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991.
Targeting cleavage and polyadenylation specific factor 1 via shRNA inhibits cell proliferation in human ovarian cancer 总被引:1,自引:0,他引:1
Cleavage and polyadenylation specificity factor 1 (CPSF1), a member of CPSF complex, has been reported to play a key role in pre-mRNA 3′-end formation, but its possible role in ovarian cancer remains unclear. In the present study, we found the mRNA level of CPSF1 was overexpressed in ovarian cancer tissues using Oncomine Cancer Microarray database. Then the loss-of-function assays, including CCK-8, colony formation and flow cytometry assays, were performed to determine the effects of CPSF1 on cell viability, proliferation, cell cycle and apoptosis of human ovarian cancer cell lines (SKOV-3 and OVCAR-3). The results indicated that depletion of CPSF1 suppressed cell viability, impaired colony formation ability, induced cell cycle arrest at G0/G1 phase and promoted cell apoptosis in ovarian cancer cells. Furthermore, knockdown of CPSF1 upregulated the expression of cleaved caspase-3 and PARP and downregulated CDK4/cyclin D1 expression. These data suggested that CPSF1 could promote ovarian cancer cell growth and proliferation in vitro and its depletion might serve as a potential therapeutic target for human ovarian cancer. 相似文献
992.
Sarah A. Cocherell Stephanie N. Chun Dennis E. Cocherell Lisa C. Thompson A. Peter Klimley Joseph J. CechJr. 《Environmental Biology of Fishes》2012,93(1):143-150
In regulated rivers, fluctuating water depths associated with pulsed discharges may strand small fish in side channels and
pools. Quantitative assessments of stranded fish are difficult in field studies (e.g., due to unknown effects of avian and
terrestrial vertebrate predators). To assess such lateral displacement and stranding on juvenile stream fishes, we designed,
constructed, and tested (with three species) a 2 × 1-m, lateral-displacement flume. The flume featured a main channel that
never drained and a raised, wide “floodplain” channel that alternately flooded, with a simulated pulse, and became dewatered.
The floodplain contained four pools, with different shapes and draining capacities, in which fish could become stranded as
the water level subsided. Fish-stranding rates (8%) in this relatively compact laboratory flume, after exposure to simulated
pulsed stream flows, were comparable to those observed in past investigations using larger, artificial streams. 相似文献
993.
Torre J. Hovick Brady W. Allred Devan A. McGranahan Michael W. Palmer R. Dwayne Elmore Samuel D. Fuhlendorf 《Biodiversity and Conservation》2016,25(2):345-356
A species distribution combines the resources and climatic tolerances that allow an individual or population to persist. As these conditions change, one mechanism to maintain favorable resources is for an organism to shift its range. Much of the research examining range shifts has focused on dynamic distribution boundaries wheras the role of species breeding habitat or migration strategies on shift tendencies has received less attention. We expand on previous research by using a large suite of avian species (i.e., 277), analyzing observed abundance-weighted average latitudes, and categorizing species by breeding environment and migration strategy. We used the North American Breeding Bird Survey dataset to address two questions: (1) Has the center of observed abundance for individual species shifted latitudinally? (2) Is there a relationship between migration strategy or breeding habitat and range shifts? Results indicate the majority of species have experienced poleward range shifts over the last 43 years, and birds breeding in all habitat showed trends of poleward shift but only those species breeding in scrub-shrub and grassland environments were different from zero. Additionally, species that are short distance migrants are experiencing significant poleward shifts while Neotropical and permanent residents had shifts that were not different from zero. Our findings do support the general trend expected from climate driven changes (i.e., > 52 % shifting poleward), however, the proportion of species exhibiting equatorial shifts (24 %) or no significant shifts (23 %) illustrates the complex interplay between land cover, climate, species interactions, and other forces that can interact to influence breeding ranges over time. Regardless of the mechanisms driving range shifts, our findings emphasize the need for connecting and expanding habitats for those species experiencing range shifts. This research describes the patterns of breeding birds through central North America and we encourage future research to focus on the mechanisms driving these patterns. 相似文献
994.
