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31.
Yves Paquette Yannick Merlen Brigitte Malette Gilles Bleau 《Molecular reproduction and development》1995,42(4):388-396
Oviductins are high-molecular-weight glycoproteins specifically secreted by the oviduct. These proteins bind to the zona pellucida of the ovulated oocyte and remain associated with the embryo during its transit in the oviduct. They may be involved in fertilization and early embryonic development. In order to explore their putative biological function, the cDNA sequence corresponding to oviductin in the golden hamster was determined. We found that the deduced amino acid sequence of this heavily O-glycosylated protein presents characteristics typical of mucins, including serine- or threonine-rich tandem repeats. Analysis of several cDNA clones and of genomic DNA revealed the presence of a single copy gene with two frequent alleles differing in the number of repeats. Comparison with oviductin sequences from other mammals indicates a high degree of conservation amongst species, except for the repeat region which shows divergence, notably in the number of repeats. Based on its biochemical and genetic properties, hamster oviductin can now be classified as a secretory mucin. This concept provides a new insight in the elucidation of its biological role: oviductin could possibly provide the oviduct and the oocyte with a protective coating ensuring normal tubal function and embryonic development. © 1995 wiley-Liss, Inc. 相似文献
32.
Josiane Girardie Adrien Girardie Alain Van Dorsselaer Odile Sorokine Serge Geoffre Michel Hospital Gilles Precigoux 《Journal of peptide science》1995,1(5):311-318
An original insect neurohormone of 65 residues was synthesized by the solid-phase methodology using t-Boc strategy and Boc-Val-PAM–resin. The purification, conducted by several steps of liquid chromatography having mass, polarity or charge as separative criteria, yielded the product with the correct molecular weight of 6922 Da determined by mass spectrometry. The synthetic peptide had both the same affinity for the antinative neurohormone serum and the same biological activity as the native neurohormone. 相似文献
33.
Iciar Martinez Bent Dreyer Aasta Agersborg Annick Leroux Gilles Boeuf 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》1995,112(4)
Rearing of 1-year-old Arctic charr (Salvelinus alpinus) at 12°C, as well as the administration of 50 or 75 mgT3/kg feed, accelerated the neonatal to adult fast myosin heavy chain transition, but the effect of temperature was more dramatic than the effect of T3 administration. The endogenous plasma levels of T3 in charrs reared at 12°C were higher than those of analogous groups reared at natural temperature, which in the period under study was between 0.5 and 12°C. As in other species, T3 seemed to play a role in the regulation of the neonatal to adult fast myosin isoform transition by down-regulating the levels of the neonatal and increasing the levels of an adult fast myosin heavy chain. Temperature seemed to accelerate this transition at least, but not only, by inducing an increase in the endogenous levels of T3 in the Arctic charr. 相似文献
34.
Use of Genetic and Physical Mapping to Locate the Spinal Muscular Atrophy Locus between Two New Highly Polymorphic DNA Markers 总被引:9,自引:2,他引:7 下载免费PDF全文
Olivier Clermont Philippe Burlet Lydie Burglen Suzie Lefebvre Fabrice Pascal John McPherson John J. Wasmuth Daniel Cohen Denis Le Paslier Jean Weissenbach Mark Lathrop Arnold Munnich Judith Melki 《American journal of human genetics》1994,54(4):687-694
The gene for autosomal recessive forms of spinal muscular atrophy (SMA) has recently been mapped to chromosome 5ql3, within a 4-cM region between the blocks D5S465/D5S125 and MAP-1B/D5S112. We identified two new highly polymorphic microsatellite DNA markers—namely, AFM265wf5 (D5S629) and AFM281yh9 (D5S637)—which are the closest markers to the SMA locus. Multilocus analysis by the location-score method was used to establish the best estimate of the SMA gene location. Our data suggest that the most likely location for SMA is between locus D5S629 and the block D5S637/D5S351/MAP-1B/D5S112/D5S357. Genetic analysis of inbred SMA families, based on homozygosity by descent and physical mapping using mega-YACs, gave additional information for the loci order as follows: cen–D5S6–D5S125/D5S465–D5S435–D5S629–SMA–D5S637–D5S351–MAP–1B/D5S112–D5S357–D5S39–tel. These data give the direction for bidirectional walking in order to clone this interval and isolate the SMA gene. 相似文献
35.
