Genome sequence of M6, a diploid inbred clone of the high‐glycoalkaloid‐producing tuber‐bearing potato species Solanum chacoense,reveals residual heterozygosity

Cultivated potato (Solanum tuberosum L.) is a highly heterozygous autotetraploid that presents challenges in genome analyses and breeding. Wild potato species serve as a resource for the introgression of important agronomic traits into cultivated potato. One key species is Solanum chacoense and the diploid, inbred clone M6, which is self‐compatible and has desirable tuber market quality and disease resistance traits. Sequencing and assembly of the genome of the M6 clone of S. chacoense generated an assembly of 825 767 562 bp in 8260 scaffolds with an N50 scaffold size of 713 602 bp. Pseudomolecule construction anchored 508 Mb of the genome assembly into 12 chromosomes. Genome annotation yielded 49 124 high‐confidence gene models representing 37 740 genes. Comparative analyses of the M6 genome with six other Solanaceae species revealed a core set of 158 367 Solanaceae genes and 1897 genes unique to three potato species. Analysis of single nucleotide polymorphisms across the M6 genome revealed enhanced residual heterozygosity on chromosomes 4, 8 and 9 relative to the other chromosomes. Access to the M6 genome provides a resource for identification of key genes for important agronomic traits and aids in genome‐enabled development of inbred diploid potatoes with the potential to accelerate potato breeding.     

The Geomagnetic Field Is a Compass Cue in Cataglyphis Ant Navigation

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Glycosylation controls sodium-calcium exchanger 3 sub-cellular localization during cell cycle

The Na⁺/Ca²⁺ exchanger (NCX) is a membrane antiporter that has been identified in the plasma membrane, the inner membrane of the nuclear envelope and in the membrane of the endoplasmic reticulum (ER). In humans, three genes have been identified, encoding unique NCX proteins. Although extensively studied, the NCX’s sub-cellular localization and mechanisms regulating the activity of different subtypes are still ambiguous. Here we investigated the subcellular localization of the NCX subtype 3 (NCX3) and its impact on the cell cycle. Two phenotypes, switching from one to the other during the cell cycle, were detected. One phenotype was NCX3 in the plasma membrane during S and M phase, and the other was NCX3 in the ER membrane during resting and interphase. Glycosylation of NCX3 at the N45 site was required for targeting the protein to the plasma membrane, and the N45 site functioned as an on-off switch for the translocation of NCX3 to either the plasma membrane or the membrane of the ER. Introduction of an N-glycosylation deficient NCX3 mutant led to an arrest of cells in the G0/G1 phase of the cell cycle. This was accompanied by accumulation of de-glycosylated NCX3 in the cytosol (that is in the ER), where it transported calcium ions (Ca²⁺) from the cytosol to the ER. These results, obtained in transfected HEK293T and HeLa and confirmed endogenously in SH-SY5Y cells, suggest that cells can use a dynamic Ca²⁺ signaling toolkit in which the NCX3 sub-cellular localization changes in synchrony with the cell cycle.     

Carrier Transport and Recombination in Efficient “All‐Small‐Molecule” Solar Cells with the Nonfullerene Acceptor IDTBR

Reaching device efficiencies that can rival those of polymer‐fullerene Bulk Heterojunction (BHJ) solar cells (>10%) remains challenging with the “All‐Small‐Molecule” (All‐SM) approach, in part because of (i) the morphological limitations that prevail in the absence of polymer and (ii) the difficulty to raise and balance out carrier mobilities across the active layer. In this report, the authors show that blends of the SM donor DR3TBDTT (DR3) and the nonfullerene SM acceptor O‐IDTBR are conducive to “All‐SM” BHJ solar cells with high open‐circuit voltages (V_OC) >1.1 V and PCEs as high as 6.4% (avg. 6.1%) when the active layers are subjected to a post‐processing solvent vapor‐annealing (SVA) step with dimethyl disulfide (DMDS). Combining electron energy loss spectroscopy (EELS) analyses and systematic carrier recombination examinations, the authors show that SVA treatments with DMDS play a determining role in improving charge transport and reducing non‐geminate recombination for the DR3:O‐IDTBR system. Correlating the experimental results and device simulations, it is found that substantially higher BHJ solar cell efficiencies of >12% can be achieved if the IQE and carrier mobilities of the active layer are increased to >85% and >10^?4 cm² V^?1 s^?1, respectively, while suppressing the recombination rate constant k to <10^?12 cm³ s^?1.     

Water quality parameters and tipping points of dragonfly diversity and abundance in fishponds

Fishponds are often enriched with nutrients in order to increase phytoplankton and zooplankton populations to support fish production. This eutrophication often leads to a global decrease of biodiversity. This biodiversity shift may be identified by a tipping point, the value of an environmental parameter above which a significant change of species richness and abundance occurs. A total of 110 eutrophic to highly eutrophic fishponds were studied in two areas in France to investigate parameters governing dragonfly species richness and species abundance by determining tipping points. Parameters investigated were chlorophyll a (CHL), water transparency, total N (TN), total P (TP), aquatic plant richness and coverage, adult dragonfly richness and abundance, and fish harvest. A high species richness of dragonflies was found in fishponds, with a total of 34 species, including six species of conservation concern. Dragonfly richness and abundance was shown to be negatively influenced by higher degrees of eutrophication. A high diversity of dragonflies occurred in the fishponds with CHL concentrations below 127 µg/l, water transparency above 67 cm, TN concentrations below 2.30 mg/l, and a fish harvest smaller than 253 kg/ha. A minimum of 5% of aquatic plant cover and the presence of a minimum 9 aquatic plant species seem to promote the richness and abundance of dragonflies. According to tipping points, 19 dragonfly species could be determined as indicator species for water quality in fishponds.     

Reconstituting Corticostriatal Network on-a-Chip Reveals the Contribution of the Presynaptic Compartment to Huntington’s Disease

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NF-κB-Chromatin Interactions Drive Diverse Phenotypes by Modulating Transcriptional Noise

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Regenerating Eye Tissues to Preserve and Restore Vision

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