ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Biochemical and Structural Analyses of Microtubules in the Pellicular Membrane of Leishmania tropica (1982)
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 29 (1982), S. 0 
    Details
    ISSN: 1550-7408
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: The structure of the major protein of the pellicular membrane of Leishmania tropica was investigated. This protein is composed of two polypeptides, of ca. 50,000 d molecular weight, that were found to cross-react immunologically with the α and β subunits of pig brain tubulin. The polypeptides and pig brain tubulin subunits were partially digested with S. aureus V8 protease, and the peptides obtained analysed by SDS-polyacrylamide gel electrophoresis. A comparison of the patterns showed that the β subunits of Leishmania and pig tubulin have very similar primary structures, while the α subunits have evolved divergently. These experiments demonstrate that the major polypeptides found in the pellicular membrane of L. tropica are α and β subunits of tubulin. Immuno-electron microscopy indicates that the tubulin is located in the microtubules associated with the pellicular membrane of Leishmania. Arrays of microtubules were prepared by nonionic detergent treatment of the cells and observed by electron microscopy after negative staining. Optical diffraction reveals a 5 nm spacing between protofilaments in the microtubule and a 4 nm axial periodicity corresponding to the tubulin subunits. The pitch of the shallow left-hand three-start helix is 12°. A distance of 47 nm separates each microtubule from the next. These data show that the dimensions and supramolecular organization of the tubulin subunits in the microtubules are identical in the pellicular membrane of L. tropica and in mammalian brain.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1550-7408.1982.tb01335.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Comparative studies on the structural organization of membrane-depleted nuclei and metaphase chromosomes (1983)
    Springer
    Chromosoma 88 (1983), S. 241-248 
    Details
    ISSN: 1432-0886
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Interphase membrane-depleted nuclei and metaphase chromosomes were prepared in parallel with a nonionic detergent lysis procedure at low ionic strength. By flow microfluorometry we showed for the first time that cell lysates contain all stages of the cell cycle in the same proportions as the starting cell population. Morphologically intact membrane-depleted nuclei and metaphase chromosomes were isolated as non-aggregated structures on sucrose gradients. When analysed in the electron microscope, membrane-depleted nuclei that had been treated with 2M NaCl appeared as residual structures containing the pore complex-lamina layer attached to a halo of DNA filaments. In contrast, no distinct high salt-resistant structure was found with metaphase chromosomes. They formed a highly fragile network which disintegrated easily into small complexes connected with DNA filaments. High salt-resistant DNA-protein complexes were purified by Metrizamide density gradient centrifugation. The main difference in the protein composition of interphase and metaphase residual complexes was the presence in interphase of a protein triplet in the 60–75 kilodalton molecular weight range and its absence in metaphase. This protein triplet most likely corresponds to the lamins A, B, and C of the nuclear lamina. The combined results suggest that the main difference in the structural organization of interphase nuclei and metaphase chromosomes is the presence or absence of the pore complex-lamina layer.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00285627
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Actin and RNA are components of the chromatoid bodies in spermatids of the rat (1984)
    Springer
    Cell & tissue research 236 (1984), S. 487-490 
    Details
    ISSN: 1432-0878
    Keywords: Spermatocytes ; Spermatids ; Chromatoid body ; Actin ; RNA ; Differentiation ; Immuno-electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Chromatoid bodies present in spermatocytes and spermatids of the rat show directed movements around spermatid nuclei during differentiation. This transient organelle contains RNA and establishes contact to intranuclear material and to the acrosomal complex. In order to determine possible components of motility and to verify the presence of RNA, we used a recently developed low-temperature embedding resin combined with protein A-gold and enzyme-gold techniques for studies at the ultrastructural level. All chromatoid bodies analyzed display high concentrations of gold particles over the electron-dense regions when labeled with antiactin. In contrast, RNase-gold particles were localized mainly in the electron-translucent areas. Corresponding controls were always negative. The results suggest a relationship between the impressive motility of the chromatoid body and actin present in the organelle. In addition, specific localization of RNA supports earlier findings that consider the chromatoid body an essential element for differentiation during spermiogenesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00214254
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Analysis of ring-shaped nucleoli in serially sectioned human lymphocytes (1983)
    Springer
    Cell & tissue research 234 (1983), S. 707-711 
    Details
    ISSN: 1432-0878
    Keywords: Lymphocyte ; Nucleoli ; Ribonucleoprotein ; Man
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Serial section analysis has demonstrated that ring-shaped nucleoli of mature human lymphocytes are spherical structures consisting of a peripheral ribonucleoprotein shell that surrounds one large fibrillar center. The shell exhibits usually one or, less frequently, two openings. The fibrillar center is in contact with the nucleoplasm and perinucleolar condensed chromatin, which frequently appears as a pedicle-like structure. Several chromocenters are associated with the ring-shaped nucleolus.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218661
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Ionic currents traverse growing hyphae and sporangia of the mycelial water moldAchlya debaryana (1983)
    Springer
    Protoplasma 115 (1983), S. 65-69 
    Details
    ISSN: 1615-6102
    Keywords: Achlya ; Development ; Electrophysiology ; Sporogenesis ; Vibrating probe
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary This study explores natural ionic currents traversing hyphae and sporangia during the asexual life cycle of the mycelial water moldAchlya debaryana. Ionic current enters the extending hyphal apex at a density of 1–2μAcm−2 in the form of current spikes. Current normal to the surface enters hyphae up to 600 μm behind the growing tip. A large efflux of current lasting 1–2 minutes occurs during the homogeneous stage of sporangium development. Spore release is accompanied by a few spikes of inward current. The results obtained so far suggest that the developmental processes of hyphal elongation and sporangium formation in the asexual life cycle of water molds are correlated with particular ionic currents.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01293582
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    facet.materialart.
    Unknown
    Analysis of ring-shaped nucleoli in serially sectioned human lymphocytes (1983)
    Springer
    Details
    Publication Date: 1983-12-01
    Print ISSN: 0302-766X
    Electronic ISSN: 1432-0878
    Topics: Biology , Medicine
    Published by Springer
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 7
    facet.materialart.
    Unknown
    Comparative studies on the structural organization of membrane-depleted nuclei and metaphase chromosomes (1983)
    Springer
    Details
    Publication Date: 1983-09-01
    Print ISSN: 0009-5915
    Electronic ISSN: 1432-0886
    Topics: Biology , Medicine
    Published by Springer
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...