Chaubron Franck; Robert Fabien; Gendraud Michel; Petel Gilles 《Plant & cell physiology》1994,35(8):1179-1184
Plasmalemma ATPase from Jerusalem artichoke tubers was studiedin relation to the dormancy of tubers. After partial purification,one peptide of 110 kDa appeared on SDS PAGE electrophoresisfrom dormant and non-dormant materials. ATPase specific activitywas twice higher on dormant material in the crude and solubilizedfractions, but was the same in both materials after partialpurification. Immunolabeling of this enzyme was made using aspecific antibody raised against the C terminal portion of theH+-ATPase from Arabidopsis thaliana. Immunolabeling was morepronounced in dormant material, in vitro and in situ. Severalworks had shown that the C terminal part of the enzyme couldbe involved in its regulation. The results presented are discussedin relation to the hypothesis according to which an internaleffector could modulated the plasmalemma ATPase activity, duringdormancy breaking. (Received October 25, 1993; Accepted September 6, 1994) 相似文献
36.
Jamal Mouslim Lucien David Gilles Pétel Michel Gendraud 《Applied microbiology and biotechnology》1993,39(4-5):585-588
Addition of methyl oleate to a Streptomyces hygroscopicus NRRL B-1865 culture modified the metabolic properties of this strain. This addition decreased the pH of the medium, increased the valine uptake of the cells and reduced their consumption of glucose until the beginning of antibiotic biosynthesis, which was delayed. At the same time, an increase in growth (× 1.8) and a marked improvement in antibiotic production (× 20) could be observed. The use of labelled methyl oleate showed that methyl oleate was not a precursor of antibiotics produced by S. hygroscopicus NRRL B-1865. It is suggested that methyl oleate addition may cause some alteration in membrane permeability, inducing an increase in H+ extrusion and stimulating the accumulation of branched amino acids, known to be direct precursors of polyether antibiotics.
Correspondence to: L. David 相似文献
37.
Michel J. Gauthier Gilles N. Flatau René L. Clément Patrick M. Munro 《Microbial ecology》1993,26(1):29-35
Using strains with or without the PhoE porin or different components of the phosphate regulon, we determined that maintenance of the culturability of Escherichia coli in seawater depended significantly on the presence of structures allowing access of phosphate ions to the periplasm, then to the cytoplasm of cells. Cells totally deprived of the two main phosphate transport systems (Pit, Pst) exhibited the highest loss of culturability. Most of this effect resulted from the loss of the high-affinity Pst system, and more specifically that of the periplasmic phosphate-binding protein PhoS. Survival was enhanced in seawater supplemented with phosphate (0.5 mm), whether or not these structures were present. From an ecological point of view, it is assumed that the presence of phosphate ions, even at low concentrations, can influence the behavior of E. coli cells in seawater.
Offprint requests to: M.J. Gauthier 相似文献
38.
Paolina Garbeva Mariana Avalos Dana Ulanova Gilles P. van Wezel Jeroen S. Dickschat 《Environmental microbiology》2023,25(9):1565-1574
Geosmin may be the most familiar volatile compound, as it lends the earthy smell to soil. The compound is a member of the largest family of natural products, the terpenoids. The broad distribution of geosmin among bacteria in both terrestrial and aquatic environments suggests that this compound has an important ecological function, for example, as a signal (attractant or repellent) or as a protective specialized metabolite against biotic and abiotic stresses. While geosmin is part of our everyday life, scientists still do not understand the exact biological function of this omnipresent natural product. This minireview summarizes the current general observations regarding geosmin in prokaryotes and introduces new insights into its biosynthesis and regulation, as well as its biological roles in terrestrial and aquatic environments. 相似文献
39.
Niraj Shrestha Pallavi Chaturvedi Xiaoyun Zhu Michael J. Dee Varghese George Christopher Janney Jack O. Egan Bai Liu Mark Foster Lynne Marsala Pamela Wong Celia C. Cubitt Jennifer A. Foltz Jennifer Tran Timothy Schappe Karin Hsiao Gilles M. Leclerc Lijing You Christian Echeverri Catherine Spanoudis Ana Carvalho Leah Kanakaraj Crystal Gilkes Nicole Encalada Lin Kong Meng Wang Byron Fang Zheng Wang Jin-an Jiao Gabriela J. Muniz Emily K. Jeng Nicole Valdivieso Liying Li Richard Deth Melissa M. Berrien-Elliott Todd A. Fehniger Peter R. Rhode Hing C. Wong 《Aging cell》2023,22(5):e13806
40.