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11.
Rabbits were immunized with rat liver nuclear L-triiodothyronine (T3) receptor purified by preparative sodium dodecyl sulfate-polyacrylamide (SDS-PAGE) gel electrophoresis using bromoacetyl[125I]T3 as an affinity label. SDS-PAGE confirmed the presence of two receptor forms of the apparent molecular weights 57,000 and 45,000. We describe here a specific antibody, raised against the 57,000 receptor type, which reacts with both receptor forms as assessed by electroimmunoblotting and immunoprecipitation in liquid medium. 相似文献
12.
Genetic transformation of peppermint is known to be very difficult essentially because of low efficiency regeneration. A regeneration protocol allowing 51% shooting frequency is proposed. Transient -glucuronidase expression and adjustment of selection pressure with kanamycin are also reported. The final retained method to attempt peppermint transformation is:Agrobacterium inoculation or biolistic treatment of the first apical leaves ofin vitro clones, regeneration in the dark with kanamycin (1 mg l–1) and 6-benzylaminopurine (2 mg l–1), followed by selection of regenerated shoots with 200 mg 1–1 kanamycin.Abbreviations BA
6-benzylaminopurine
- GUS
-glucuronidase
- MS
Murashige and Skoog (1962)
- NAA
-naphthalenacetic acid
- PIG
particle inflow gun
- SEM
scanning electron microscope 相似文献
13.
Comparative effects of cholesterol and cholesterol sulfate on hydration and ordering of dimyristoylphosphatidylcholine membranes.
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The comparative effect of cholesterol (CH) versus cholesterol sulfate (CS) on dimyristoylphosphatidylcholine (DMPC) membranes has been investigated by optical microscopy, freeze-fracture electron microscopy, x-ray diffraction, and solid state 2H and 31P nuclear magnetic resonance (NMR). The sulfate analogue extends the lamellar phase domain toward high water contents, and substitution of 30 mol % CH by CS in DMPC lamellae induces the trapping of 30 wt % additional water. The greater swelling of the CS-containing systems is evidenced by determination of lamellar repeat distances at maximal hydration: 147 +/- 4 A and 64 +/- 2 A in the presence of CS and CH, respectively. 2H-NMR of heavy water demonstrates that CS binds approximately 12 more water molecules at the interface than CH whereas NMR of deuterium-labeled DMPC chains reveals that 30 mol % CS orders the membrane as 15 mol % CH at high temperature and disorders much more than CH at low temperatures. The various effects of CS versus CH are discussed by taking into account attractive Van der Waals forces and repulsive steric/electrostatic interactions of the negatively charged sulfate group. 相似文献
14.
I. Reguigne-Arnould S. Faure M. Chery L. Mota-Vieira R. Mollicone J.J. Candelier R. Oriol P. Couillin 《Genomics》1996,32(3):458
We have regionally localized 49 microsatellite markers developed by Généthon using a panel of previously characterized somatic cell hybrids that retain fragments from chromosome 19. The tight correlation observed between the physical and the genetic orders of the microsatellites provide cytogenetic anchorages to the genetic map data. We propose a position for the centromere just above D19S415, from the study of two hybrids, each of which retains one of the two derivatives of a balanced translocation t(1;19)(q11;q11). Microsatellites, which can be identified by a standard PCR protocol, are useful tools for the localization of disease genes and for the establishment of YAC or cosmid contigs. These markers can also judiciously be used for the characterization of new hybrid cell line panels. We report such a characterization of 11 clones, 8 of which were obtained by irradiation-fusion. Using the whole hybrid panel, we were able to define the order of 12 pairs of genetically colocalized microsatellites. As examples of gene mapping by the combined use of microsatellites and hybrid cell lines, we regionally assigned the PVS locus between the 19q13.2 markers D19S417 and D19S423 and confirmed the locations of fucosyltransferase loci FUT1, FUT2, and FUT5. 相似文献
15.
C. Faure N. Devauchelle J. -P. Girard 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1994,164(6):444-450
Fertilization of the scallopPecten maximus occurs after gametes were naturally released in sea water by the bivalve which has undergone stimulation. The motility of the spermatozoa requires their dilution in sea water (1/40). Dilution triggers an immediate increase of oxygen consumption by sperm, reflecting an activation of a cyanide-sensitive respiration of a cellular origin. When scallops were stimulated by thermal shocks or by serotonin injection, sperm sampled at the urogenital pore output duct shows a respiration-motility activation after sea water dilution which is not seen in sperm scarified from the gonad. Dilution of kidney-sampled sperm into acidic (pH 5) or Na+-free artificial sea water reversibly inhibits both respiration and motility. In all cases fertilization rate of sperm is correlated to the increase of respiratory rate and motility measured after dilution in different media. Whether the scallop was stimulated or not, the pH of haemolymph and pericardic fluids were one pH unit below the value of sea water, the pH of the gonad and of the kidney tissues being more acidic (6.5 in average). Our results suggest that the acidic pH of the genital tract maintains the spermatozoa in a quiescent state and that capacitation occurs when male gametes move from the gonad to the kidney from where it is naturally released.Abbreviations ASW
artificial sea water
- SW
sea water
- TRIS
trishydroxymethyl-aminomethane 相似文献
16.
