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991.
Siran Zhu Nila Roy Choudhury Saul Rooney Nhan T Pham Joanna Koszela David Kelly Christos Spanos Juri Rappsilber Manfred Auer Gracjan Michlewski 《Nucleic acids research》2021,49(11):6456
RNA–protein interactions are central to all gene expression processes and contribute to a variety of human diseases. Therapeutic approaches targeting RNA–protein interactions have shown promising effects on some diseases that are previously regarded as ‘incurable’. Here, we developed a fluorescent on-bead screening platform, RNA Pull-Down COnfocal NAnoscanning (RP-CONA), to identify RNA–protein interaction modulators in eukaryotic cell extracts. Using RP-CONA, we identified small molecules that disrupt the interaction between HuR, an inhibitor of brain-enriched miR-7 biogenesis, and the conserved terminal loop of pri-miR-7–1. Importantly, miR-7′s primary target is an mRNA of α-synuclein, which contributes to the aetiology of Parkinson’s disease. Our method identified a natural product quercetin as a molecule able to upregulate cellular miR-7 levels and downregulate the expression of α-synuclein. This opens up new therapeutic avenues towards treatment of Parkinson’s disease as well as provides a novel methodology to search for modulators of RNA–protein interaction. 相似文献
992.
993.
Shekhar R. Biswas Azim U. Mallik Junaid K. Choudhury Ainun Nishat 《Wetlands Ecology and Management》2009,17(4):365-383
The effect of intensive human intervention, poor socio-economic conditions and little knowledge on mangrove ecology pose enormous
challenges for mangrove restoration in Southeast Asia. We present a framework for tropical mangrove restoration. Our proposed
restoration framework addresses the ecology, economy and social issues simultaneously by considering the causes of mangrove
degradation. We provide a step by step guideline for its restoration. We argue that although, ecological issues are of prime
importance, economic and social issues must be considered in the restoration plan in order for it to be successful. Since
mangrove ecology is not adequately studied in this region, local ecological knowledge can be used to fill the baseline information
gaps. Unwanted human disturbance can be minimized by encouraging community participation. This can be ensured and sustained
by facilitating the livelihood of the coastal community. We translated the restoration paradigm into a readily available practical
guideline for the executors of the plans. We provide an example of mangrove restoration project that is closely related to
our proposed framework. We are optimistic that this framework has the potential for universal application with necessary adjustments. 相似文献
994.
Pamela Reinagel 《PloS one》2013,8(6)
Animals must continuously evaluate sensory information to select the preferable among possible actions in a given context, including the option to wait for more information before committing to another course of action. In experimental sensory decision tasks that replicate these features, reaction time distributions can be informative about the implicit rules by which animals determine when to commit and what to do. We measured reaction times of Long-Evans rats discriminating the direction of motion in a coherent random dot motion stimulus, using a self-paced two-alternative forced-choice (2-AFC) reaction time task. Our main findings are: (1) When motion strength was constant across trials, the error trials had shorter reaction times than correct trials; in other words, accuracy increased with response latency. (2) When motion strength was varied in randomly interleaved trials, accuracy increased with motion strength, whereas reaction time decreased. (3) Accuracy increased with reaction time for each motion strength considered separately, and in the interleaved motion strength experiment overall. (4) When stimulus duration was limited, accuracy improved with stimulus duration, whereas reaction time decreased. (5) Accuracy decreased with response latency after stimulus offset. This was the case for each stimulus duration considered separately, and in the interleaved duration experiment overall. We conclude that rats integrate visual evidence over time, but in this task the time of their response is governed more by elapsed time than by a criterion for sufficient evidence. 相似文献
995.
The formation and maintenance of cell-cell junctions, both under physiological and pathological conditions, requires the targeting and trafficking of junctional proteins. Proteins of the syntaxin (Stx)-family localize to a variety of subcellular membranes and contribute to intracellular transport of cargo by regulating vesicle fusion events at these sites. Unlike plasma membrane localized Stxs, the roles of endosome- and Golgi-localized stx proteins in epithelial morphogenesis are less understood. Here we show that Stx16– an endosome- and Golgi-localized target-membrane soluble N-ethylmaleimide attachment protein receptor (t-SNARE) that plays a role in membrane trafficking between these compartments – is essential for lumen development. In cultured Madin Darby Canine Kidney (MDCK) cells, Stx16 was selectively upregulated as sparsely plated cells attained confluency. Stx16-depleted confluent monolayers consistently showed lower transepithelial resistance than control monolayers, and failed to maintain endogenous and ectopically expressed E-cadherin at the adherens junctions due to decreased recycling. We further found that whereas cysts formed by MDCK cells cultured in Matrigel have a single hollow lumen, those formed by stx16-depleted counterparts had multiple lumens, due to abnormal orientiation of the mitotic spindle. Finally, a similar role for stx16 function in vivo is indicated by our analysis of pronephric-duct development in zebrafish expressing the claudinB:lynGFP transgene; lack of stx16 function in this structure (in stx16-morphant embryos) led to the development of enlarged, torturous pronephric ducts with more than one lumen. Taken together, our in vitro and in vivo studies establish a role for Stx16 in maintaining the integrity of cell-cell junctions, and thereby in morphogenesis of the kidney epithelial lumen. 相似文献
996.
997.
Because homosporous pteridophytes (Psilotophyta, Arthrophyta, most Microphyllophyta and Pteridophyta) produce bisexual gametophytes, it was maintained that high levels of inbreeding would characterize these plants. Electrophoretic evidence was used to estimate the frequency of intragametophytic selfing in Equisetum arvense (Arthrophyta). A total of 669 samples from 17 populations was examined from western North America. Although some populations exhibited as many as seven or eight genotypes, 10 populations were each characterized by only a single genotype; eight of these populations were heterozygous for one or more loci. For most populations, estimates of intragametophytic self-fertilization are 0.000, indicating that virtually all matings involve different gametophytes. Genetic data corroborate predictions based on earlier field and laboratory investigations of Equisetum gametophytes. These detailed studies demonstrated that in many species, including E. arvense, gametophytes are initially either male or female; only later and in the absence of fertilization do some gametophytes become bisexual. Our findings join a growing electrophoretic data base which demonstrates that homosporous pteridophytes are not highly inbreeding as previously suggested. 相似文献
998.
999.
Variation in foliar δ13C in Hawaiian Metrosideros polymorpha: a case of internal resistance? 总被引:11,自引:0,他引:11
Summary Sun leaves of Metrosideros polymorpha were collected in 51 sites on 9 lava flows that represented gradients of elevation, precipitation, substrate age, and substrate texture on Mauna Loa volcano, Hawai'i. Leaf mass per unit leaf area increased with increasing elevation on all flows, while foliar nitrogen concentration decreased with increasing elevation and increased with increasing substrate age. Foliar 13C became less negative with increasing elevation on the wet east-side lava flows, but not the dry northwest-side flows; it did not reflect patterns of precipitation or presumed water availability. 13C was very strongly correlated with leaf mass per area across all of the sites. Limited gas-exchange information suggested that calculated ci/ca did not decrease with elevation in association with less-negative 13C, and photosynthesis per unit of nitrogen was significantly reduced in high-elevation plants. These results are consistent with a substantial internal resistance to CO2 diffusion in the thick Metrosideros polymorpha leaves in high elevation sites.Published as a contribution to the International Union for Biological Sciences Tropical Mountain Ecosystems Program, and as Carnegie Institution of Washington Department of Plant Biology Publication Number 1065 相似文献
1000.