The miRNA biogenesis factors, p72/DDX17 and KHSRP regulate the protein level of Ago2 in human cells

© 2016 Elsevier B.V. MicroRNAs (miRNAs) are short (21–23 nt long) RNAs that post-transcriptionally regulate gene expression in plants and animals. They are key regulators in all biological processes. In mammalian cells miRNAs are loaded into one of the four members of the Argonaute (Ago) protein family to form the RNA-induced silencing complex (RISC). RISCs inhibit the translation of mRNAs that share sequence complementarity with their loaded miRNAs. miRNA processing and miRNA-mediated gene regulation are highly regulated processes and involve many RNA-binding proteins as auxiliary factors. Here we show that the two RNA-binding proteins, p72 and KHSRP, both with known roles in promoting miRNA biogenesis, regulate the protein level of human Ago2 in transformed human cells. We determined that p72 and KHSRP influence Ago2 stability by regulating miRNA levels in the cell and that loss of p72/KHSRP results in a decrease of unloaded Ago2

Critical Behavior of La0.8Ca0.2Mn1−xCoxO3 Perovskite (0.1 ≤ x ≤ 0.3)

The critical properties of La0.8Ca0.2Mn1−xCoxO3 (x = 0, 0.1, 0.2 and 0.3) compounds were investigated by analysis of the magnetic measurements in the vicinity of their critical temperature. Arrott plots revealed that the paramagnetic PM-ferromagnetic (FM) phase transition for the sample with x = 0 is a first order transition, while it is a second order transition for all doped compounds. The critical exponents β, γ and δ were evaluated using modified Arrott plots (MAP) and the Kouvel-Fisher method (KF). The reliability of the evaluated critical exponents was confirmed by the Widom scaling relation and the universal scaling hypothesis. The values of the critical exponents for the doped compounds were consistent with the 3D-Heisenberg model for magnetic interactions. For x = 0.1, the estimated critical components are found inconsistent with any known universality class. In addition, the local exponent n was determined from the magnetic entropy change and found to be sensitive to the magnetic field in the entire studied temperature range.This work has been supported by the Tunisian Ministry of Scientific Research and Technology and Institute Neel at Grenobl

miR-132/212 knockout mice reveal roles for these miRNAs in regulating cortical synaptic transmission and plasticity

miR-132 and miR-212 are two closely related miRNAs encoded in the same intron of a small non-coding gene, which have been suggested to play roles in both immune and neuronal function. We describe here the generation and initial characterisation of a miR-132/212 double knockout mouse. These mice were viable and fertile with no overt adverse phenotype. Analysis of innate immune responses, including TLR-induced cytokine production and IFNβ induction in response to viral infection of primary fibroblasts did not reveal any phenotype in the knockouts. In contrast, the loss of miR-132 and miR-212, while not overtly affecting neuronal morphology, did affect synaptic function. In both hippocampal and neocortical slices miR-132/212 knockout reduced basal synaptic transmission, without affecting paired-pulse facilitation. Hippocampal long-term potentiation (LTP) induced by tetanic stimulation was not affected by miR-132/212 deletion, whilst theta burst LTP was enhanced. In contrast, neocortical theta burst-induced LTP was inhibited by loss of miR-132/212. Together these results indicate that miR-132 and/or miR-212 play a significant role in synaptic function, possibly by regulating the number of postsynaptic AMPA receptors under basal conditions and during activity-dependent synaptic plasticity

Thermal expansion measurements of the quasi-one-dimensional conductor K0.30MoO3

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Thermodynamic and critical properties of the charge density wave system ErTe3

International audienceWe present specific heat and ultrasonic measurements on the rare earth tritelluride ErTe3 compound. Thermodynamic anomalies are observed at the upper charge density wave (CDW) phase transition TCDW1=265 K and the second one at TCDW2=155 K. Similar critical behaviors are found at both CDW phase transitions and that we tentatively described in terms of the 3D XY model. Different anisotropic stress dependences dTCDW1/dpi and dTCDW2/dpi are found at the two successive CDW phase transitions. Magnitude of the elastic constant anomalies at TCDW2 is ten times smaller than that at TCDW1. Anomalies in the elastic constants at the upper CDW TCDW1 exhibit two dimensional features in the layer planes while in contrast a three dimensional behavior is observed at TCDW2

Heat capacity, thermal expansion and pressure derivative of critical temperature at the superconducting and charge density wave (CDW) transitions in NbSe2

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Heat Capacity of the 1D SDW system (TMTTF)(2)Br and 2D CDW system 1T-TaS(2) in magnetic field

International audienceThe equilibrium heat capacity of the 1D system (TMTTF)(2)Br with spin density wave and the 2D system 1T-TaS(2) with charge density wave were investigated in the temperature range between 0.07K and 10K and in a magnetic field up to 10T. For both materials an additional contribution to the heat capacity was found below 1K, which is proportional to T(-2). This contribution is caused by low energy excitations with abroad spectrum of their relaxation time. The relaxation time is strongly temperature dependent and follows the Arrhenius law, i.e. the relaxation is a thermal activated process. For both materials the same absolute value of the T(-2) term and the same activation energy E(a)/k(B) = 0.5K was found. In difference to (TMTTF)(2)Br, where the heat capacity is strongly field dependent, the heat capacity of 1T-TaS(2) is constant up to 5T

Elastic anomalies at the charge density wave transition in TbTe3

International audienceThe set of elastic constants of the charge density wave (CDW) rare earth tritelluride TbTe3 has been measured at 15 MHz in the temperature range 300-360 K. Large anomalies in the velocity and ultrasonic attenuation of the longitudinal C11 and C33 modes are observed at the charge density wave phase transition TCDW = 333 K. Anisotropic stress dependence dTCDW/dp is found, the component dTCDW/dp1 and dTCDW/dp3 in the (a,c) plane are one order of magnitude larger than the component dTCDW/dp2 perpendicular to it. The Landau theory has been used to explain the explain the experimental data.Critical behavior near the charge density wave phase transition is described in terms of a phenomenological dynamic scaling theory

On the low vibrational states seen in the heat capacity of incommensurate ThBr4

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