = {en}
}
@inproceedings{TrendelenburgSpringScheeretal.1974,
  author    = {Trendelenburg, Michael F. and Spring, Herbert and Scheer, Ulrich and Franke, Werner W.},
  title     = {Morphology of nucleolar cistrons in a plant cell, Acetabularia mediterranea},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-32213},
  year      = {1974},
  abstract  = {The structural organization of transcriptionally active DNA that contains cistrons for precursor molecules of ribosomal RNA is described in positively stained spread preparations from nuclei and nucleoli isolated from the green alga, Acetabularia mediterranea Lmx. These nuclei contain large aggregates of nucleolar subunits in which fibril-covered regions, the putative active cistrons for precursors of ribosomal RNA, alternate with fibril-free intercepts, the "spacers". The length distribution of the different intercepts of this DNA is given, and the pattern is compared with those shown in animal cell systems. The data are discussed in relation to problems of transcription and of amplification of ribosomal RNA genes.},
  language  = {en}
}