Library

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
    Secretogranin II: Regulation of Synthesis and Post-Translational Proteolysis in Bovine Adrenal Chromaffin Cells (1993)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neuroendocrinology 5 (1993), S. 0 
    Details
    ISSN: 1365-2826
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Secretogranin M (Sgll), also called chromogranin C, is an acidic tyrosine-sulfated secretory protein found in secretory granules in a wide variety of endocrine cells and neurones. Although less abundant than chromogranin A (CGA) and chromogranin B (CGB), Sgll is found in adrenal medullary chromaffin granules. In the present study we investigated the regulation of Sgll biosynthesis in bovine chromaffin cells maintained in primary culture. Cellular proteins were labelled with [35S]methionine and the heat stable chromogranin enriched fraction was isolated. Following electrophoretic separation, the 86 kDa Sgll band was identified by sequence analysis using the Edman degradation procedure. The radioactivity incorporated in the 86 kDa Sgll band was used as an index of the Sgll synthesis rate. We found that stimulation of chromaffin cells with nicotine and histamine and to a smaller extent with angiotensin II and bradykinin significantly enhanced the rate of Sgll synthesis. In contrast direct depolarization with K+ had no effect on Sgll synthesis suggesting that the raise of cytosolic calcium evoked by high K+ may not be sufficient to induce modifications in Sgll synthesis. The possible second messenger pathways involved in the control of Sgll biosynthesis were investigated by using protein kinase C and adenylate cyclase activators. We observed that 12-O-tetradecanoylphorbol 13-acetate (TPA) and forskolin increased the basal rate of Sgll synthesis. Incubation with both TPA and forskolin was required to obtain an effect comparable to that produced by nicotine or histamine suggesting that these secretagogues recruit both protein kinase C- and cyclic AMP-dependent mechanisms to stimulate Sgll synthesis. Our results indicate that within chromaffin granules, the rates of CGA, CGB and Sgll synthesis are independently regulated and suggest a close relationship between the cell secretory activity and the biosynthesis of Sgll.The biological role of Sgll is unknown but it has been suggested that the protein may function as a precursor of potentially bioactive peptides. Here we identified a Sgll derived peptide corresponding to the C-terminal residues 582–586 in the soluble core of purified chromaffin granules. This peptide was released together with catecholamines upon stimulation of cultured chromaffin cells indicating that the peptide was present within the storage complex of chromaffin granules and was not the result of some artefactual proteolytic degradation of Sgll during the course of granule purification. We propose that this peptide is a specific product of the post-translational processing of Sgll. By analogy with peptides derived from CGA and CGB, it may possess some specific biological activity that remains to be identified.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2826.1993.tb00536.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Antibacterial Peptides Are Present in Chromaffin Cell Secretory Granules (1998)
    Springer
    Cellular and molecular neurobiology 18 (1998), S. 249-266 
    Details
    ISSN: 1573-6830
    Keywords: antibacterial peptides ; chromaffin cells ; secretory granules ; chromogranins ; proenkephalin A
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract 1. Antibacterial activity has recently been associated with the soluble matrix of bovine chromaffin granules. Furthermore, this activity was detected in the contents secreted from cultured chromaffin cells following stimulation. 2. The agents responsible for the inhibition of Gram+ and Gram− bacteria growth are granular peptides acting in the micromolar range or below. In secretory granules, these peptides are generated from cleavage of chromogranins and proenkephalin A and are released together with catecholamines into the circulation. 3. Secretolytin and enkelytin are the best characterized; these two peptides share sequence homology and similar antibacterial activity with insect cecropins and intestinal diazepam-binding inhibitor. For some of the peptides derived from chromogranin A, posttranslational modifications were essential since antibacterial activity was expressed only when peptides were phosphorylated and/or glycosylated. 4. The significance of this activity is not yet understood. It may be reminiscent of some primitive defense mechanism or may serve as a first barrier to bacteria infection during stress, as these peptides are secreted along with catecholamines.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1022573004910
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Isolation of a complementary DNA encoding the bean PR4 chitinase: an acidic enzyme with an amino-terminus cysteine-rich domain (1991)
    Springer
    Plant molecular biology 17 (1991), S. 243-253 
    Details
    ISSN: 1573-5028
    Keywords: bean chitinase cDNA ; cysteine-rich domain ; plant defence ; chemical stress
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The amino acid sequences of peptides generated by trypsin and chymotrypsin digestions of the acidic PR4 chitinase from bean were determined. Oligonucleotide primers derived from this sequence were used to synthesize a PR4 chitinase-specific probe by PCR-amplification. This probe allowed the isolation of cDNA clones encoding PR4 chitinase that have been sequenced. This acidic and extracellular chitinase shows some homology to the basic isoform from the same plant, and differs from other known acidic chitinases by the presence of an amino-terminal cysteine-rich domain. Southern blot analysis of bean genomic DNA revealed that PR4 chitinase is encoded by a single gene.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00039499
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Structural and biochemical properties of kinesin heavy chain associated with rat brain mitochondria (1994)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 28 (1994), S. 79-93 
    Details
    ISSN: 0886-1544
    Keywords: kinesin ; brain mitochondria ; motility ; membrane-associated ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Kinesin, a mechanochemical enzyme that translocates membranous organelles, was initially identified and purified from soluble extracts from vertebrate brains. However, immunocytochemical and morphological approaches have demonstrated that kinesin could be associated to intracellular membranous organelles. We used an antibody raised against the head portion of the Drosophila kinesin heavy chain to reveal the presence of this protein in membranous organelles from rat brain. By using differential centrifugation and immunoblotting we observed a 116 kDa protein that crossreacts with this antibody in microsomes, synaptic vesicles, and mitochondria. This protein could be extracted from mitochondria with low salt concentrations or ATP. The 116 kDa solubilized protein has been identified as conventional kinesin based on limited sequence analysis. We also show that a polyclonal antibody raised against mitochondria-associated kinesin recognizes soluble bovine brain kinesin. The soluble and mitochondrial membrane-associated kinesins show a different isoform pattern. These results are consistent with the idea that kinesin exists as multiple isoforms that might be differentially distributed within the cell. In addition digitonin fractionation of mitochondria combined with KI extraction revealed that kinesin is a peripheral protein, preferentially located in a cholesterol-free outer membrane domain; this domain has the features of contact points between the mitochondrial outer and inner membranes. The significance of these observations on the functional regulation of the mitochondria-associated kinesin is discussed. © 1994 Wiley-Liss, Inc.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970280108
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...