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141.
Mark P. Foster Deborah S. Wuttke Karen R. Clemens Wolfgang Jahnke Ishwar Radhakrishnan Linda Tennant Martine Reymond John Chung Peter E. Wright 《Journal of biomolecular NMR》1998,12(1):51-71
We report the NMR resonance assignments for a macromolecular protein/DNA complex containing the three amino-terminal zinc fingers (92 amino acid residues) of Xenopus laevis TFIIIA (termed zf1-3) bound to the physiological DNA target (15 base pairs), and for the free DNA. Comparisons are made of the chemical shifts of protein backbone1 HN, 15N,13 C and13 C and DNA base and sugar protons of the free and bound species. Chemical shift changes are analyzed in the context of the structures of the zf1-3/DNA complex to assess the utility of chemical shift change as a probe of molecular interfaces. Chemical shift perturbations that occur upon binding in the zf1-3/DNA complex do not correspond directly to the structural interface, but rather arise from a number of direct and indirect structural and dynamic effects. 相似文献
142.
Martine Arpagaus Didier Combes Emmanuel Culetto Marta Grauso Yann Fedon Rita Romani Jean-Pierre Toutant 《Journal of Physiology》1998,92(5-6)
Whereas a single gene encodes acetylcholinesterase (AChE) in vertebrates and most insect species, four distinct genes have been cloned and characterized in the nematode Caenorhabditis elegans. We found that ace-1 (mapped to chromosome X) is prominently expressed in muscle cells whereas ace-2 (located on chromosome I) is mainly expressed in neurons. Ace-x and ace-y genes are located in close proximity on chromosome II where they are separated by only a few hundred base pairs. The role of these two genes is still unknown.
Résumé
À l'inverse de la situation des vertébrés et de la majorité des insectes, chez qui un gène unique code pour l'acétylcholinestérase (AChE), quatre gènes d'AChE ont été clones et caractérisés chez Caenorhabditis elegans. Le gène ace-1 (localisé sur le chromosome X) et le gène ace-2 (chromosome I) assurent respectivement l'expression de l'AChE dans les tissus musculaire (ace-1) et nerveux (ace-2). Les gènes ace-x et ace-y ne sont séparés que de quelques centaines de paires de bases sur le chromosome II et leur rôle est pour l'instant inconnu. 相似文献143.
Dominique Delforge Barbara Gillon Muriel Art Janique Dewelle Martine Raes José Remacle 《Letters in Peptide Science》1998,5(2-3):87-91
A synthetic adhesion protein was designed by chemical grafting of the RGD tailed cyclic peptide cyclo[-d-Val-Arg-Gly-Asp-Glu(-Ahx-Tyr-Cys-NH2)-] on the carrier protein bovine serum albumin (BSA). The cyclic conformation of the RGD motif grafted on the protein mimics the conformation of the motif displayed in native adhesion proteins such as fibronectin. The adhesion of the cells on polystyrene coated with the conjugate BSA–peptide was similar or even better than the one obtained when the proadhesive protein fibronectin was coated on the plates. Results also indicated that covalent coupling of the peptide on BSA is not absolutely required, since simple adsorption of the peptide on the protein coated on plates was efficient for enhancing cell adhesion. These results show that polystyrene support can be reconditioned with conformationally constrained RGD peptides to enhance cell adhesion on solid supports. The same methodology can be adapted for the development of new biomaterials based on the recognition of specific peptides. 相似文献
144.
145.
Franck-Duchenne Martine Wang Yuwen Ben Tahar Sofia Beachy Roger N. 《Plant Cell, Tissue and Organ Culture》1998,53(2):79-84
In vitro regeneration of sweet pepper (Capsicum annuum L. cvs Jupiter and Pimiento Perfection) has been performed via direct
organogenesis. The resulting shoot-buds were placed on media containing 24-epi-brassinolide (EBR) 0.1 μM, a plant steroid
lactone, in the presence or absence of zeatin 9.1 μM plus GA3 5.2 μM for further stem elongation. Different responses to these
treatments were recorded depending upon the protocols used and the genotypes tested. It appears that EBR does not always act
directly on stem elongation but may be an elicitor and/or an enhancer of elongation in concert with endogenous and other exogenously
added growth regulators. Elongated shoots were easily rooted with alpha-naphtalenacetic acid 0.5 μM (0.1 mgl-1) and transfered
to soil, and following acclimation were taken to maturity in the greenhouse.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
146.
