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91.
We sought to evaluate the extent of the contribution of transposable elements (TEs) to human microRNA (miRNA) genes along with the evolutionary dynamics of TE-derived human miRNAs. We found 55 experimentally characterized human miRNA genes that are derived from TEs, and these TE-derived miRNAs have the potential to regulate thousands of human genes. Sequence comparisons revealed that TE-derived human miRNAs are less conserved, on average, than non-TE-derived miRNAs. However, there are 18 TE-derived miRNAs that are relatively conserved, and 14 of these are related to the ancient L2 and MIR families. Comparison of miRNA vs. mRNA expression patterns for TE-derived miRNAs and their putative target genes showed numerous cases of anti-correlated expression that are consistent with regulation via mRNA degradation. In addition to the known human miRNAs that we show to be derived from TE sequences, we predict an additional 85 novel TE-derived miRNA genes. TE sequences are typically disregarded in genomic surveys for miRNA genes and target sites; this is a mistake. Our results indicate that TEs provide a natural mechanism for the origination miRNAs that can contribute to regulatory divergence between species as well as a rich source for the discovery of as yet unknown miRNA genes. 相似文献
92.
Transgenic cotton expressing Cry10Aa toxin confers high resistance to the cotton boll weevil 下载免费PDF全文
Thuanne Pires Ribeiro Fabricio Barbosa Monteiro Arraes Isabela Tristan Lourenço‐Tessutti Marilia Santos Silva Maria Eugênia Lisei‐de‐Sá Wagner Alexandre Lucena Leonardo Lima Pepino Macedo Janaina Nascimento Lima Regina Maria Santos Amorim Sinara Artico Márcio Alves‐Ferreira Maria Cristina Mattar Silva Maria Fatima Grossi‐de‐Sa 《Plant biotechnology journal》2017,15(8):997-1009
93.
Bonjardim LR Cunha ES Guimarães AG Santana MF Oliveira MG Serafini MR Araújo AA Antoniolli AR Cavalcanti SC Santos MR Quintans-Júnior LJ 《Zeitschrift für Naturforschung. C, Journal of biosciences》2012,67(1-2):15-21
We attempted to identify the antinociceptive and anti-inflammatory actions of the monoterpene p-cymene. Firstly, behavioural screening was carried out to verify the influence of p-cymene [25, 50, and 100 mg/kg intraperitoneal (i.p.)] on the central nervous system (CNS) activity. The antinociceptive activity of p-cymene was evaluated by the acetic acid-induced writhing response, formalin, and hot-plate test, respectively. The leukocyte migration induced by injection of carrageenan was used to assess the anti-inflammatory activity. p-Cymene showed depressant activity on CNS after 4 h of treatment and also a possible action on the autonomous nervous system (ANS), mainly at the dose of 100 mg/kg (i.p.). It was found that p-cymene (50 and 100 mg/kg, i.p.) significantly (p < 0.05) reduced the writhing responses induced by acetic acid. p-Cymene also decreased the licking time in the first and second phase, respectively, of the formalin test. The results of the hot-plate test showed that all doses of p-cymene increased significantly the latency time of the response to the thermal stimulus in both licking and jumping parameters. In addition, there was a significantly (p < 0.05) decreased leukocyte migration at all doses of p-cymene. The experimental data demonstrate that p-cymene possesses antinociceptive and anti-inflammatory activities. 相似文献
94.
