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41.
Giancola S Marhadour S Desloire S Clouet V Falentin-Guyomarc'h H Laloui W Falentin C Pelletier G Renard M Bendahmane A Delourme R Budar F 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2003,107(8):1442-1451
The radish Rfo gene restores male fertility in radish or rapeseed plants carrying Ogura cytoplasmic male-sterility. This system was first discovered in radish and was transferred to rapeseed for the production of F1 hybrid seeds. We aimed to identify the region of the Arabidopsis genome syntenic to the Rfo locus and to characterize the radish introgression in restored rapeseed. We used two methods: amplified consensus genetic markers (ACGMs) in restored rapeseed plants and construction of a precise genetic map around the Rfo gene in a segregating radish population. The use of ACGMs made it possible to detect radish orthologs of Arabidopsis genes in the restored rapeseed genome. We identified radish genes, linked to Rfo in rapeseed and whose orthologs in Arabidopsis are carried by chromosomes 1, 4 and 5. This indicates several breaks in colinearity between radish and Arabidopsis genomes in this region. We determined the positions of markers relative to each other and to the Rfo gene, using the progeny of a rapeseed plant with unstable meiotic transmission of the radish introgression. This enabled us to produce a schematic diagram of the radish introgression in rapeseed. Markers which could be mapped both on radish and restored rapeseed indicate that at least 50 cM of the radish genome is integrated in restored rapeseed. Using markers closely linked to the Rfo gene in rapeseed and radish, we identified a contig spanning six bacterial artificial chromosome (BAC) clones on Arabidopsis chromosome 1, which is likely to carry the orthologous Rfo gene.Electronic Supplementary Material Supplementary material is available in the online version of this article at Communicated by H. C. BeckerS. Giancola and S. Marhadour contributed equally to this work 相似文献
42.
Labarrère P Chatenet D Leprince J Marionneau C Loirand G Tonon MC Dubessy C Scalbert E Pfeiffer B Renard P Calas B Pacaud P Vaudry H 《Journal of enzyme inhibition and medicinal chemistry》2003,18(2):77-88
The sequence of human urotensin II (UII) has been recently established as H-Glu-Thr-Pro-Asp-Cys-Phe-Trp-Lys-Tyr-Cys-Val-OH, and it has been reported that UII is the most potent mammalian vasoconstrictor peptide identified so far. A series of UII analogues was synthesized, and the contractile activity of each compound was studied in vitro using de-endothelialised rat aortic rings. Replacement of each amino acid by an L-alanine or by a D-isomer showed that the N- and C-terminal residues flanking the cyclic region of the amidated peptide were relatively tolerant to substitution. Conversely, replacement of any residue of the cyclic region significantly reduced the contractile activity of the molecule. The octapeptide UII(4-11) was 4 times more potent than UII, indicating that the C-terminal region of the molecule possesses full biological activity. Alanine or D-isomer substitutions in UII(4-11) or in UII(4-11)-NH2, respectively, showed a good correlation with the results obtained for UII-NH2. Disulfide bridge disruption or replacement of the cysteine residues by their D-enantiomers markedly reduced the vasoconstrictor effect of UII and its analogues. In contrast, acetylation of the N-terminal residue of UII and UII-NH2 enhanced the potency of the peptide. Finally, monoiodination of the Tyr6 residue in UII(4-11) increased by 5 fold the potency of the peptide in the aortic ring bioassay. This structure-activity relationship study should provide useful information for the rational design of selective and potent UII receptor agonists and antagonists. 相似文献
43.
Chabane H Lamazzi C Thiery V Pierre A Leonce S Pfeiffer B Renard P Guillaumet G Besson T 《Journal of enzyme inhibition and medicinal chemistry》2003,18(2):167-174
Novel thiazolocarbazole derivatives have been synthesized via the corresponding imino-1,2,3-dithiazoles. In vitro antitumor activity of these polyheterocyclic compounds was studied. 相似文献
44.
Charton I Suzenet F Boutin JA Audinot V Delagrange P Bennejean C Renard P Guillaumet G 《Journal of enzyme inhibition and medicinal chemistry》2003,18(2):187-193
The synthesis of benzoxathiins bearing a retroamide function is described from 8-hydroxythiochroman, the key step involving the synthesis of the benzoxathiin ring through a sulfonium salt. These new melatonin analogues were evaluated on human receptors MT1 and MT2 and have a similar affinity to that of melatonin itself. 相似文献
45.
