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1.
Sébastien Derégnaucourt & Jean-Charles Guyomarc'h 《Ethology : formerly Zeitschrift fur Tierpsychologie》2003,109(2):107-119
Each year, thousands of domestic Japanese and hybrid quails are released within the breeding range of the European quail. We showed recently that no post‐zygotic isolating mechanisms have yet been established between these subspecies. The aim of this study was to investigate whether pre‐zygotic mechanisms are strong enough to prevent hybridization. We tested the level of subspecies selectivity in females of European and Japanese quail respectively using playbacks of European, hybrid and Japanese male mating calls. European quail females emitted the greatest number of rally calls in response to mating calls by conspecific males. Their responses were the weakest to mating calls produced by males of the other subspecies and intermediate to mating calls by hybrid males. In contrast, Japanese quails produced similar responses to all types of mating calls. These results suggest that mixed pairs could form in the wild. The European quail could thus become one of the most endangered galliforms of the Western Palearctic. 相似文献
2.
Boneca IG de Reuse H Epinat JC Pupin M Labigne A Moszer I 《Nucleic acids research》2003,31(6):1704-1714
Huge amounts of genomic information are currently being generated. Therefore, biologists require structured, exhaustive and comparative databases. The PyloriGene database (http://genolist.pasteur.fr/PyloriGene) was developed to respond to these needs, by integrating and connecting the information generated during the sequencing of two distinct strains of Helicobacter pylori. This led to the need for a general annotation consensus, as the physical and functional annotations of the two strains differed significantly in some cases. A revised functional classification system was created to accommodate the existing data and to make it possible to classify coding sequences (CDS) into several functional categories to harmonize CDS classification. The annotation of the two complete genomes was revised in the light of new data, allowing us to reduce the percentage of hypothetical proteins from approximately 40 to 33%. This resulted in the reassignment of functions for 108 CDS (approximately 7% of all CDS). Interestingly, the functions of only approximately 13% of CDS (222 out of 1658 CDS) were annotated as a result of work done directly on H.pylori genes. Finally, comparison of the two published genomes revealed a significant amount of size variation between corresponding (orthologous) CDS. Most of these size variations were due to natural polymorphisms, although other sources of variation were identified, such as pseudogenes, new genes potentially regulated by slipped-strand mispairing mechanism, or frame-shifts. 113 of these differences were due to different start codon assignments, a common problem when constructing physical annotations. 相似文献
3.
Omega-piperidinoalkanamine derivatives with fluorescent moieties (2-cyanoisoindol-1-yl, 7-nitrobenzofurazan-4-yl) have been synthesized starting from piperidine in three steps. The compounds display moderate to good histamine hH(3) receptor affinities with K(i) values ranging from 178 to 11nM. The new compounds may act as tools for identification and understanding of the binding site on the histamine H(3) receptor. 相似文献
4.
5.
Jean-Charles Cadoret Raphaël Demoulière Johann Lavaud Jean Houmard Anne-Lise Etienne 《BBA》2004,1659(1):100-104
The chlorophyll-protein CP43′ (isiA gene) induced by stress conditions in cyanobacteria is shown to serve as an antenna for Photosystem II (PSII), in addition to its known role as an antenna for Photosystem I (PSI). At high light intensity, this antenna is converted to an efficient trap for chlorophyll excitations that protects system II from photo-inhibition. In contrast to the ‘energy-dependent non-photochemical quenching’ (NPQ) in chloroplasts, this photoprotective energy dissipation in cyanobacteria is triggered by blue light. The induction is proportional to light intensity. Induction and decay of the quenching exhibit the same large temperature-dependence. 相似文献
6.
Intraperitoneal administration of the mycotoxin penitrem A 30 min before a training session in passive avoidance task, impaired
performance of rats subjected to a test-session 24 h after. This effect was not antagonised by pretraining administration
of physostigmine or bicuculline. Administration of penitrem A 20 min before a training session or 30 min before a test-session
did not impair performance. In the Morris water maze, doses of penitrem A that induces slight to moderate tremors, but not
a lower dose, disrupted place learning. These results suggest that penitrem A disrupts the processes that take place at the
time of acquisition, but not those just after acquisition, and does not alter the restitution of information. This effect
would not be related to a decrease of cholinergic neurotransmission nor to a stimulation of GABA A receptors. Nevertheless,
it could not be totally excluded that the performance impairments induced by penitrem A would be secondary to a motor disruption.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
7.