Singh S D'mello V van Bergen en Henegouwen P Birge RB 《Biochemical and biophysical research communications》2007,364(3):540-548
Integrin receptors are heterodimeric transmembrane receptors with critical functions in cell adhesion and migration, cell cycle progression, differentiation, apoptosis, and phagocytosis of apoptotic cells. Integrins are activated by intracellular signaling that alter the binding affinity for extracellular ligands, so-called inside to outside signaling. A common element for integrin activation involves binding of the cytoskeletal protein talin, via its FERM domain, to a highly conserved NPxY motif in the β chain cytoplasmic tails, which is involved in long-range conformation changes to the extracellular domain that impinges on ligand affinity. When the human beta-5 (β5) integrin cDNA was expressed in αv positive, β5 and β3 negative hamster CS-1 cells, it promoted NPxY-dependent adhesion to VTN-coated surfaces, phosphorylation of FAK, and concomitantly, β5 integrin-EGFP protein was recruited into talin and paxillin-containing focal adhesions. Expression of a NPxY destabilizing β5 mutant (Y750A) abrogated adhesion and β5-Y750A-EGFP was excluded from focal adhesions at the tips of stress fibers. Surprisingly, expression of β5 Y750A integrin had a potent gain-of-function effect on apoptotic cell phagocytosis, and further, a β5-Y750A-EGFP fusion integrin readily bound MFG-E8-coated 10 μm diameter microspheres developed as apoptotic cell mimetics. The critical sequences in β5 integrin were mapped to a YEMAS motif just proximal to the NPxY motif. Our studies suggest that the phagocytic function of β5 integrin is regulated by an unconventional NPxY-talin-independent activation signal and argue for the existence of molecular switches in the β5 cytoplasmic tail for adhesion and phagocytosis. 相似文献
995.
Syeda Mehpara Farhat Aamra Mahboob Ghazala Iqbal Touqeer Ahmed 《Biological trace element research》2017,177(1):115-121
Aluminum is associated with etiology of many neurodegenerative diseases specially Alzheimer’s disease. Chronic exposure to aluminum via drinking water results in aluminum deposition in the brain that leads to cognitive deficits. The study aimed to determine the effects of aluminum on cholinergic biomarkers, i.e., acetylcholine level, free choline level, and choline acetyltransferase gene expression, and how cholinergic deficit affects novel object recognition and sociability in mice. Mice were treated with AlCl3 (250 mg/kg). Acetylcholine level, free choline level, and choline acetyltransferase gene expression were determined in cortex, hippocampus, and amygdala. The mice were subjected to behavior tests (novel object recognition and social novelty preference) to assess memory deficits. The acetylcholine level in cortex and hippocampus was significantly reduced in aluminum-treated animals, as compared to cortex and hippocampus of control animals. Acetylcholine level in amygdala of aluminum-treated animals remained unchanged. Free choline level in all the three brain parts was found unaltered in aluminum-treated mice. The novel object recognition memory was severely impaired in aluminum-treated mice, as compared to the control group. Similarly, animals treated with aluminum showed reduced sociability compared to the control mice group. Our study demonstrates that aluminum exposure via drinking water causes reduced acetylcholine synthesis in spite of normal free choline availability. This deficit is caused by reduced recycling of acetylcholine due to lower choline acetyltransferase level. This cholinergic hypofunction leads to cognitive and memory deficits. Moreover, hippocampus is the most affected brain part after aluminum intoxication. 相似文献
996.
With the aim to explore the possible role of phosphate-solubilizing bacteria (PSB) in phosphorus (P) cycling in agricultural soils, we isolated PSB inhabiting naturally in the sandy loam soils under chickpea cropping of Patiala (Punjab State). A total of 31 bacterial isolates showing solubilizing activities were isolated on Pikovskaya agar plates. The potent phosphate solubilizers were selected for further characterization. These isolates were shown to belong to the genera Pseudomonas and Serratia by partial sequencing analysis of their respective 16S rDNA genes. ERIC-PCR based fingerprinting was done for tracking the survival of introduced populations of the PSB during mass inoculation of these strains under chickpea plots. The results showed positive correlation (r2 = 0.853) among soil phosphatase activity and phosphate solubilizers population, which was also positively correlated (r2 = 0.730) to available phosphorus. Identification and characterization of soil PSB for the effective plant growth-promotion broadens the spectrum of phosphate solubilizers available for field application. 相似文献
997.
