Somatic localization of a specific large-conductance calcium-activated potassium channel subtype controls compartmentalized ethanol sensitivity in the nucleus accumbens

Alcohol is an addictive drug that targets a variety of ion channels and receptors. To address whether the effects of alcohol are compartment specific (soma vs dendrite), we examined the effects of ethanol (EtOH) on large-conductance calcium-activated potassium channels (BK) in cell bodies and dendrites of freshly isolated neurons from the rat nucleus accumbens (NAcc), a region known to be critical for the development of addiction. Compartment-specific drug action was indeed observed. Clinically relevant concentrations of EtOH increased somatic but not dendritic BK channel open probability. Electrophysiological single-channel recordings and pharmacological analysis of the BK channel in excised patches from each region indicated a number of differences, suggestive of a compartment-specific expression of the beta4 subunit of the BK channel, that might explain the differential alcohol sensitivity. These parameters included activation kinetics, calcium dependency, and toxin blockade. Reverse transcription-PCR showed that both BK channel beta1 and beta4 subunit mRNAs are found in the NAcc, although the signal for beta1 is significantly weaker. Immunohistochemistry revealed that beta1 subunits were found in both soma and dendrites, whereas beta4 appeared restricted to the soma. These findings suggest that the beta4 subunit may confer EtOH sensitivity to somatic BK channels, whereas the absence of beta4 in the dendrite results in insensitivity to the drug. Consistent with this idea, acute EtOH potentiated alphabeta4 BK currents in transfected human embryonic kidney cells, whereas it failed to alter alphabeta1 BK channel-mediated currents. Finally, an EtOH concentration (50 mm) that increased BK channel open probability strongly decreased the duration of somatic-generated action potential in NAcc neurons

Overexpression of miR-128 specifically inhibits the truncated isoform of NTRK3 and upregulates BCL2 in SH-SY5Y neuroblastoma cells

<p>Abstract</p> <p>Background</p> <p>Neurotrophins and their receptors are key molecules in the regulation of neuronal differentiation and survival. They mediate the survival of neurons during development and adulthood and are implicated in synaptic plasticity. The human neurotrophin-3 receptor gene <it>NTRK3 </it>yields two major isoforms, a full-length kinase-active form and a truncated non-catalytic form, which activates a specific pathway affecting membrane remodeling and cytoskeletal reorganization. The two variants present non-overlapping 3'UTRs, indicating that they might be differentially regulated at the post-transcriptional level. Here, we provide evidence that the two isoforms of <it>NTRK3 </it>are targeted by different sets of microRNAs, small non-coding RNAs that play an important regulatory role in the nervous system.</p> <p>Results</p> <p>We identify one microRNA (miR-151-3p) that represses the full-length isoform of <it>NTRK3 </it>and four microRNAs (miR-128, miR-485-3p, miR-765 and miR-768-5p) that repress the truncated isoform. In particular, we show that the overexpression of miR-128 - a brain enriched miRNA - causes morphological changes in SH-SY5Y neuroblastoma cells similar to those observed using an siRNA specifically directed against truncated <it>NTRK3</it>, as well as a significant increase in cell number. Accordingly, transcriptome analysis of cells transfected with miR-128 revealed an alteration of the expression of genes implicated in cytoskeletal organization as well as genes involved in apoptosis, cell survival and proliferation, including the anti-apoptotic factor <it>BCL2</it>.</p> <p>Conclusions</p> <p>Our results show that the regulation of <it>NTRK3 </it>by microRNAs is isoform-specific and suggest that neurotrophin-mediated processes are strongly linked to microRNA-dependent mechanisms. In addition, these findings open new perspectives for the study of the physiological role of miR-128 and its possible involvement in cell death/survival processes.</p

A global spectral library to characterize the world's soil

Soil provides ecosystem services, supports human health and habitation, stores carbon and regulates emissions of greenhouse gases. Unprecedented pressures on soil from degradation and urbanization are threatening agro-ecological balances and food security. It is important that we learn more about soil to sustainably manage and preserve it for future generations. To this end, we developed and analyzed a global soil visible-near infrared (vis-NIR) spectral library. It is currently the largest and most diverse database of its kind. We show that the information encoded in the spectra can describe soil composition and be associated to land cover and its global geographic distribution, which acts as a surrogate for global climate variability. We also show the usefulness of the global spectra for predicting soil attributes such as soil organic and inorganic carbon, clay, silt, sand and iron contents, cation exchange capacity, and pH. Using wavelets to treat the spectra, which were recorded in different laboratories using different spectrometers and methods, helped to improve the spectroscopic modelling. We found that modelling a diverse set of spectra with a machine learning algorithm can find the local relationships in the data to produce accurate predictions of soil properties. The spectroscopic models that we derived are parsimonious and robust, and using them we derived a harmonized global soil attribute dataset, which might serve to facilitate research on soil at the global scale. This spectroscopic approach should help to deal with the shortage of data on soil to better understand it and to meet the growing demand for information to assess and monitor soil at scales ranging from regional to global. New contributions to the library are encouraged so that this work and our collaboration might progress to develop a dynamic and easily updatable database with better global coverage. We hope that this work will reinvigorate our community's discussion towards larger, more coordinated collaborations. We also hope that use of the database will deepen our understanding of soil so that we might sustainably manage it and extend the research outcomes of the soil, earth and environmental sciences towards applications that we have not yet dreamed of

Zmiany bialek a dlugotrwale przechowywanie grasicy

Celem pracy było określenie wpływu długoterminowego przechowywania, a także technologii utrwalania grasicy (zamrażanie oraz składowanie w temperaturze -12 i -30°C i liofilizacja) na jej przydatność jako surowca farmaceutycznego. Oznaczano zmiany ilościowe w obrębie białek rozpuszczalnych i azotu aminowego oraz pH. Stwierdzono, że największe zmiany ilościowe białek rozpuszczalnych miały miejsce w liofilizatach grasicy, a azotu aminowego w gruczole przechowywanym w -12°C. Natomiast zmiany pH we wszystkich badanych wariantach były minimalne. Największą stabilnością charakteryzował się surowiec składowany w temperaturze -30°C.The studies were undertaken to evaluate the effect of long-therm storage and methods of preservation (freezing and storage at -12 and -30°C and freeze-drying) on the suitability of bovine thymus as a raw material for the pharmaceutical industry. Quantity changes in soluble protein, amino nitrogen and pH were determined. The greatest changes in soluble protein were observed for freeze-dried samples, while for amino nitrogen for gland stored at -12°C. pH changes were insignificant in all analysed methods of storage. Investigations indicated the best stability of the gland stored at -30°C