Biochemistry

Comprehensive polyphenol profiling of a strawberry extract (Fragaria × ananassa) by ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry

The aim of metabolic untargeted profiling is to detect and identify unknown compounds in a biological matrix to achieve the most comprehensive metabolic coverage. In phytochemical mixtures, however, the complexity of the sample could present significant difficulties in compound identification. In this case, the optimization of both the chromatographic and the mass-spectrometric conditions is supposed to be crucial for the detection and identification of the largest number of compounds.

Sensitivity to heavy-metal ions of unfolded fullerene quantum dots

A novel type of graphene-like quantum dots, synthesized by oxidation and cage-opening of C60 buckminsterfullerene, has been studied as a ?uorescent and absorptive probe for heavy-metal ions. The lattice structure of such unfolded fullerene quantum dots (UFQDs) is distinct from that of graphene since it includes both carbon hexagons and pentagons. The basic optical properties, however, are similar to those of regular graphene oxide quantum dots.

Gcn5 histone acetyltransferase is present in the mitoplasts

In Saccharomyces cerevisiae the Lysine-acetyltransferase Gcn5 (KAT2) is part of the SAGA complex and is responsible for histone acetylation widely or at specific lysines. In this paper we report that GCN5 deletion differently affects the growth of two strains. The defective mitochondrial phenotype is related to a marked decrease in mtDNA content, which also involves the deletion of specific regions of the molecule.

Acidic cell elongation drives cell differentiation in the Arabidopsis root

In multicellular systems, the control of cell size is fundamental in regulating the development and growth of the different organs and of the whole organism. In most systems, major changes in cell size can be observed during differentiation processes where cells change their volume to adapt their shape to their final function. How relevant changes in cell volume are in driving the differentiation program is a long-standing fundamental question in developmental biology.

Building the differences: A case for the ground tissue patterning in plants

A key question in biology is to understand how interspecies morphological diversities originate. Plant roots present a huge interspecific phenotypical variability, mostly because roots largely contribute to adaptation to different kinds of soils. One example is the interspecific cortex layer number variability, spanning from one to several.

Deficiency in the nuclear long noncoding RNACharme causes myogenic defects and heart remodeling in mice

Myogenesis is a highly regulated process that involves the conversion of progenitor cells into multinucleated myofibers. Besides proteins and miRNAs, long noncoding RNAs (lncRNAs) have been shown to participate in myogenic regulatory circuitries. Here, we characterize a murine chromatin-associated muscle-specific lncRNA, Charme, which contributes to the robustness of the myogenic program in vitro and in vivo. In myocytes, Charme depletion triggers the disassembly of a specific chromosomal domain and the downregulation of myogenic genes contained therein.

The ever-evolving concept of the gene: The use of RNA/Protein experimental techniques to understand genome functions

The completion of the human genome sequence together with advances in sequencing technologies have shifted the paradigm of the genome, as composed of discrete and hereditable coding entities, and have shown the abundance of functional noncoding DNA. This part of the genome, previously dismissed as "junk" DNA, increases proportionally with organismal complexity and contributes to gene regulation beyond the boundaries of known protein-coding genes. Different classes of functionally relevant nonprotein-coding RNAs are transcribed from noncoding DNA sequences.

FUS affects circular RNA expression in murine embryonic stem cell-derived motor neurons

The RNA-binding protein FUS participates in several RNA biosynthetic processes and has
been linked to the pathogenesis of amyotrophic lateral sclerosis (ALS) and frontotemporal
dementia. Here we report that FUS controls back-splicing reactions leading to circular RNA
(circRNA) production. We identified circRNAs expressed in
in vitro
-derived mouse motor
neurons (MNs) and determined that the production of a considerable number of these
circRNAs is regulated by FUS. Using RNAi and overexpression of wild-type and ALS-asso-

Climate change promotes hybridisation between deeply divergent species

Rare hybridisations between deeply divergent animal species have been reported for decades in a wide range of taxa, but have often remained unexplained, mainly considered chance events and reported as anecdotal. Here, we combine field observations with long-term data concerning natural hybridisations, climate, land-use, and field-validated species distribution models for two deeply divergent and naturally sympatric toad species in Europe (Bufo bufo and Bufotes viridis species groups).

Cadherin-7 enhances Sonic Hedgehog signalling by preventing Gli3 repressor formation during neural tube patterning

Sonic Hedgehog (Shh) is a ventrally enriched morphogen controlling dorsoventral patterning of the neural tube. In the dorsal spinal cord, Gli3 protein bound to suppressor-of-fused (Sufu) is converted into Gli3 repressor (Gli3R), which inhibits Shh-target genes. Activation of Shh signalling prevents Gli3R formation, promoting neural tube ventralization. We show that cadherin-7 (Cdh7) expression in the intermediate spinal cord region is required to delimit the boundary between the ventral and the dorsal spinal cord.

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