Analysis of trehalose-6-phosphate synthase (TPS) gene family suggests the formation of TPS complexes in rice 总被引:2,自引:0,他引:2
Trehalose-6-phosphate (T6P), an intermediate in the trehalose biosynthesis pathway, is emerging as an important regulator
of plant metabolism and development. T6P levels are potentially modulated by a group of trehalose-6-phosphate synthase (TPS)
and trehalose-6-phosphate phosphatase (TPP) homologues. In this study, we have isolated 11 TPS genes encoding proteins with both TPS and TPP domains, from rice. Functional complement assays performed in yeast tps1 and tps2 mutants, revealed that only OsTPS1 encodes an active TPS enzyme and no OsTPS protein possesses TPP activity. By using a yeast two-hybrid analysis, a complicated
interaction network occurred among OsTPS proteins, and the TPS domain might be essential for this interaction to occur. The
interaction between OsTPS1 and OsTPS8 in vivo was confirmed by bimolecular fluorescence complementation and coimmunoprecipitation
assays. Furthermore, our gel filtration assay showed that there may exist two forms of OsTPS1 (OsTPS1a and OsTPS1b) with different
elution profiles in rice. OsTPS1b was particularly cofractionated with OsTPS5 and OsTPS8 in the 360 kDa complex, while OsTPS1a
was predominantly incorporated into the complexes larger than 360 kDa. Collectively, these results suggest that OsTPS family members may form trehalose-6-phosphate synthase complexes and therefore potentially modify T6P levels to regulate
plant development. 相似文献
998.
Miyamoto K Okunishi M Nukui E Tsuchiya T Kobayashi T Imada C Tsujibo H 《Archives of microbiology》2007,188(6):619-628
999.
Molecular markers for four leaf rust resistance genes introgressed into wheat from wild relatives. 总被引:12,自引:0,他引:12
Near-isolines carrying four different genes for resistance to leaf rust were used to find linked molecular markers for these genes. Clones used to detect polymorphism were selected on the basis of the reported chromosomal location of the resistance genes. Both Lophopyron-derived resistance genes, Lr19 and Lr24, cosegregated with eight molecular markers assigned to chromosomes 7DL and 3DL, respectively. One clone cosegregated with Lr9 and two closely linked RFLP markers were found for Lr32, mapping at 3.3 +/- 2.6 and 6.9 +/- 3.6 cM from the resistance gene. The Lophopyron-chromatin segment in isolines carrying chromosomes 7E (Lr19) and 3E (Lr24) replaced a large portion of chromosome 7D and the distal portion of chromosome 3D, respectively. Clones assigned to these chromosomes on the basis of aneuploid analysis hybridized to 7E and 3E segments, thus confirming cytological results that these introgressed segments represent homoeologous chromosomes. The linked RFLP markers could be used to identify the resistance genes and generate new combinations in breeding populations, especially in the absence of disease in the environment or when virulence is lacking. 相似文献
1000.
Kanwar SS Verma HK Pathak S Kaushal RK Kumar Y Verma ML Chimni SS Chauhan GS 《Acta microbiologica et immunologica Hungarica》2006,53(2):195-207
A purified alkaline thermo-tolerant bacterial lipase from Pseudomonas aeruginosa MTCC-4713 was immobilized on a poly (AAc-co-HPMA-cl-MBAm) hydrogel. The hydrogel-bound lipase achieved 93.6% esterification of ethanol and propionic acid (300 mM: 100 mM) into ethyl propionate at temperature 65 degrees C in 3 h in the presence of a molecular sieve (3 angstroms). In contrast, hydrogel-immobilized lipase pre-exposed to 5 mM of HgCl2 orNH4Cl resulted in approximately 97% conversion of reactants in 3 h into ethyl propionate under identical conditions. The salt-exposed hydrogel was relatively more efficient in repetitive esterification than the hydrogel-bound lipase not exposed to any of the cations. Moreover, bound lipase exposed Hg2+ or NH4+ ions showed altered specificity towards p-nitrophenyl esters and was more hydrolytic towards higher C-chain p-nitrophenyl esters (p-nitrophenyl laurate and p-nitrophenyl palmitate with C 12 and C 16 chain) than the immobilized lipase not exposed to any of the salts. The later showed greater specificity towards p-nitrophenyl caprylate (C 8). 相似文献