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121.
122.
Manon JM van Oosten Radboud JEM Dolhain Jan W Koper Elisabeth FC van Rossum Marieke Emonts Khik H Han Jacques MGW Wouters Johanne MW Hazes Steven WJ Lamberts Richard A Feelders 《Arthritis research & therapy》2010,12(4):R159
Introduction
The glucocorticoid receptor (GR) plays an important regulatory role in the immune system. Four polymorphisms in the GR gene are associated with differences in glucocorticoid (GC) sensitivity; the minor alleles of the polymorphisms N363 S and BclI are associated with relative hypersensitivity to GCs, while those of the polymorphisms ER22/23EK and 9β are associated with relative GC resistance. Because differences in GC sensitivity may influence immune effector functions, we examined whether these polymorphisms are associated with the susceptibility to develop Rheumatoid Arthritis (RA) and RA disease severity. 相似文献123.
RNAs from all categories generate retrosequences that may be exapted as novel genes or regulatory elements 总被引:29,自引:0,他引:29
While the significance of middle repetitive elements had been neglected for a long time, there are again tendencies to ascribe most members of a given middle repetitive sequence family a functional role--as if the discussion of SINE (short interspersed repetitive elements) function only can occupy extreme positions. In this article, I argue that differences between the various classes of retrosequences concern mainly their copy numbers. Consequently, the function of SINEs should be viewed as pragmatic such as, for example, mRNA-derived retrosequences, without underestimating the impact of retroposition for generation of novel protein coding genes or parts thereof (exon shuffling by retroposition) and in particular of SINEs (and retroelements) in modulating genes and their expression. Rapid genomic change by accumulating retrosequences may even facilitate speciation [McDonald, J.F., 1995. Transposable elements: possible catalysts of organismic evolution. Trends Ecol. Evol. 10, 123-126.] In addition to providing mobile regulatory elements, small RNA-derived retrosequences including SINEs can, in analogy to mRNA-derived retrosequences, also give rise to novel small RNA genes. Perhaps not representative for all SINE/master gene relationships, we gained significant knowledge by studying the small neuronal non-messenger RNAs, namely BC1 RNA in rodents and BC200 RNA in primates. BC1 is the first identified master gene generating a subclass of ID repetitive elements, and BC200 is the only known Alu element (monomeric) that was exapted as a novel small RNA encoding gene. 相似文献
124.
125.
Sandro C Esteves Joan C Schertz Sidney Verza Jr Danielle T Schneider Silval FC Zabaglia 《Reproductive biology and endocrinology : RB&E》2009,7(1):111-11
Background
Over the last several decades, as a result of an evolution in manufacturing processes, a marked development has been made in the field of gonadotropins for ovarian stimulation. Initially, therapeutic gonadotropins were produced from a simple process of urine extraction and purification; now they are produced via a complex system involving recombinant technology, which yields gonadotropins with high levels of purity, quality, and consistency. 相似文献126.
Buller CL Heilig CW Brosius FC 《American journal of physiology. Renal physiology》2011,301(3):F588-F596
Enhanced GLUT1 expression in mesangial cells plays an important role in the development of diabetic nephropathy by stimulating signaling through several pathways resulting in increased glomerular matrix accumulation. Similarly, enhanced mammalian target of rapamycin (mTOR) activation has been implicated in mesangial matrix expansion and glomerular hypertrophy in diabetes. We sought to examine whether enhanced GLUT1 expression increased mTOR activity and, if so, to identify the mechanism. We found that levels of GLUT1 expression and mTOR activation, as evidenced by S6 kinase (S6K) and 4E-BP-1 phosphorylation, changed in tandem in cell lines exposed to elevated levels of extracellular glucose. We then showed that increased GLUT1 expression enhanced S6K phosphorylation by 1.7- to 2.9-fold in cultured mesangial cells and in glomeruli from GLUT1 transgenic mice. Treatment with the mTOR inhibitor, rapamycin, eliminated the GLUT1 effect on S6K phosphorylation. In cells lacking functional tuberous sclerosis complex (TSC) 2, GLUT1 effects on mTOR activity persisted, indicating that GLUT1 effects were not mediated by TSC. Similarly, AMP kinase activity was not altered by enhanced GLUT1 expression. Conversely, enhanced GLUT1 expression led to a 2.4-fold increase in binding of mTOR to its activator, Rheb, and a commensurate 2.1-fold decrease in binding of Rheb to glyceraldehyde 3-phosphate dehydrogenase (GAPDH) consistent with mediation of GLUT1 effects by a metabolic effect on GAPDH. Thus, GLUT1 expression appears to augment mesangial cell growth and matrix protein accumulation via effects on glycolysis and decreased GAPDH interaction with Rheb. 相似文献
127.