Elizabeth Faris Crowell Martine GonneauSamantha Vernhettes Herman Höfte 《Comptes rendus biologies》2010,333(4):320-324
Plant growth and development depend on anisotropic cell expansion. Cell wall yielding provides the driving force for cell expansion, and is regulated in part by the oriented deposition of cellulose microfibrils around the cell. Our current understanding of anisotropic cell expansion combines hypotheses generated by more than 50 years of research. Here, we discuss the evolving views of researchers in the field of cellulose synthesis, and highlight several unresolved questions. Recent results using live-cell imaging have illustrated novel roles for cortical microtubules in cellulose synthesis, and further research using these approaches promises to reveal exciting links between the cytoskeleton, intracellular trafficking, and anisotropic growth. 相似文献
147.
148.
Neïla Hamza Frédéric Silvestre Mohamed Mhetli Ines Ben Khemis Marc Dieu Martine Raes Chantal Cahu Patrick Kestemont 《Comparative biochemistry and physiology. Part D, Genomics & proteomics》2010,5(2):130-137
A comparative proteomic approach was used to assess the protein expression profile in the liver of 34 days old pikeperch larvae fed from day 10 post hatching, with three isoproteic and isolipidic formulated diets varying by their phospholipid (PL) contents (% dry diet weight): 1.4% (PL1), 4.7% (PL5) and 9.5% (PL9). Using 2D-DIGE minimal labelling of liver extracts, we were able to show 56 protein spots with a differential intensity (p < 0.05) depending on the dietary PL content. Among these spots, 11 proteins were unambiguously identified using nanoLC-MS/MS tandem mass spectrometry. In the PL9 larvae, our results indicate that the glycolytic pathway could be down-regulated due to the under-expression of the fructose biphosphate aldolase B and the phosphoglucomutase 1. Meanwhile, propionyl coenzyme A carboxylase (a gluconeogenic enzyme) was under-expressed. In addition, another gluconeogenic and lipogenic enzyme, pyruvate carboxylase, was identified in 3 different spots as being under-expressed in fish fed with the intermediate PL level (PL5). A high PL content increased the expression of sarcosine dehydrogenase, an enzyme involved in methionine metabolism, along with vinculin, a structural protein. Moreover, several stress proteins (glutathione S-transferase M, glucose regulated protein 75 and peroxiredoxin-1) were modulated in response to the dietary PL level and fatty acid composition. In the larvae fed with the lowest dietary PL content (PL1), over-expression of both GSTM and GRP75 might indicate a cellular stress in this experimental treatment, while the under-expression of Prx1 might indicate a lower defence against oxidative stress. In conclusion, this nutriproteomic approach showed significant modifications of protein expression in the liver of pikeperch larvae fed different PL contents, highlighting the importance of these nutrients and their influence on metabolism processes and on stress response. 相似文献
149.
Kyle K Biggar Cheng-Wei Wu Shannon N Tessier Jing Zhang Fabien Pifferi Martine Perret Kenneth B Storey 《基因组蛋白质组与生物信息学报(英文版)》2015,13(2):81-90
Very few selected species of primates are known to be capable of entering torpor. This exciting discovery means that the ability to enter a natural state of dormancy is an ancestral trait among primate... 相似文献
150.
Shannon N Tessier Jing Zhang Kyle K Biggar Cheng-Wei Wu Fabien Pifferi Martine Perret f Kenneth B Storey 《基因组蛋白质组与生物信息学报(英文版)》2015,13(2):91-102
Gray mouse lemurs (Microcebus murinus) from Madagascar present an excellent model for studies of torpor regulation in a primate species. In the present study, we analyzed the response of the insulin si... 相似文献