Isolation of Azospirillum lipoferum 4T Tn5 Mutants Affected in Melanization and Laccase Activity 总被引:1,自引:0,他引:1
Azospirillum lipoferum 4T has original properties such as nonmotility, melanin synthesis, and laccase activity. Following random Tn5 mutagenesis in A. lipoferum 4T, we obtained 10 mutants which were affected in melanization and laccase activity. The class 1 mutants, with intermediate levels of laccase activity, showed some coloration; the class 2 mutants, which were completely negative for laccase activity, were also colorless. The Tn5 localization on the chromosome or on the cryptic 300-MDa plasmid of A. lipoferum 4T was proven by hybridization for all class 1 mutants or for most class 2 mutants, respectively. 相似文献
17.
Bouchra Harraki Pascale Guiraud Marie-Hélène Rochat Henri Faure Marie-Jeanne Richard Michelle Fussellier Alain Favier 《Biometals》1994,7(3):237-243
Radioactive zinc was used to study the effect of a binary parenteral nutrient solution, composed of amino acids and glucose, on zinc uptake by fibroblasts. The influence of addition of taurine, l-glutamine and of the increase in l-histidine content of the admixture was assessed. The pure mixture was highly toxic for cells and so it was diluted 1/5 in tyrode buffer with 2% albumin. As compared with cells incubated in the buffer containing albumin, zinc absorption was significantly higher (P < 0.05) in the presence of the amino acids of the mixture. Amino acids thus increased bioavailability by displacing zinc bound to albumin. When the histidine concentration in the nutrient medium (4.2 mm) was doubled, inhibition was noted after 30 min of incubation and zinc uptake thereafter remained comparable to that in histidine-free medium. The addition of glutamine (4.2 mm), usually not present in binary mixtures, resulted in significant differences as compared with glutamine-free control medium. Taurine (0.8 mm), led to a constant increase in zinc uptake by fibroblasts as compared with that obtained with taurine-free mixture. However, ultrafiltration showed that taurine was not able to displace zinc from albumin. 相似文献
18.
W. S. Hantoro P. A. Pirazzoli C. Jouannic H. Faure C. T. Hoang U. Radtke C. Causse M. Borel Best R. Lafont S. Bieda K. Lambeck 《Coral reefs (Online)》1994,13(4):215-223
A flight of six major coral reef terraces, up to 700 m in altitude, occurs along the eastern and northern sides of Kabola Peninsula, Alor Island, Indonesia. Some radiometric dates have been obtained from unrecrystallized coral samples collected in growth position by three different methods (14C, 230Th/234U, ESR). This enabled the identification of the terraces corresponding to the Holocene and to oxygen-isotope stages 5c, 5e and 7. According to the present elevation of the dated terraces, a 1.0–1.2 mm/y mean rate of uplift can be discerned. Extrapolation of this trend to the whole sequence of terraces reveals a good correlation between the development of major terraces and interglacial or interstadial stages corresponding to astronomically calibrated oxygen isotope records, up to stage 13. The relatively rapid uplift rate in this region minimized the possibility of polycyclic sea-level stands at the same levels and contributed to the good preservation of some morphological reef features. Two superimposed marine notches are visible near the present shoreline, with retreat points at about 5.0 m and 8.6 m respectively above the present MLWST level. They can be interpreted as corresponding to a glacial interstadial (the upper notch) and to the Holocene sea-level peak (the lower one). As Holocene emergence has been less than what could be expected from a 1 mm/y rate of uplift, a major coseismic vertical displacement may occur in the future.This work is a contribution to the IGCP Project 367 Late Quaternary coastal records of rapid change and to the activities of the INQUA Commissions Neotectonics and Shorelines, the task group Paleoseismicity of the Late Holocene of the Inter-Union Commission on the Lithosphere, and the UNESCO-IUGS cooperative programme Earth Processes in Global Change (CLIP Pilot Project) 相似文献
19.
In Xenopus laevis, the product of a developmentally regulated mRNA is structurally and functionally homologous to a Saccharomyces cerevisiae protein involved in translation fidelity. 总被引:7,自引:1,他引:6
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J P Tassan K Le Guellec M Kress M Faure J Camonis M Jacquet M Philippe 《Molecular and cellular biology》1993,13(5):2815-2821
We have performed a differential screen of a Xenopus egg cDNA library and selected two clones (Cl1 and Cl2) corresponding to mRNA which are specifically adenylated and recruited into polysomes after fertilization. Sequence analysis of Cl1 reveals that the corresponding protein is 67.5% identical (83% similar) to the product of the Saccharomyces cerevisiae SUP45 (also called SUP1 or SAL4) gene. This gene, when mutated, is an omnipotent suppressor of nonsense codons. When expressed in a sup45 mutant, the Xenopus Cl1 cDNA was able to suppress sup45-related phenotypes, showing that the structural homology reflects a functional homology. Our discovery of a structural and functional homolog in Xenopus cells implies that the function of SUP45 is not restricted to lower eukaryotes and that the SUP45 protein may perform a crucial cellular function in higher eukaryotes. 相似文献
20.
Laetitia Mathon Virginie Marques Stéphanie Manel Camille Albouy Marco Andrello Emilie Boulanger Julie Deter Régis Hocdé Fabien Leprieur Tom B. Letessier Nicolas Loiseau Eva Maire Alice Valentini Laurent Vigliola Florian Baletaud Sandra Bessudo Tony Dejean Nadia Faure Pierre-Edouard Guerin Meret Jucker Jean-Baptiste Juhel Kadarusman Andrea Polanco F. Laurent Pouyaud Dario Schwörer Kirsten F. Thompson Marc Troussellier Hagi Yulia Sugeha Laure Velez Xiaowei Zhang Wenjun Zhong Loïc Pellissier David Mouillot 《Global Ecology and Biogeography》2023,32(8):1336-1352