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Transcription factors (TFs) bind DNA in a sequence-specific manner and are generally cell type-specific factors and/or developmental master regulators. In contrast, general TFs (GTFs) are part of very large protein complexes and serve for RNA polymerases' recruitment to promoter sequences, generally in a cell type-independent manner. Whereas, several TFs have been proven to serve as anchors for the 3D genome organization, the role of GTFs in genome architecture have not been carefully explored. Here, we used ChIP-seq and Hi-C data to depict the role of TFIIIC, one of the RNA polymerase III GTFs, in 3D genome organization. We find that TFIIIC genome occupancy mainly occurs at specific regions, which largely correspond to Alu elements; other characteristic classes of repetitive elements (REs) such as MIR, FLAM-C and ALR/alpha are also found depending on the cell's developmental origin. The analysis also shows that TFIIIC-enriched regions are involved in cell type-specific DNA looping, which does not depend on colocalization with the master architectural protein CTCF. This work extends previous knowledge on the role of TFIIIC as a bona fide genome organizer whose action participates in cell type-dependent 3D genome looping via binding to REs. This work was supported by Bando Galileo 2022 (G22-142) to R.F. and M.T. This work was also supported by the Spanish Ministry of Science and Innovation (PID2019-107185GB-I00) and Secretaria d’Universitats i Recerca del Departament d’Empresa i Coneixement de la Generalitat de Catalunya (2017SGR1163) to S.L. The CRG acknowledge the support of the Spanish Ministry of Science and Innovation to the EMBL partnership, the Centro de Excelencia Severo Ochoa and the support of the CERCA Programme/Generalitat de Catalunya

Acetylation; Neurogenesis Acetilación; Neurogénesis Acetilació; Neurogènesi Regulation of histone acetylation dictates patterns of gene expression and hence cell identity. Due to their clinical relevance in cancer biology, understanding how human embryonic stem cells (hESCs) regulate their genomic patterns of histone acetylation is critical, but it remains largely to be investigated. Here, we provide evidence that acetylation of histone H3 lysine-18 (H3K18ac) and lysine-27 (H3K27ac) is only partially established by p300 in stem cells, while it represents the main histone acetyltransferase (HAT) for these marks in somatic cells. Our analysis reveals that whereas p300 marginally associated with H3K18ac and H3K27ac in hESCs, it largely overlapped with these histone marks upon differentiation. Interestingly, we show that H3K18ac is found at “stemness” genes enriched in RNA polymerase III transcription factor C (TFIIIC) in hESCs, whilst lacking p300. Moreover, TFIIIC was also found in the vicinity of genes involved in neuronal biology, although devoid of H3K18ac. Our data suggest a more complex pattern of HATs responsible for histone acetylations in hESCs than previously considered, suggesting a putative role for H3K18ac and TFIIIC in regulating “stemness” genes as well as genes associated with neuronal differentiation of hESCs. The results break ground for possible new paradigms for genome acetylation in hESCs that could lead to new avenues for therapeutic intervention in cancer and developmental diseases. This work was supported by Bando Galileo 2022 (G22-142) to R.F. and M.T. The research is also supported by the AIRC IG Grant 27712-A to R.F. This work was also supported by the Spanish Ministry of Science and Innovation (PID2019-107185GB-I00) to S.d.l.L. The CRG acknowledge the support of the Spanish Ministry of Science and Innovation to the EMBL partnership, the Centro de Excelencia Severo Ochoa and the support of the CERCA Programme/Generalitat de Catalunya. This work was also supported by the Ligue Contre le Cancer, committees des Landes et de la Dordogne to M.T.

We developed a sensor array made up of metal oxide thin films for the detection of stress molecules produced by plants in greenhouses for manned long term space missions. This sensor array was coupled with other sensors for illumination, CO2 and humidity to realize an advanced hybrid electronic nose that was successfully employed to monitor plant growth inside a greenhouse. The electronic nose was able to detect the onset of abiotic and biotic plant stresses. Volatile organic compounds (VOCs) emission by plants was also evaluated by head space analysis performed by gas chromatography–mass spectroscopy (GC–MS). The humidity sensor has been used also to reduce the always present effect of humidity on the metal oxide thin films. A simple correlation analysis divides the metal oxide sensors in two classes of similar characteristics, which could permit to make use of just two sensors.

We have studied the ground-state properties of boron-related dia- and paramagnetic point defects in B-doped silica. Hartree-Fock and density functional theory calculations have been performed to determine the structure, charge, and spin distribution of the boron oxygen hole center (BOHC). The currently accepted model of the BOHC is that of a hole localized on a nonbonding $2p$ orbital of an O atom in a bridge position between a B and a Si atom, $\ensuremath{\equiv}{\mathrm{B}\mathrm{---}\mathrm{O}}^{\mathbf{\ensuremath{\cdot}}}---\mathrm{Si}\ensuremath{\equiv}.$ Our calculations do not support this model and show that the structure is not stable and spontaneously evolves into a planar trigonal diamagnetic boron center, $g\mathrm{B}---,$ and a nonbridging oxygen, $\ensuremath{\equiv}{\mathrm{Si}\mathrm{---}\mathrm{O}}^{\mathbf{\ensuremath{\cdot}}}.$ The results of this study suggest that the BOHC consists of a three-coordinated B atom bound to a non bridging oxygen, $g\mathrm{B}---{\mathrm{O}}^{\mathbf{\ensuremath{\cdot}}}.$ The computed hyperfine coupling constants for this model are in quantitative agreement with those measured experimentally for B-doped silica. This assignment is consistent with recent magnetic resonance studies on borosilicates and alkali borate glasses.