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
    Excitation and inhibition of rat medial vestibular nucleus neurones by 5-hydroxytryptamine (1993)
    Springer
    Experimental brain research 93 (1993), S. 293-298 
    Details
    ISSN: 1432-1106
    Keywords: Medial vestibular nucleus ; 5-Hydroxytryptamine ; Serotonin ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The effects of 5-hydroxytryptamine (5-HT) and related compounds on the discharge rate of tonically active medial vestibular nucleus (MVN) neurones were studied in an in vitro slice preparation of the dorsal brainstem of the rat. The majority (87 of 107, 82%) of MVN neurones were excited by 5-HT. Nine cells (8%) showed a biphasic response to 5-HT, which consisted of a brief inhibition followed by excitation. Eleven cells (10%) were inhibited by 5-HT. The excitatory effects of 5-HT were mimicked by alpha-methyl-5-HT and antagonised by ketanserin and ritanserin, indicating the involvement of the 5-HT2 subtype of 5-HT receptor. In biphasic cells, blockade of 5-HT2 receptors by ketanserin reduced the excitatory component of the response and revealed an enhanced initial inhibition. The inhibitory effects in biphasic cells, and in cells that showed a pure inhibition in response to 5-HT, were blocked by pindobind-5-HT and mimicked by 8-hydroxy-2-(di-n-propylamino)-tetralin indicating the involvement of 5-HT1A receptors. The significance of these findings in relation to the effects of 5-HT on vestibular reflex function is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00228397
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Appearance of a novel form of plant glutamine synthetase during nodule development in Phaseolus vulgaris L. (1983)
    Springer
    Planta 157 (1983), S. 254-258 
    Details
    ISSN: 1432-2048
    Keywords: Glutamine synthetase ; Leghaemoglobin ; Nitrogenase ; Nitrogen fixation ; Phaseolus ; Rhizobium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The activities of glutamine synthetase (GS), nitrogenase and leghaemoglobin were measured during nodule development in Phaseolus vulgaris infected with wild-type or two non-fixing (Fix-) mutants of Rhizobium phaseoli. The large increase in GS activity which was observed during nodulation with the wild-type rhizobial strain occurred concomitantly with the detection and increase in activity of nitrogenase and the amount of leghaemoglobin. Moreover, this increase in GS was found to be due entirely to the appearance of a novel form of the enzyme (GSn1) in the nodule. The activity of the form (GSn2) similar to the root enzyme (GSr) remained constant throughout the experiment. In nodules produced by infection with the two mutant strains of Rhizobium phaseoli (JL15 and JL19) only trace amounts of GSn1 and leghaemoglobin were detected.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00405190
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    A mutation that blocks exopolysaccharide synthesis prevents nodulation of peas by Rhizobium leguminosarum but not of beans by R. phaseoli and is corrected by cloned DNA from Rhizobium or the phytopathogen Xanthomonas (1986)
    Springer
    Molecular genetics and genomics 203 (1986), S. 320-323 
    Details
    ISSN: 1617-4623
    Keywords: Exopolysaccharide ; Legume ; Nodules ; Rhizobium ; Xanthomonas
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A Tn5-induced mutant strain of R. phaseoli which failed to synthesize exopolysaccharide (EPS) was isolated and was shown to induce normal nitrogen-fixing nodules on Phaseolus beans, the host of this Rhizobium species. The corresponding wild-type Rhizobium DNA was cloned in a wide host-range vector and by isolating Tn5 insertions in this cloned DNA, mutations in a gene termed pss (polysaccharide synthesis) were isolated. These were introduced by marker exchange into near-isogenic strains of R. leguminosarum and R. phaseoli which differed only in the identity of their symbiotic plasmids. Whereas the EPS-deficient mutant strain of R. phaseoli induced normal nitrogen-fixing nodules on Phaseolus beans, the same mutation prevented nodulation of peas by a strain of R. leguminosarum which normally nodulates this host. Further, it was found that DNA cloned from the plant pathogen Xanthomonas campestris pathover campestris could correct the defect in EPS synthesis in R. leguminosarum and R. phaseoli and also restored the ability to nodulate peas to the pss::Tn5 mutant strain of R. leguminosarum.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00333974
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Sequence of psi, a gene on the symbiotic plasmid of Rhizobium phaseoli which inhibits exopolysaccharide synthesis and nodulation and demonstration that its transcription is inhibited by psr, another gene on the symbiotic plasmid (1987)
    Springer
    Molecular genetics and genomics 207 (1987), S. 149-154 
    Details
    ISSN: 1617-4623
    Keywords: Beans ; DNA Sequence ; Gene regulation ; Nitrogen fixation ; Nodulation ; Rhizobium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A gene termed psi (polysaccharide inhibition), located close to the nodulation genes of the Rhizobium phaseoli symbiotic plasmid pRP2JI inhibited exopolysaccharide synthesis (EPS) and nodulation ability (Nod) in Rhizobium when it was cloned in a multicopy plasmid. The sequence of psi showed that it specified a polypeptide of mol. wt. 10000 that may be associated with the membrane of Rhizobium. A second gene, psr (polysaccharide restoration), was located on pRP2JI. When cloned in multicopy plasmids, psr overcame the EPS and Nod defects in strains carrying multicopy psi. Strains with multicopy psr induced non-fixing nodules on Phaseolus beans. Using gene fusions between psi and lacZ, it was shown that psi inhibited transcription of psr.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00331502
    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...