Nathalie Griffon Catherine Pilon François Sautel Jean-Charles Schwartz Pierre Sokoloff 《Journal of neurochemistry》1997,68(1):1-9
Abstract: As cerebral neurons express the dopamine D1 receptor positively coupled with adenylyl cyclase, together with the D3 receptor, we have investigated in a heterologous cell expression system the relationships of cyclic AMP with D3 receptor signaling pathways. In NG108-15 cells transfected with the human D3 receptor cDNA, dopamine, quinpirole, and other dopamine receptor agonists inhibited cyclic AMP accumulation induced by forskolin. Quinpirole also increased mitogenesis, assessed by measuring [3 H]thymidine incorporation. This effect was blocked partially by genistein, a tyrosine kinase inhibitor. Forskolin enhanced by 50–75% the quinpirole-induced [3 H]thymidine incorporation. This effect was maximal with 100 n M forskolin, occurred after 6–16 h, was reproduced by cyclic AMP-permeable analogues, and was blocked by a protein kinase A inhibitor. Forskolin increased D3 receptor expression up to 135%, but only after 16 h and at concentrations of >1 µ M . Thus, in this cell line, the D3 receptor uses two distinct signaling pathways: it efficiently inhibits adenylyl cyclase and induces mitogenesis, an effect possibly involving tyrosine phosphorylation. Activation of the cyclic AMP cascade potentiates the D3 receptor-mediated mitogenic response, through phosphorylation by a cyclic AMP-dependent kinase of a yet unidentified component. Hence, transduction of the D3 receptor can involve both opposite and synergistic interactions with cyclic AMP. 相似文献
8.
Abstract: Substrate utilization of microbial cells extracted from soil with a 0.85% aqueous sodium chloride solution, was determined to estimate effects on soil microorganisms at the community level with microtiter plates (Biolog GN®) containing 95 different sources of organic carbon. A consistent pattern of utilized substrates was obtained after 24 h of microtiter plate incubation at 28°C. The absorbance values (OD590 ) obtained from a microtiter plate reader after background correction were transformed by using the average absorbance values of oxidized substrates as a threshold to distinguish between well utilized and poorly or non-utilized substrates and thereby reduce variances between replicates. Doubling times of the extracted soil microorganisms in the microtiter plates were tested with 12 substrates and ranged from 1.96 h to 3.23 h, depending on the carbon source. The carbon source utilization assay was used to assess the effects of soil inoculation with Corynebacterium glutamicum with and without a genetically engineered plasmid (pUN1; 6.3 kb), which encoded for the synthesis of the mammalian protease inhibiting peptide, aprotinin. Additionally, aprotinin itself was added at two concentrations to soil samples. An identical decrease in the number of carbon sources utilized, especially carbohydrates, occurred upon soil inoculation with both C. glutamicum strains after inoculation with 106 cells g−1 soil. This effect was only detectable during the first three weeks of incubation, as long as cell numbers of C. glutamicum (pUN1) were above 105 cfu g−1 . Soil amendment with aprotinin resulted in utilization of additional substrates, most of them carbohydrates. With 0.1 mg aprotinin g−1 soil this stimulation lasted 2 days and with 10 mg g−1 it lasted for 7 days. 相似文献
9.
Several lines of evidence indicate that the i.v. injection of 3H-pimozide results in a specific in vivo binding of the neuroleptic to dopaminergic receptors.First, 3H-pimozide is preferentially accumulated in the striatum as compared to non-dopaminergic structures like the cerebellum. Second, the selective accumulation of 3H-pimozide is prevented by prior administration of various neuroleptics as well as by apomorphine. Moreover, doses of antagonists which prevent this accumulation were identical to those which lead to an increased striatal HVA level. Third, 3H-pimozide accumulation is not modified by the administration of a variety of non-dopaminergic agents.However, 3H-pimozide binding is not prevented either by indirect dopamine agonists and is even greatly increased by d-amphetamine at high doses. The possibility that direct or indirect dopamine agonists may favour the binding of the antagonist through a modification of receptor sites is discussed. 相似文献
10.
Jean-Charles Gabillard Cécile Rallière Nathalie Sabin Pierre-Yves Rescan 《BMC biotechnology》2010,10(1):39