Karla F.A.S. Silva Miguel Michereff‐Filho Maria E.N. Fonseca José G. Silva‐Filho Ana C.A. Texeira Antônio Williams Moita Jorge B. Torres Rafael Fernández‐Muñoz Leonardo S. Boiteux 《Entomologia Experimentalis et Applicata》2014,151(3):218-230
Advances in tomato breeding for pest resistance have been achieved via gene introgression from wild Solanum (section Lycopersicon) species (Solanaceae). Ninety‐nine F3 families derived from an interspecific cross using as parental lines Solanum lycopersicum L. ‘LAM‐148' (susceptible standard) and Solanum pimpinellifolium L. ‘TO‐937‐15’ (multiple pest resistance accession with type IV glandular trichomes and acylsugar accumulation) were evaluated for their resistance against the whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) biotype B in free‐choice and no‐choice tests for oviposition and adult colonization. The parental lines and eight F3 families with contrasting levels of resistance against the whitefly were selected and investigated in additional assays, which included the estimation of trichome densities and foliar acylsugar levels. The F3 families BTR‐302 and BTR‐331 exhibited low amounts of eggs of whitefly and transgressive segregation for type IV glandular trichome density with values greater than that of TO‐937‐15 plants. However, the tested families did not surpass the total foliar acylsugar content found in TO‐937‐15. BTR‐331 exhibited low colonization in the free‐choice test and it was the least preferred F3 family in the no‐choice test. The higher resistance levels of BTR‐331 were associated with a positive combination of higher type IV trichome density and higher acylsugar levels. Some F3 families displayed reduced fruit set due to the presence of flowers with style exertion of the antheridial‐cone. Fruit weight at harvest stage of the selected families (from 4.9 to 14.5 g) was lower than that of LAM‐148 (139.5 g) but higher than that of TO‐937‐15 plants (1.3 g). Therefore, although difficult to reach due to the simultaneous segregation of many polygenic traits, the combination of high B. tabaci resistance levels with superior horticultural traits is feasible. These results confirm TO‐937‐15 as a source of biotype B resistance. From the breeding standpoint, the genetic similarity between S. lycopersicum and S. pimpinellifolium would allow a more efficient resistance introgression by facilitating recombination and minimizing the potentially undesirable linkage drag associated with this trait. 相似文献
95.
Rodolfo Valdés Andrés Tamayo Marcos González Sigifredo Padilla Déborah Geada William Ferro Lorely Milá Leonardo Gómez Rosario Alemán Alberto Leyva Cristina García Otto Mendoza Tatiana Alvarez Lamay Dorta Yanet Villega Dobián Cecilia Hasel Aragón Tatiana González Maylín La O Jorge López 《Biotechnology and Bioprocess Engineering》2012,17(1):145-159
Monoclonal antibody (mAb) production methods (ascites, in vitro technologies, transgenic animals, and dicot or monocot transgenic plants; moss, algae) have been improved since they were first developed in 1975. In this study, we illustrate a summary of a study case in which mice, a hollow fiber system, and tobacco transgenic plants were assessed for the production of mAb for vaccine manufacturing and vaccine production. 相似文献
96.
Leonardo A Pinto Martin Depner Norman Klopp Thomas Illig Christian Vogelberg Erika von Mutius Michael Kabesch 《Respiratory research》2010,11(1):23
Background
Atopic and non-atopic wheezing may be caused by different etiologies: while eosinophils are more important in atopic asthmatic wheezers, neutrophils are predominantly found in BAL samples of young children with wheezing. Both neutrophils as well as eosinophils may secrete matrix metalloproteinase 9 (MMP-9). Considering that MMP-9 plays an important role in airway wall thickening and airway inflammation, it may influence the development of obstructive airway phenotypes in children. In the present study we investigated whether genetic variations in MMP-9 influence the development of different forms of childhood asthma.Methods
Genotyping of four HapMap derived tagging SNPs in the MMP-9 gene was performed using MALDI-TOF MS in three cross sectional study populations of German children (age 9-11; N = 4,264) phenotyped for asthma and atopic diseases according to ISAAC standard procedures. Effects of single SNPs and haplotypes were studied using SAS 9.1.3 and Haploview.Results
SNP rs2664538 significantly increased the risk for non-atopic wheezing (OR 2.12, 95%CI 1.40-3.21, p < 0.001) and non-atopic asthma (OR 1.66, 95%CI 1.12-2.46, p = 0.011). Furthermore, the minor allele of rs3918241 may be associated with decreased expiratory flow measurements in non-atopic children. No significant effects on the development of atopy or total serum IgE levels were observed.Conclusions
Our results have shown that homozygocity for MMP-9 variants increase the risk to develop non-atopic forms of asthma and wheezing, which may be explained by a functional role of MMP-9 in airway remodeling. These results suggest that different wheezing disorders in childhood are affected differently by genetic alterations. 相似文献97.
