45S rDNA Diversity as One Step towards Ribosomal Heterogeneity in .

The keystone of ribosome biogenesis is the transcription of 45S rDNA. The genome contains hundreds of 45S rDNA units; however, they are not all transcribed. Notably, 45S rDNA units contain insertions/deletions revealing the existence of heterogeneous rRNA genes and, likely, heterogeneous ribosomes for rRNAs.

A plant-like mechanism coupling m6A reading to polyadenylation safeguards transcriptome integrity and developmental gene partitioning in .

Correct 3'end processing of mRNAs is one of the regulatory cornerstones of gene expression. In a parasite that must adapt to the regulatory requirements of its multi-host life style, there is a need to adopt additional means to partition the distinct transcriptional signatures of the closely and tandemly arranged stage-specific genes. In this study, we report our findings in of an m6A-dependent 3'end polyadenylation serving as a transcriptional barrier at these .

Cereal Circular RNAs (circRNAs): An Overview of the Computational Resources for Identification and Analysis.

Circular RNAs (circRNAs) are a widespread class of endogenous noncoding RNAs and they have been studied in the past few years, implying important biological functions in all kingdoms of life. Recently, circRNAs have been identified in many plant species, including cereal crops, showing differential expression during stress response and developmental programs, which suggests their role in these process. In the following years, it is expected that insights into the functional roles of circRNAs can be used by cereal scientists and molecular breeders with the aim to develop new strategies for crop improvement.

Towards accurate infrared spectral density of weak H-bonds in absence of relaxation mechanisms.

Following the previous theoretical developments to completely reproduce the IR spectra of weak hydrogen bond complexes within the framework of the linear response theory (LRT), the quantum theory of the high stretching mode spectral density (SD) of weak H-bonds is reconsidered. Within the LRT theory, the SD is the one sided Fourier transform of the autocorrelation function (ACF) of the high stretching mode dipole moment operator. In order to provide more accurate theoretical bandshapes, we have explored the equivalence between the SDs given in previous studies with respect to a new quantum one, and revealed that in place of the basic equations used in the precedent works for which the SD I(ω)=2Re∫G(t)edt where the ACF G(t) = ⟨μ(0)μ(t)⟩ = tr {ρ {μ(0)} {μ(t)}}, one can use a new expression for the SD, given by I(ω)=2ωRe∫G(t)edt where G(t)=μ(0)μ(t)=1βtrρ∫μ(0)μ(t+iλℏ)dλ.

Equivalence between the Classical and Quantum IR Spectral Density Approaches of Weak H-Bonds in the Absence of Damping.

The aim of this paper is to overhaul the quantum elucidation of the spectral density (SD) of weak H-bonds treated without taking into account any of the damping mechanisms. The reconsideration of the SD is performed within the framework the linear response theory. Working in the setting of the strong anharmonic coupling theory and the adiabatic approximation, the simplified expression of the classical SD, in the absence of dampings, is equated to be I(ω) = Re[∫G(t)e dt] in which the classical-like autocorrelation function (ACF), G(t), is given by G(t) = tr{ρ(β){μ(0)}{μ(t)}}.

Dynamics and sources of pharmaceutically active compounds in a coastal Mediterranean river during heavy rains.

Concentrations of pharmaceutically active compounds (PACs) in freshwater systems depend on numerous factors such as land use and hydrometeorological conditions. In the Mediterranean, heavy rain events are of particular importance as they highly influence the concentration of micropollutants found in freshwater and are a source of recurrent first foul flushes due to combined sewer overflows (CSOs). In this study, we seek to assess the dynamics of pharmaceuticals during storm events in coastal Mediterranean rivers at a fine scale and to determine their contribution to multicontamination phenomena owing to CSOs.

The embryonic life history of the tropical sea hare (Gastropoda: Opisthobranchia) under ambient and elevated ocean temperatures.

Ocean warming represents a major threat to marine biota worldwide, and forecasting ecological ramifications is a high priority as atmospheric carbon dioxide (CO) emissions continue to rise. Fitness of marine species relies critically on early developmental and reproductive stages, but their sensitivity to environmental stressors may be a bottleneck in future warming oceans. The present study focuses on the tropical sea hare, (Gastropoda: Opisthobranchia), a common species found throughout the Indo-West Pacific and Atlantic Oceans.

Evidence for ARGONAUTE4-DNA interactions in RNA-directed DNA methylation in plants.

RNA polymerase V (Pol V) long noncoding RNAs (lncRNAs) have been proposed to guide ARGONAUTE4 (AGO4) to chromatin in RNA-directed DNA methylation (RdDM) in plants. Here, we provide evidence, based on laser UV-assisted zero-length cross-linking, for functionally relevant AGO4-DNA interaction at RdDM targets. We further demonstrate that Pol V lncRNAs or the act of their transcription are required to lock Pol V holoenzyme into a stable DNA-bound state that allows AGO4 recruitment via redundant glycine-tryptophan/tryptophan-glycine AGO hook motifs present on both Pol V and its associated factor, SPT5L.

Epigenetic origin of adaptive phenotypic variants in the human blood fluke Schistosoma mansoni.

Background: Adaptive evolution is not possible without the generation of phenotypic variants. The origin of these variations has been a central topic in evolutionary biology. Up to now, it was commonly accepted that standing genetic variation is the only cause of phenotypic variants.

The Western South Atlantic Ocean in a High-CO2 World: Current Measurement Capabilities and Perspectives.

An international multi-disciplinary group of 24 researchers met to discuss ocean acidification (OA) during the Brazilian OA Network/Surface Ocean-Lower Atmosphere Study (BrOA/SOLAS) Workshop. Fifteen members of the BrOA Network (www.broa.

Photolysis of tembotrione and its main by-products under extreme artificial conditions: comparison with another β-triketone herbicide.

The photolytic behaviour of tembotrione, a new chemical herbicide intended for foliar application in corn, was investigated under unnatural and extreme photochemical exposure in aqueous solutions in the laboratory. It appeared that degradation was dependent on pH and occurred more rapidly under acidic and neutral conditions, leading predominantly to the formation of a xanthenedione type compound by intramolecular cyclisation with loss of HCl. Trace amounts of benzoic acid by-products appeared also during UV-C irradiation (λ=254 nm) of the parent compound.

A comprehensive analysis of the La-motif protein superfamily.

The extremely well-conserved La motif (LAM), in synergy with the immediately following RNA recognition motif (RRM), allows direct binding of the (genuine) La autoantigen to RNA polymerase III primary transcripts. This motif is not only found on La homologs, but also on La-related proteins (LARPs) of unrelated function. LARPs are widely found amongst eukaryotes and, although poorly characterized, appear to be RNA-binding proteins fulfilling crucial cellular functions.