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981.
The synthesis of a new fluorescent cholesterol analog is described. The analog contains a cholesterol nucleus attached via a hydrophilic spacer to N-4-nitrobenzo-2-oxa-1,3-diazole. Since the cholesterol moiety is not perturbed this molecule probably interacts with lipid bilayers in much the same way as cholesterol itself does. The compound can be readily incorporated into small unilamellar vesicles by sonicating a mixture of it with egg yolk phosphatidylcholine in a buffer. Furthermore, the analog can be incorporated into preformed membranes either by exchange from vesicles containing the analog or by uptake from sonicated micelles of the analog. Thus this analog shows potential as a useful tool for studying the interactions of cholesterol with cell membranes. 相似文献
982.
The synthesis of storage proteins in trees of poplar (Populus x canadensis Moench) could not only be induced by a shift from long-day to short-day conditions but also by either a low-temperature treatment or by nitrogen feeding under continuous long-day conditions. The synthesis of the protein did not depend on the cessation of growth and the formation of a terminal bud. The accumulation of the storage protein was in all cases preceded by a drastic increase in the level of the corresponding mRNA.Abbreviations cDNA
copy DNA
- kDA
kilodalton 相似文献
983.
The present work describes the genetic modification of a hybridoma cell line with the aim to change its metabolic behaviour,
particularly reducing the amounts of ammonia and lactate produced by the cells. The cellular excretion of ammonia was eliminated
by transfection of a cloned glutamine synthetase gene. The metabolic characterisation of the transformed cell line includes
the analysis of the changes introduced in its intracellular metabolic fluxes by means of a stoichiometric model. Furthermore,
the reduction of lactate accumulation was attempted through an antisense mRNA approach, aiming to generate a rate limiting
step in the glycolytic pathway, thus lowering the glucose consumption rate. The physiological results obtained with the transformed
cells are discussed. A maximum reduction of about 47% in the glucose consumption rate was obtained for one of the transformations.
However a main drawback was the lack of stability of the transformed cells
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
984.
985.
986.
987.
Abstract: We identified GABAA receptor subunits in rat retina using PCR. The high degree of conservation among previously described members of ligand-gated anion channels in transmembrane domains was used to design degenerate sense and antisense oligonucleotides. These oligonucleotides were used as primers for PCR, which was applied to the rat retina cDNA. Analysis of clones derived from the PCR amplification identified the GABAAα1, β1, β3, and γ2 subunits and the glycine α1 subunit. In addition, two clones closely related to the human GABAAρ-subunit class were obtained. Molecular cloning revealed one of them as the rat counterpart of the human ρ2 subunit. Northern blot analysis demonstrated the expression of mRNAs for ρ subunits in retina. These results further support the hypothesis that bicuculline-insensitive GABA channels in rat retina are comprised of ρ subunits. 相似文献
988.
Xin Zhao Dong-Yang Tang Xu Zuo Tian-Dong Zhang Cheng Wang 《Journal of cellular physiology》2019,234(11):19886-19894
To construct a long noncoding RNA (lncRNA)–microRNA (miRNA)–messenger RNA (mRNA) regulatory network related to epithelial ovarian cancer (EOC) cisplatin-resistant, differentially expressed genes (DEGs), differentially expressed lncRNAs (DELs), and differentially expressed miRNAs (DEMs) between MDAH and TOV-112D cells lines were identified. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were conducted to analyze the biological functions of DEGs. Downstream mRNAs or upstream lncRNAs for miRNAs were analyzed at miRTarBase 7.0 or DIANA-LncBase V2, respectively. A total of 485 significant DEGs, 85 DELs, and 5 DEMs were identified. Protein–protein interaction (PPI) network of DEGs contrains 81 nodes and 141 edges was constructed, and 25 hub genes related to EOC cisplatin-resistant were identified. Subsequently, a lncRNA–miRNA–mRNA regulatory network contains 4 lncRNAs, 4 miRNAs, and 35 mRNAs was established. Taken together, our study provided evidence concerning the alteration genes involved in EOC cisplatin-resistant, which will help to unravel the mechanisms underlying drug resistant. 相似文献
989.
Jian Jun Duan Ronald J. Prokopy Chih-Ming Yin Chris Bergweiler H. Oouchi 《Entomologia Experimentalis et Applicata》1995,77(1):17-21
Three-day old female apple maggot flies,Rhagoletis pomonella (Walsh), were topically exposed to different doses (0.1, 1, 10, and 100 μg per fly) of a juvenile hormone mimic, pyriproxyfen,
in the laboratory. Pyriproxyfen had little lethal effect on females except at the extremely high dose of 100 μg. It also had
no significant effect on egg viability of treated females. A non-lethal dose of 1 μg per fly did, however, enhance significantly
the fecundity (egg production) as well as the ovarian development (number of eggs in ovaries and length of egg folicles) of
treated flies. We conclude that pyriproxyfen could be a useful aid in exploring endocrine regulation of feeding and reproductive
physiology behavior inR. pomonella, about which current knowledge is scant. 相似文献
990.