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
    Ca2+-sensitive isolation of a cortical actin matrix fromDictyostelium amoebae (1983)
    Springer
    Journal of muscle research and cell motility 4 (1983), S. 115-131 
    Details
    ISSN: 1573-2657
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A cortical actin matrix has been isolated from amoebae ofDictyostelium discoideum grown in liquid culture. The existence of this actin matrix in whole cells is indicated in electron micrographs as an area free of cytoplasmic organelles. The actin beneath the membrane is more clearly visible in sections of cells that are lysed gently with 0.5% Triton X-100 and fixed with 1% glutaraldehyde. Such Triton-lysed cells have fragments of plasma membrane associated with the cortical actin matrix. Isolation of the actin matrix, which sediments at 400g, is inhibited by Ca2+. As much as 50% of the actin of the cell and about 12% of the total protein is found in the matrix isolated in lysis buffer containing no added Ca2+ and 2.5mm EGTA, whereas less than 15% of the actin of the cell is recovered in a 400g pellet when cells are lysed in buffer containing 2.5mm Ca2+ and 2.5mm EGTA. A 40 000 molecular weight protein that fragments F-actin in a Ca2+-dependent manner is not found in the isolated cortical actin matrix.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00711962
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Unfertilized sea urchin eggs contain a discrete cortical shell of actin that is subdivided into two organizational states (1988)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 9 (1988), S. 85-96 
    Details
    ISSN: 0886-1544
    Keywords: fertilization ; echinoderm eggs ; egg cortex ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Changes in the distribution and organizational state of actin in the cortex of echinoderm eggs are believed to be important events following fertilization. To examine the initial distribution and form of actin in unfertilized eggs, we have adapted immunogold-labeling procedures for use with eggs of Strongylocentrotus purpuratus. Using these procedures, as well as fluorescence microscopy, we have revealed a discrete 1-μm-thick concentrated shell of actin in the unfertilized egg cortex. This actin is located in the short surface projections of unfertilized eggs and around the cortical granules in a manner that suggests it is associated with the cortical granule surface. The actin in the short surface projections appears to be organized into filaments. However, most if not all of the actin surrounding the cortical granules is organized in a form that does not bind phalloidin, even though it is accessible to actin antibody. The lack of phalloidin binding is consistent with either the presence of nonfilamentous actin associated with the cortical granules or the masking of actin-filament phalloidin-binding sites by some cellular actin-binding component. In addition to the concentrated shell of actin found in the cortex, actin was also found to be concentrated in the nuclei of unfertilized eggs.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970090109
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Association of the β isoform of protein kinase C with vimentin filaments (1992)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 22 (1992), S. 250-256 
    Details
    ISSN: 0886-1544
    Keywords: cytoskeletal localization ; signal transduction ; intermediate filaments ; rat basophilic leukemia cells ; translocation ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Protein kinase C (PKC) isoforms are key mediators in hormone, growth factor, and neurotransmitter triggered pathways of cell activation (Nishizuka: Science 233:305-312, 1986; Nature 334:661-665, 1988). Stimulation of kinase activity by diacylglycerol and calcium often leads to translocation of PKC from the cytosol to a particulate fraction (Kraft and Anderson: Nature 301:621-623, 1983). The β isoform of PKC is translocated and degraded much more rapidly than the β isoform in phorbolester-stimulated rat basophilic leukemia (RBL) cells (Huang et al.: J. Biol. Chem. 264:4238-4243, 1989). We report here immunofluorescence evidence that the distributions of PKC α and β are strikingly different in antigen-activated RBL cells. PKC β associates with perinuclear filaments and filaments that extend from the perinuclear area to the cell periphery whereas PKC β concentrates in regions of the cell periphery. This distribution of PKC β is distinctly different from that of actin filaments and microtubules as determined by phalloidin staining and by anti-tubulin antibody labeling. In contrast, the staining patterns obtained with antibodies to PKC β and to the intermediate filament protein vimentin are almost identical, indicating that PKC β associates with vimentin filaments. These bundles of 100 Å filaments may provide docking sites for interactions of PKC β with its substrates and thus confer specificity to the actions of this isoform. © 1992 Wiley-Liss, Inc.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970220405
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Myosin reorganization in activated RBL cells correlates temporally with stimulated secretion (1994)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 29 (1994), S. 345-353 
    Details
    ISSN: 0886-1544
    Keywords: IgE receptors ; receptor activation ; myosin II phosphorylation ; PKC ; RBL 2H3 cells ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Rat basophilic leukemia cells secrete histamine and serotonin in response to cross-linking of the IgE receptor by multivalent antigen [Metzger et al., 1986: Ann. Rev. Immunol. 4:419-470]. Receptor crosslinking also induces phosphorylation of the light and heavy chains of myosin II with kinetics similar to that of secretion [Ludowyke et al., 1989: J. Biol. Chem. 264:12492-12501]. Here we show that myosin II localization changes after activation with similar kinetics. Furthermore, these changes are coincident with changes in cell shape and increase in motile activity induced by activation. Within 2 min, activated cells begin to flatten, spread on their substratum, and extend lamellipodia which show active ruffling. Quantitation of the extent of cell spreading from video micrographs shows that 48% of the cells increase significantly in surface area by 5 min and 71% by 15 min. Myosin II is uniformly distributed in unactivated cells but is deficient in newly formed lamellipodia that start to appear at 2 min after activation. In contrast these lamellipodia show strong staining for actin. Further changes in myosin organization are detected by 15 min after activation when myosin reappears in the cell periphery, is concentrated in the perinuclear area, and is also organized in punctate linear arrays that extend from the nucleus to the cell periphery. The kinetics of the early cell shape changes and formation of the myosin-deficient lamellipodia correlate well with, and may relate to, the increase in the level of myosin II phosphorylation reported by Ludowyke et al. [1989: J. Biol. Chem. 264:12492-12501]. Changes in the distribution of cell surface-bound IgE also occur upon antigen activation, and they correlate with the myosin distribution in a manner that suggests that they may be driven by myosin II. © 1994 Wiley-Liss, Inc.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970290407
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    facet.materialart.
    Unknown
    The Myosin Family of Mechanoenzymes: From Mechanisms to Therapeutic Approaches (2020)
    Annual Reviews
    Details
    Publication Date: 2020-06-20
    Description: Myosins are among the most fascinating enzymes in biology. As extremely allosteric chemomechanical molecular machines, myosins are involved in myriad pivotal cellular functions and are frequently sites of mutations leading to disease phenotypes. Human β-cardiac myosin has proved to be an excellent target for small-molecule therapeutics for heart muscle diseases, and, as we describe here, other myosin family members are likely to be potentially unique targets for treating other diseases as well. The first part of this review focuses on how myosins convert the chemical energy of ATP hydrolysis into mechanical movement, followed by a description of existing therapeutic approaches to target human β-cardiac myosin. The next section focuses on the possibility of targeting nonmuscle members of the human myosin family for several diseases. We end the review by describing the roles of myosin in parasites and the therapeutic potential of targeting them to block parasitic invasion of their hosts.
    Print ISSN: 0066-4154
    Electronic ISSN: 1545-4509
    Topics: Biology , Chemistry and Pharmacology
    Published by Annual Reviews
    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...