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151.
H. de Verneuil B. Grandchamp Chantal Foubert Dominique Weil Cong Van N'Guyen Marie-Sylvie Gross Shigeru Sassa Y. Nordmann 《Human genetics》1984,66(2-3):202-205
Summary A specific enzyme immunoassay of uroporphyrinogen decarboxylase was developed and applied to the detection of the human enzyme in man-rodent somatic cell hybrids. This method allowed to assign the gene for uroporphyrinogen decarboxylase to human chromosome 1. 相似文献
152.
C. Julier D. Weil P. Couillin J. C. Côté Cong Van Nguyen C. Foubert A. Boué J. P. Thirion J. C. Kaplan C. Junien 《Human genetics》1984,67(2):174-177
Summary We used a cloned human cDNA probe homologous to the placenta chorionic gonadotropin subunit (CGB) and to the pituitary luteinizing hormone subunit (LHB) and Southern blotting techniques to analyse DNA from a series of rodent x human somatic cell hybrids for the presence of specific gonadotropin subunit related sequences. Our results provide evidence for the assignment and linkage of the eight genes (or pseudogenes) coding for the subunit of these glycoprotein hormones to chromosome 19. Moreover, we observed a strict concordance between the permissivity of mouse x man hybrid cells to enteroviruses (which is linked to the presence of specific cell receptors encoded by human chromosome 19) and the presence of CGB and LHB related sequences, thus confirming the localization of the structural genes for the subunits on chromosome 19.This work was supported in part by INSERM grants CRL 81 1041 and by MRC grant MT 4860 相似文献
153.
154.
Fischer-344 (F-344) rats differ from other common rat strains in that they
fail to show any preference for NaCl at any concentration in two- bottle
preference tests. Because 100 microM amiloride partially blocks the
NaCl-evoked chorda tympani (CT) response in electrophysiological studies,
we tested NaCl preference (0.068-0.273 M) in F-344 rats with and without
100 microM amiloride solution as the solvent. A third group was tested with
unadulterated NaCl solutions following CT transection. Amiloride had no
significant effect on the NaCl preference-aversion function, whereas CT
transection significantly reduced NaCl avoidance. These results suggest
that the amiloride-sensitive component of the NaCl response is not
necessary for F-344 rats to display avoidance of NaCl, but the entire CT
input is.
相似文献
155.
M. Kuntz S. Römer C. Suire P. Hugueney J.H. Weil R. Schantz B. Camara 《The Plant journal : for cell and molecular biology》1992,2(1):25-34
Geranylgeranyl pyrophosphate synthase is a key enzyme in plant terpenoid biosynthesis. Using specific antibodies, a cDNA encoding geranylgeranyl pyrophosphate synthase has been isolated from bell pepper (Capsicum annuum) ripening fruit. The cloned cDNA codes for a high molecular weight precursor of 369 amino acids which contains a transit peptide of approximately 60 amino acids. In-situ immunolocalization experiments have demonstrated that geranylgeranyl pyrophosphate synthase is located exclusively in the plastids. Expression of the cloned cDNA in E. coli has unambiguously demonstrated that the encoded polypeptide catalyzes the synthesis of geranylgeranyl pyrophosphate by the addition of isopentenyl pyrophosphate to an allylic pyrophosphate. Peptide sequence comparisons revealed significant similarity between the sequences of the C. annuum geranylgeranyl pyrophosphate synthase and those deduced from carotenoid biosynthesis (crtE) genes from photosynthetic and non-photosynthetic bacteria. In addition, four highly conserved regions, which are found in various prenyltransferases, were identified. Furthermore, evidence is provided suggesting that conserved and exposed carboxylates are directly involved in the catalytic mechanism. Finally, the expression of the geranylgeranyl pyrophosphate synthase gene is demonstrated to be strongly induced during the chloroplast to chromoplast transition which occurs in ripening fruits, and is correlated with an increase in enzyme activity. 相似文献
156.
Aliakbar Dehno Khalaji Matthias Weil Marzieh Daryanavard 《Inorganica chimica acta》2009,362(13):4837-4842
The reaction of the bidentate Schiff-base ligands (3,4,5-MeO-ba)2en (L1) and (4-Me-ba)2en (L2) with Cu(SCN) in CH3CN yielded two copper(I) coordination polymers [Cu(L1)(SCN)]n (1) and [Cu(L2)(SCN)]n (2), which have been characterized by elemental analyses, IR- and 1H NMR-spectroscopy, and X-ray crystallography. The non-centrosymmetric structures of both Cu(I) complexes consist of an one-dimensional polymeric chain in which copper(I) ions are bridged by two thiocyanate groups bonding in an end-to-end fashion. The Cu(I)?Cu(I) separation is 5.604 Å in 1 and 5.706 Å in 2. 相似文献
157.