Braud E Duflos M Nourrisson MR Tonnerre A Picot C Le Baut G Renard P Pfeiffer B Tucker G 《Journal of enzyme inhibition and medicinal chemistry》2003,18(3):243-252
The synthesis and pharmacological evaluation of new 3-(imidazol-4(5)-ylmethylene)indolin-2-ones, analogues of SU-5416, are reported. The final compounds 20-51 were obtained by Knoevenagel coupling between the substituted indolin-2-ones 1-15 and either the formylimidazole derivatives 16-18 or 2-formyl-3,5-dimethylpyrrole 19. Methylation at the nitrogen atom of the indolin-2-one and/or imidazole moities was carried out in the presence of the couple NaH/DMF. A Mannich reaction afforded the 1-dimethylaminomethyl derivatives 43 and 48. The antiangiogenic activity of these compounds was evaluated in a three dimensional in vitro rat aortic ring assay. In this test, compound 20 induced a decrease of angiogenesis comparable to that observed with SU-5416; the vascular density indexes at 1 microM were 30 +/- 18 and 22 +/- 4% of control, respectively. The compounds were also evaluated, in an independent manner, as inhibitors of the human EGF-receptor tyrosine kinase activity. As expected, only minor activities were observed with four compounds, out of thirty-one, exerting inhibitory effects in the range of 40-55% at 10 microM concentration. 相似文献
46.
Xuemei?Li Ziyi?Li Alice?Jouneau Qi?ZhouEmail author Jean-Paul?Renard 《Reproductive biology and endocrinology : RB&E》2003,1(1):84
Cloning mammals by nuclear transfer is a powerful technique that is quickly advancing the development of genetically defined
animal models. However, the overall efficiency of nuclear transfer is still very low and several hurdles remain before the
power of this technique will be fully harnessed. Among these hurdles include an incomplete understanding of biologic processes
that control epigenetic reprogramming of the donor genome following nuclear transfer. Incomplete epigenetic reprogramming
is considered the major cause of the developmental failure of cloned embryos and is frequently associated with the disregulation
of specific genes. At present, little is known about the developmental mechanism of reconstructed embryos. Therefore, screening
strategies to design nuclear transfer protocols that will mimic the epigenetic remodeling occurring in normal embryos and
identifying molecular parameters that can assess the developmental potential of pre-implantation embryos are becoming increasingly
important. A crucial need at present is to understand the molecular events required for efficient reprogramming of donor genomes
after nuclear transfer. This knowledge will help to identify the molecular basis of developmental defects seen in cloned embryos
and provide methods for circumventing such problems associated with cloning the future application of this technology. 相似文献
47.
A simplified method for the reconstruction of fully competent mouse zygotes from adult somatic donor nuclei 总被引:18,自引:0,他引:18
Until now, full-term development of mouse embryos reconstructed from somatic nuclei has been convincingly achieved only when a piezoimpact pipette drive unit is used for the injection of a donor nucleus into an enucleated recipient oocyte. Here we describe a simplified method for mouse cloning that requires neither electrofusion nor a piezo device. Efficient rates of enucleation can be achieved without staining the chromosomes of the recipient oocyte and high survival rates are obtained after direct injection of the donor nucleus. Although a low proportion of reconstructed embryos could implant after their transfer into the oviducts of foster mothers (less than 5%), we show that at least some of them can develop into normal young. 相似文献
48.
Trévisiol E Renard A Defrancq E Lhomme J 《Nucleosides, nucleotides & nucleic acids》2000,19(9):1427-1439
We describe the reaction of oligonucleotides containing an aldehydic group at the 5'-end or inside the sequence with an oxyamino label. The reaction was found to be highly selective and represents an efficient method for derivatization of oligonucleotides. 相似文献
49.
50.
van Dijken JP Bauer J Brambilla L Duboc P Francois JM Gancedo C Giuseppin ML Heijnen JJ Hoare M Lange HC Madden EA Niederberger P Nielsen J Parrou JL Petit T Porro D Reuss M van Riel N Rizzi M Steensma HY Verrips CT Vindeløv J Pronk JT 《Enzyme and microbial technology》2000,26(9-10):706-714
To select a Saccharomyces cerevisiae reference strain amenable to experimental techniques used in (molecular) genetic, physiological and biochemical engineering research, a variety of properties were studied in four diploid, prototrophic laboratory strains. The following parameters were investigated: 1) maximum specific growth rate in shake-flask cultures; 2) biomass yields on glucose during growth on defined media in batch cultures and steady-state chemostat cultures under controlled conditions with respect to pH and dissolved oxygen concentration; 3) the critical specific growth rate above which aerobic fermentation becomes apparent in glucose-limited accelerostat cultures; 4) sporulation and mating efficiency; and 5) transformation efficiency via the lithium-acetate, bicine, and electroporation methods. On the basis of physiological as well as genetic properties, strains from the CEN.PK family were selected as a platform for cell-factory research on the stoichiometry and kinetics of growth and product formation. 相似文献