ALBERT — All Library Books, journals and Electronic Records Telegrafenberg

Treffer pro Seite

Treffer 1 - 3 | 3 Treffer

Sortierung

Digitale Medien

The NADH-dependent Fe3+-chelate reductases of tomato roots (1997)

Bagnaresi, Paolo ; Basso, Barbara ; Pupillo, Paolo

Springer

Planta 202 (1997), S. 427-434

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1432-2048

Schlagwort(e): Key words: Fe3+-chelate reductase ; Ferricyanide re ductase ; Iron starvation ; Lycopersicon (Fe starvation)

Quelle: Springer Online Journal Archives 1860-2000

Thema: Biologie

Notizen: Abstract. The NADH-dependent Fe3+-chelate reductase (NFCHR) of tomato (Lycopersicon esculentum L.) roots, a strategy I species, was investigated. The Fe3+-citrate reductase (FeCitR) assay was strongly inhibited by p-hydroxymercuribenzoic acid (PHMB); moreover, the inhibitor was found to be more specific to the FeCitR assay than to the Fe3+-EDTA reductase assay, which was catalyzed by at least another reductase of 46 kDa. After high-speed centrifugation of tomato root membranes, high FeCitR activities were detected in pellets and lower activities in supernatants. After two-phase partitioning of microsomes, FeCitR activity (91 nmol · min−1 · mg−1) was less active in the upper phase (plasma membrane) than in the lower phase (277 nmol · min−1 · mg−1). However, only the activity of the plasma-membrane-associated NFCHR (FeCitR) was significantly enhanced (2.6-fold) in iron-deficient tomato plants, whereas that of NFCHR in non-plasma-membrane rich fractions was unaffected by this treatment. The NFCHR obtained from lysophosphatidylcholine-solubilized plasma membrane was present as a 200-kDa protein complex following fast protein liquid chromatography on Superdex 200, or as a 28-kDa form following Blue Sepharose CL-6B chromatography. Both preparations were more active following iron starvation. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the 28-kDa protein purified from solubilized tomato microsomes or supernatant fractions by a final Mono Q step consisted of a single band of 32 kDa. Tomato root NFCHR resembled the NFCHR of maize (a strategy II plant, P Bagnaresi and P Pupillo, 1995, J Exp Bot 46: 1497–1503) in several properties: relative molecular mass, hydrophilicity, chromatographic behaviour, sensitivity to mercurials, specificity for electron donors and acceptors (e.g. cytochrome c), and a ferricyanide reductase-to-FeCitR ratio of 2.5. Preincubation with NADH partially protected NFCHR from PHMB-induced inactivation. Our data show that strategy I and II plants seem to share similar NFCHR proteins, which appear to belong to the cytochrome b 5 reductase flavoprotein group.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1007/s004250050146

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

Digitale Medien

Distribution of transposable elements in neotropical species of Drosophila (1997)

da S. Loreto, E.L. ; Basso da Silva, L. ; Zaha, A. ; [weitere]

Springer

Genetica 101 (1997), S. 153-165

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1573-6857

Schlagwort(e): transposable elements ; Drosophila ; gypsy ; hobo ; P element ; mariner ; I element

Quelle: Springer Online Journal Archives 1860-2000

Thema: Biologie

Notizen: Abstract The phylogenetic distribution of transposable families, P, gypsy, hobo, I, and mariner has been analyzed in 33 species of 11 groups of neotropical Drosophila and a Drosophilidae species Zygotrica vittimaculosa, using squash blot and dot blot. Genomic DNA of almost all neotropical species tested hybridized with gypsy probe and some species showed a particularly strong hybridization signal, as D. gaucha, D. virilis, and species of flavopilosa group. The hobo element was restricted to melanogaster group and some strains of D. willistoni. Only D. simulans DNA showed hybridization to mariner probe in all species tested and D. simulans and D. melanogaster showed hybridization with I element probe. P element homologous sequence was present in D. melanogaster and all species and strains of the willistoni and saltans groups tested. The presence of at least one P-homologous sequence was detected in Drosophila mediopunctata. This one was the only P-bearing species of all six tested from the tripunctata group. Four different pairs of primers homologous to segments of the canonical sequence of D. melanogaster's P were used to amplify specific sequences from D. mediopunctata DNA, showing the occurrence of seemingly well-conserved P-homologous sequences.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1023/A:1018381104700

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

Unbekannt

Appetite-suppressing effects of urocortin, a CRF-related neuropeptide (1996)

M. Spina ; E. Merlo-Pich ; R. K. Chan ; [weitere]

American Association for the Advancement of Science (AAAS)

In: Science. 273(5281): 1561-4.

zur Merkliste hinzufügen auf der Merkliste

Details

Publikationsdatum: 1996-09-13

Beschreibung: The neuropeptide corticotropin-releasing factor (CRF) is well known to act on the central nervous system in ways that mimic stress and result in decreases in exploration, increases in sympathetic activity, decreases in parasympathetic outflow, and decreases in appetitive behavior. Urocortin, a neuropeptide related to CRF, binds with high affinity to the CRF2 receptor, is more potent than CRF in suppressing appetite, but is less potent than CRF in producing anxiety-like effects and activation. Doses as low as 10 nanograms injected intracerebroventricularly were effective in decreasing food intake in food-deprived and free-feeding rats. These results suggest that urocortin may be an endogenous CRF-like factor in the brain responsible for the effects of stress on appetite.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Spina, M -- Merlo-Pich, E -- Chan, R K -- Basso, A M -- Rivier, J -- Vale, W -- Koob, G F -- 1 F05 TW05262/TW/FIC NIH HHS/ -- DK 26741/DK/NIDDK NIH HHS/ -- New York, N.Y. -- Science. 1996 Sep 13;273(5281):1561-4.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Neuropharmacology, Scripps Research Institute, 10666 North Torrey Pines Road, La Jolla, CA 92037, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/8703220" target="_blank"〉PubMed〈/a〉

Schlagwort(e): Animals ; Appetite/*drug effects ; Appetite Depressants/administration & dosage/metabolism/*pharmacology ; Behavior, Animal/drug effects ; Blood Pressure/drug effects ; Carrier Proteins/metabolism ; Corticotropin-Releasing Hormone/administration & dosage/metabolism/*pharmacology ; Dose-Response Relationship, Drug ; Eating/drug effects ; Fasting ; Injections, Intraventricular ; Motor Activity/drug effects ; Rats ; Rats, Wistar ; Receptors, Corticotropin-Releasing Hormone/metabolism ; Urocortins ; Urotensins/pharmacology

Print ISSN: 0036-8075

Digitale ISSN: 1095-9203

Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik

Publiziert von American Association for the Advancement of Science (AAAS)

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

AKTUELLE ARTIKEL

S·F·X

Volltext

Treffer 1 - 3 | 3 Treffer