Fernanda Abreu Alioscka A. Sousa Maria A. Aronova Youngchan Kim Daniel Cox Richard D. Leapman Leonardo R. Andrade Bechara Kachar Dennis A. Bazylinski Ulysses Lins 《Journal of structural biology》2013,181(2):162-168
We examined the structure and biomineralization of prismatic magnetosomes in the magnetotactic marine vibrio Magnetovibrio blakemorei strain MV-1 and a non-magnetotactic mutant derived from it, using a combination of cryo-electron tomography and freeze-fracture. The vesicles enveloping the Magnetovibrio magnetosomes were elongated and detached from the cell membrane. Magnetosome crystal formation appeared to be initiated at a nucleation site on the membrane inner surface. Interestingly, while scattered filaments were observed in the surrounding cytoplasm, their association with the magnetosome chains could not be unequivocally established. Our data suggest fundamental differences between prismatic and octahedral magnetosomes in their mechanisms of nucleation and crystal growth as well as in their structural relationships with the cytoplasm and plasma membrane. 相似文献
98.
99.
Squatrito M Mancino M Sala L Draetta GF 《Biochemical and biophysical research communications》2006,344(3):859-868
dsRNA-binding domains (dsRBDs) characterize an expanding family of proteins involved in different cellular processes, ranging from RNA editing and processing to translational control. Here we present evidence that Ebp1, a cell growth regulating protein that is part of ribonucleoprotein (RNP) complexes, contains a dsRBD and that this domain mediates its interaction with dsRNA. Deletion of Ebp1's dsRBD impairs its localization to the nucleolus and its ability to form RNP complexes. We show that in the cytoplasm, Ebp1 is associated with mature ribosomes and that it is able to inhibit the phosphorylation of serine 51 in the eukaryotic initiation factor 2 alpha (eIF2alpha). In response to various cellular stress, eIF2alpha is phosphorylated by distinct protein kinases (PKR, PERK, GCN2, and HRI), and this event results in protein translation shut-down. Ebp1 overexpression in HeLa cells is able to protect eIF2alpha from phosphorylation at steady state and also in response to various treatments. We demonstrate that Ebp1 interacts with and is phosphorylated by the PKR protein kinase. Our results demonstrate that Ebp1 is a new dsRNA-binding protein that acts as a cellular inhibitor of eIF2alpha phosphorylation suggesting that it could be involved in protein translation control. 相似文献
100.
Cristie Grazziotin Noschang Rachel Krolow Leticia Ferreira Pettenuzzo Mônica Colpini Ávila Andrelisa Fachin Danusa Arcego Eduardo von Pozzer Toigo Leonardo Machado Crema Luísa Amália Diehl Deusa Vendite Carla Dalmaz 《Neurochemical research》2009,34(9):1568-1574
We studied the effect of chronic caffeine on parameters related to oxidative stress in different brain regions of stressed
and non-stressed rats. Wistar rats were divided into three groups: control (receiving water), caffeine 0.3 g/L and caffeine
1.0 g/L (in the drinking water). These groups were subdivided into non-stressed and stressed (repeated restraint stress during
40 days). Lipid peroxide levels and the total radical-trapping potential were assessed, as well as antioxidant enzyme activities
superoxide dismutase, gluthatione peroxidase, and catalase in hippocampus, striatum and cerebral cortex. Results showed interactions
between stress and caffeine, especially in the cerebral cortex, since caffeine increased the activity of some antioxidant
enzymes, but not in stressed animals. We concluded that chronic administration of caffeine led, in some cases, to increased
activity of antioxidant enzymes. However, these effects were not observed in the stressed animals. 相似文献