NA Rivers-Moore HF Dallas FC de Moor J Barendse 《African Journal of Aquatic Science》2018,43(3):215-227
Non-native vegetation in the riparian zone impacts on water temperatures, flow patterns, degree of shading, channel modification, and changes to natural sediment loads. Freshwater ecosystems in the Garden Route Initiative planning domain are of particular conservation value, because of the rich Gondwanaland relict aquatic macroinvertebrate fauna found in the rivers there, which are vulnerable to thermal changes. Data were collected during 2013 and 2014 at 19 sites on seven river systems between George and Knysna in the southern Cape, South Africa. These included 12 months of hourly water temperatures at all sites, and quantitative sampling of aquatic macroinvertebrates at ten sites. Each site was characterised in terms of water quality (pH, conductivity and turbidity) and general characteristics, including impacts such as density of non-native riparian trees. At the family level, aquatic macroinvertebrate communities showed variation between sites and seasons. Differences were more pronounced on the basis of natural land cover type (fynbos versus indigenous forest) than densities of non-native invasive riparian vegetation. Conservation of these river systems will depend on maintaining a mosaic of natural vegetation types. 相似文献
128.
Experimental RNomics: identification of 140 candidates for small non-messenger RNAs in the plant Arabidopsis thaliana 总被引:13,自引:0,他引:13
Marker C Zemann A Terhörst T Kiefmann M Kastenmayer JP Green P Bachellerie JP Brosius J Hüttenhofer A 《Current biology : CB》2002,12(23):2002-2013
BACKGROUND: Genomes from all organisms known to date express two types of RNA molecules: messenger RNAs (mRNAs), which are translated into proteins, and non-messenger RNAs, which function at the RNA level and do not serve as templates for translation. RESULTS: We have generated a specialized cDNA library from Arabidopsis thaliana to investigate the population of small non-messenger RNAs (snmRNAs) sized 50-500 nt in a plant. From this library, we identified 140 candidates for novel snmRNAs and investigated their expression, abundance, and developmental regulation. Based on conserved sequence and structure motifs, 104 snmRNA species can be assigned to novel members of known classes of RNAs (designated Class I snmRNAs), namely, small nucleolar RNAs (snoRNAs), 7SL RNA, U snRNAs, as well as a tRNA-like RNA. For the first time, 39 novel members of H/ACA box snoRNAs could be identified in a plant species. Of the remaining 36 snmRNA candidates (designated Class II snmRNAs), no sequence or structure motifs were present that would enable an assignment to a known class of RNAs. These RNAs were classified based on their location on the A. thaliana genome. From these, 29 snmRNA species located to intergenic regions, 3 located to intronic sequences of protein coding genes, and 4 snmRNA candidates were derived from annotated open reading frames. Surprisingly, 15 of the Class II snmRNA candidates were shown to be tissue-specifically expressed, while 12 are encoded by the mitochondrial or chloroplast genome. CONCLUSIONS: Our study has identified 140 novel candidates for small non-messenger RNA species in the plant A. thaliana and thereby sets the stage for their functional analysis. 相似文献
129.
rII cistrons of bacteriophage T4. DNA sequence around the intercistronic divide and positions of genetic landmarks 总被引:35,自引:0,他引:35
D Pribnow D C Sigurdson L Gold B S Singer C Napoli J Brosius T J Dull H F Noller 《Journal of molecular biology》1981,149(3):337-376
An 873 base-pair DNA sequence from the rII region of bacteriophage T4 is presented. The sequence encodes 139 carboxyl-terminal amino acids of rIIA and the amino-terminal 146 amino acids of rIIB. Eleven base-pairs separate the rIIA stop codon (UAA) and the rIIB AUG.An extensive genetic map is superimposed on the DNA sequence, showing the deduced locations of many of the mutations (base-pair substitutions, frameshifts, deletions) found in previous rII genetic studies. 相似文献
130.
Quantitative genomics of locomotor behavior in <Emphasis Type="Italic">Drosophila melanogaster</Emphasis> 总被引:1,自引:0,他引:1