Interest in the use of low-copy nuclear genes for phylogenetic analyses of
plants has grown rapidly, because highly repetitive genes such as those
commonly used are limited in number. Furthermore, because low- copy genes
are subject to different evolutionary processes than are plastid genes or
highly repetitive nuclear markers, they provide a valuable source of
independent phylogenetic evidence. The gene for granule-bound starch
synthase (GBSSI or waxy) exists in a single copy in nearly all plants
examined so far. Our study of GBSSI had three parts: (1) Amino acid
sequences were compared across a broad taxonomic range, including grasses,
four dicotyledons, and the microbial homologs of GBSSI. Inferred structural
information was used to aid in the alignment of these very divergent
sequences. The informed alignments highlight amino acids that are conserved
across all sequences, and demonstrate that structural motifs can be highly
conserved in spite of marked divergence in amino acid sequence. (2)
Maximum-likelihood (ML) analyses were used to examine exon sequence
evolution throughout grasses. Differences in probabilities among
substitution types and marked among-site rate variation contributed to the
observed pattern of variation. Of the parameters examined in our set of
likelihood models, the inclusion of among-site rate variation following a
gamma distribution caused the greatest improvement in likelihood score. (3)
We performed cladistic parsimony analyses of GBSSI sequences throughout
grasses, within tribes, and within genera to examine the phylogenetic
utility of the gene. Introns provide useful information among very closely
related species, but quickly become difficult to align among more divergent
taxa. Exons are variable enough to provide extensive resolution within the
family, but with low bootstrap support. The combined results of amino acid
sequence comparisons, maximum-likelihood analyses, and phylogenetic studies
underscore factors that might affect phylogenetic reconstruction. In this
case, accommodation of the variable rate of evolution among sites might be
the first step in maximizing the phylogenetic utility of GBSSI.
相似文献
158.
Eight small subunits of Euglena ribulose 1-5 bisphosphate carboxylase/oxygenase are translated from a large mRNA as a polyprotein. 总被引:7,自引:1,他引:7 下载免费PDF全文
The small subunit (SSU) of ribulose 1-5 bisphosphate carboxylase/oxygenase is a 15 kd protein in Euglena gracilis. The protein is synthesized as a 130 kd precursor as shown by immunoprecipitation of in vitro translation products and confirmed by immunoprecipitation of in vivo pulse-labeled Euglena proteins. From the published SSU amino acid sequence, an oligonucleotide was synthesized that specifically hybridizes to a large mRNA whose length (approximately 4.3 kb) is consistent with the precursor size. The complete nucleotide sequence of the SSU mRNA was obtained by sequencing a cDNA clone from a lambda gt11 library and completed by direct mRNA sequencing. We report for the first time the complete sequence of a large mRNA and show that it encodes eight consecutive SSU mature molecules. The deduced precursor amino acid sequence shows that the amino terminus of the first SSU molecule is preceded by a 134 amino acid peptide which is cleaved during the maturation process. This long transit peptide exhibits features characteristic of signal peptides involved in the secretion of proteins through the endoplasmic reticulum. This is in agreement with the idea that the third (outer) membrane of the Euglena chloroplast envelope is of endoplasmic reticulum origin. 相似文献
159.
D A Compton M M Weil L Bonetta A Huang C Jones H Yeger B R Williams L C Strong G F Saunders 《Genomics》1990,6(2):309-315
In a previous report, we described a contiguous restriction map of chromosome band 11p13 that localized the Wilms tumor locus to a small group of NotI fragments. In an effort to identify and isolate the 11p13-associated sporadic Wilms tumor locus, we developed a panel of NotI fragment-specific DNA probes. These probes were selected from genomic libraries constructed using the Chinese hamster ovary-human somatic cell hybrid carrying only human 11p. The libraries were prepared from NotI-digested DNA after size selection by pulsed-field gel electrophoresis. The selected NotI fragments had been previously targeted on the basis of deletion mapping as having a high probability of containing the Wilms tumor locus. We used these newly identified 11p13-specific probes to improve the resolution of the restriction map spanning the Wilms tumor locus. The locus has been defined by a homozygous deletion in a sporadic Wilms tumor. Using these probes, the region of homozygous deletion in this tumor and presumably all or part of the Wilms tumor gene have been confined to two small SfiI fragments spanning less than 350 kb. 相似文献
160.