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
Filter
  • Transcription  (2)
  • Key words: Aquaporin  (1)
  • Metallacycles  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Desiccation and osmotic stress increase the abundance of mRNA of the tonoplast aquaporin BobTIP26-1 in cauliflower cells (1999)
    Springer
    Planta 209 (1999), S. 77-86 
    Details
    ISSN: 1432-2048
    Keywords: Key words: Aquaporin ; Brassica (cauliflower) ; Gene regulation ; Tonoplast ; Vacuole ; Water stress
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract. Changes in vacuolar structure and the expression at the RNA level of a tonoplast aquaporin (BobTIP26-1) were examined in cauliflower (Brassicaoleracea L. var. botrytis) under water-stress conditions. Gradual drying out of slices of cauliflower floret tissue caused its collapse, with a shrinkage in tissue and cell volumes and an apparent vesiculation of the central vacuole, whereas osmotic stress resulted in plasmolysis with a collapse of the cytoplasm and the central vacuole within. Osmotic stress caused a rapid and substantial increase in BobTIP26 mRNA in slices of floret tissue. Exposure of tissue slices to a regime of desiccation showed a slower but equally large rise in BobTIP26 mRNA followed by a rapid decline upon rehydration. In situ hybridization showed that BobTIP26-2 mRNA is expressed most highly in meristematic and expanding cells of the cauliflower florets and that desiccation strongly increased the expression in those cells and in differentiated cells near the xylem vessels. These data indicate that under water-deficit conditions, expression of the tonoplast aquaporin gene in cauliflower is subject to a precise regulation that can be correlated with important cytological changes in the cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004250050608
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    The vacuolar compartment is required for sulfur amino acid homeostasis inSaccharomyces cerevisiae (1994)
    Springer
    Molecular genetics and genomics 244 (1994), S. 519-529 
    Details
    ISSN: 1617-4623
    Keywords: Sulfur metabolism ; Vacuolar biogenesis ; Transcription
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In order to isolate new mutations impairing transcriptional regulation of sulfur metabolism inSaccharomyces cerevisiae, we used a potent genetic screen based on a gene fusion expressing XylE (fromPseudomonas putida) under the control of the promoter region ofMET25. This selection yielded strains mutated in various different genes. We describe in this paper the properties of one of them,MET27. Mutation or disruption ofMET27 leads to a methionine requirement and affects S-adenosylmethionine (AdoMet)-mediated transcriptional control of genes involved in sulfur metabolism. The cloning and sequencing ofMET27 showed that it is identical toVPS33. Disruptions or mutations of geneVPS33 are well known to impair the biogenesis and inheritance of the vacuolar compartment. However, the methionine requirement ofvps33 mutants has not been reported previously. We show here, moreover, that other vps mutants of class C (no apparent vacuoles) also require methionine for growth. Northern blotting experiments revealed that themet27-1 mutation delayed derepression of the transcription of genes involved in sulfur metabolism. By contrast, this delay was not observed in amet27 disrupted strain. Physiological and morphological analyses ofmet27-1 andmet27 disrupted strains showed that these results could be explained by alterations in the ability of the vacuole to transport or store AdoMet, the physiological effector of the transcriptional regulation of sulfur metabolism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00583903
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    The synthesis of the two S-adenosyl-methionine synthetases is differently regulated in Saccharomyces cerevisiae (1991)
    Springer
    Molecular genetics and genomics 226 (1991), S. 224-232 
    Details
    ISSN: 1617-4623
    Keywords: Saccharomyces cerevisiae ; SAM1 and SAM2 genes ; Transcription
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary S-adenosyl-l-methionine (AdoMet) is synthesized by transfer of the adenosyl moiety of ATP to the sulfur atom of methionine. This reaction is catalysed by AdoMet synthetase. In all eukaryotic organisms studied so far, multiple forms of AdoMet synthetases have been reported and from their recent study, it appears that AdoMet synthetase is an exceptionally well conserved enzyme through evolution. In Saccharomyces cerevisiae, we have demonstrated the existence of two AdoMet synthetases encoded by genes SAM1 and SAM2. Yeast, which is able to concentrate exogenously added AdoMet, is thus a particularly useful biological system to understand the role and the physiological significance of the preservation of two almost identical AdoMet synthetases. The analysis of the expression of the two SAM genes in different genetic backgrounds during growth under different conditions shows that the expression of SAM1 and SAM2 is regulated differently. The regulation of SAM1 expression is identical to that of other genes implicated in AdoMet metabolism, where as SAM2 shows a specific pattern of regulation. A careful analysis of the expression of the two genes and of the variations in the methionine and AdoMet intracellular pools during the growth of different strains lead us to postulate the existence of two different AdoMet pools, each one suppplied by a different AdoMet synthetase but in equilibrium with each other. This could be a means of storing AdoMet whenever this metabolite is overproduced, thus avoiding the degradation of a metabolite the synthesis of which is energetically expensive.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00273607
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Untypical Regioselectivity of Carbon Dioxide Coupling with Titanocene Complexes of Phenyl(trimethylsilyl)acetylene by Using the meso-1,2-Ethylene-1,1′-bis(η5-tetrahydroindenyl) Ligand System (1998)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 1998 (1998), S. 1495-1502 
    Details
    ISSN: 1434-1948
    Keywords: Alkyne complexes ; Titanium ; ansa-Metallocenes ; Carbon dioxide fixation ; C-C coupling ; Metallacycles ; Regioselectivity ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of [meso-(ebthi)TiCl2] [ebthi = 1,2-ethylene-1,1′-bis(η5-tetrahydroindenyl)] with magnesium in the presence of the alkynes Me3SiC≡CSiMe3 and PhC≡CSiMe3 resulted in the formation of the complexes [meso-(ebthi)Ti(η2-Me3SiC2SiMe3)] (1) and [meso-(ebthi)Ti(η2-PhC2SiMe3)] (2a and 2b), which were isolated and then characterized by their NMR spectra. Due to incomplete reduction the TiIII complex [meso-(ebthi)Ti(THF)Cl] (3) was also obtained as a by-product of these reactions. By insertion into the Ti-CPh bond carbon dioxide reacted with the titanacyclopropene structure of the alkyne complex [meso-(ebthi)Ti(η2-PhC2SiMe3)] (2a), with untypical regioselectivity to yield the α-silyl-substituted meso-(ebthi)titanafuranone 6a. In the analogous reactions of the complexes [(thi)2Ti(η2-PhC2SiMe3)] (thi = η5-tetrahydroindenyl), [rac-(ebthi)Ti(η2-PhC2SiMe3)], and [Cp*2Ti(η2-PhC2SiMe3)] with carbon dioxide typical regioselectivity (insertion into the M-CSi bond of the titanacyclopropene) was observed, yielding the β-silyl-substituted titanafuranones 7, 8a, and 9. These results show that insertion of carbon dioxide into the M-C bond of the titanacyclopropene structure of the alkynemetallocene complexes is governed by the substitution pattern of the alkyne and the steric enviroment around the metal center. The complexes 3, 6a, and 7 were investigated by X-ray crystal structure analysis.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...