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Key message Twelve potato accessions were selected to represent two principal views on potato taxonomy. The genomes were sequenced and analyzed for structural variation (copy number variation) against three published potato genomes. Abstract The common potato (Solanum tuberosum L.) is an important staple crop with a highly heterozygous and complex tetraploid genome. The other taxa of cultivated potato contain varying ploidy levels (2X–5X), and structural variations are common in the genomes of these species, likely contributing to the diversification or agronomic traits during domestication. Increased understanding of the genomes and genomic variation will aid in the exploration of novel agronomic traits. Thus, sequencing data from twelve potato landraces, representing the four ploidy levels, were used to identify structural genomic variation compared to the two currently available reference genomes, a double monoploid potato genome and a diploid inbred clone of S. chacoense. The results of a copy number variation analysis showed that in the majority of the genomes, while the number of deletions is greater than the number of duplications, the number of duplicated genes is greater than the number of deleted ones. Specific regions in the twelve potato genomes have a high density of CNV events. Further, the auxin-induced SAUR genes (involved in abiotic stress), disease resistance genes and the 2-oxoglutarate/Fe(II)-dependent oxygenase superfamily proteins, among others, had increased copy numbers in these sequenced genomes relative to the references.

International audience; Purpose: To demonstrate the effectiveness of combining retinal phenotyping and focused variant filtering from genome sequencing (GS) in identifying deep intronic disease causing variants in inherited retinal dystrophies.Methods: Affected members from three pedigrees with classical enhanced S-cone syndrome (ESCS; Pedigree 1), congenital stationary night blindness (CSNB; Pedigree 2), and achromatopsia (ACHM; Pedigree 3), respectively, underwent detailed ophthalmologic evaluation, optical coherence tomography, and electroretinography. The probands underwent panel-based genetic testing followed by GS analysis. Minigene constructs (NR2E3, GPR179 and CNGB3) and patient-derived cDNA experiments (NR2E3 and GPR179) were performed to assess the functional effect of the deep intronic variants.Results: The electrophysiological findings confirmed the clinical diagnosis of ESCS, CSNB, and ACHM in the respective pedigrees. Panel-based testing revealed heterozygous pathogenic variants in NR2E3 (NM_014249.3; c.119-2A>C; Pedigree 1) and CNGB3 (NM_019098.4; c.1148delC/p.Thr383Ilefs*13; Pedigree 3). The GS revealed heterozygous deep intronic variants in Pedigrees 1 (NR2E3; c.1100+1124G>A) and 3 (CNGB3; c.852+4751A>T), and a homozygous GPR179 variant in Pedigree 2 (NM_001004334.3; c.903+343G>A). The identified variants segregated with the phenotype in all pedigrees. All deep intronic variants were predicted to generate a splice acceptor gain causing aberrant exonization in NR2E3 [89 base pairs (bp)], GPR179 (197 bp), and CNGB3 (73 bp); splicing defects were validated through patient-derived cDNA experiments and/or minigene constructs and rescued by antisense oligonucleotide treatment.Conclusions: Deep intronic mutations contribute to missing heritability in retinal dystrophies. Combining results from phenotype-directed gene panel testing, GS, and in silico splice prediction tools can help identify these difficult-to-detect pathogenic deep intronic variants.

The direct assembly of benzo[c]carbazole derivatives via the Diels-Alder reaction of arynes and easily accessible 2-alkenylidoles was reported. By employing different aryne precursor loads, 6,7-dihydrobenzo[c]carbazoles or aryl-substituted 7,11b-dihydrobenzo[c]carbazoles could be controllably generated in good to excellent yields under a nitrogen atmosphere. On the other hand, when the reaction was conducted under oxygen, oxidated/aromatized product benzo[c]carbazoles could be generated directly with high selectivity and efficiency in a one-step manner. Interestingly, the benzo[c]carbazole-5-carboxamide amidation derivatives of the above products showed good antitumor activities. The inhibitory effect of these molecules against cancer cells was also described.

A concise and direct synthetic strategy for the construction of benzo[a]carbazole-5-carboxylates has been disclosed via the Diels–Alder reaction of arynes and 3-alkenylindoles. The reaction is highly selective and affords the benzo[a]carbazole-5-carboxylates in good-to-excellent yields.

Pd-catalyzed annulation of aryne and aryl ketone O-acetyloxime via C–H bond activation was realized. Through the C–H bond activation/insertion/cyclization/elimination reaction sequence, phenanthridines are successfully constructed, providing an attractive strategy to approach substituted heterocycle without preactivation of starting materials.

Dielectric spectroscopy was used in a frequency-dependent study of pristine nematic liquid crystals (E7) and E7 doped with multi-walled carbon nanotubes. The experiment was carried out in the frequency range of 10–1–105 Hz and temperature range of 303–353 K. The low-frequency (1–102 Hz) data reflect the electrode polarization due to space-charge polarization dictated by both the concentration and diffusion constant of impurity ions and, thus, are particularly useful for interpretation of the dopant effect on the ion transport. It was found that the activation energy for ionic diffusion is slightly higher and the diffusion constant significantly smaller in the suspensions.

The dielectric relaxation dynamics of a dual-frequency liquid crystal-dye composite were studied and the effect of the photoinduced isomerization of the azo dye on the dielectric spectrum of the cell under illumination by an argon-ion laser operating at wavelength of 514.5 nm and irradiance of 550 mW cm−2. It was found that the illumination process has a profound influence on the dielectric spectrum of the dye-doped dual-frequency liquid crystal in the low-frequency range.

Background Bardet‐Biedl syndrome (BBS) is an autosomal recessive pleiotropic disorder of the primary cilia that leads to severe visual loss in the teenage years. Approximately 80% of BBS cases are explained by mutations in one of the 21 identified genes. Documented causative mutation types include missense, nonsense, copy number variation (CNV), frameshift deletions or insertions, and splicing variants. Methods Whole genome sequencing was performed on a patient affected with BBS for whom no mutations were identified using clinically approved genetic testing of the known genes. Analysis of the WGS was done using internal protocols and publicly available algorithms. The phenotype was defined by retrospective chart review. Results We document a female affected with BBS carrying the most common BBS1 mutation (BBS1: Met390Arg) on the maternal allele and an insertion of a ~1.7‐kb retrotransposon in exon 13 on the paternal allele. This retrotransposon insertion was not automatically annotated by the standard variant calling protocols used. This novel variant was identified by visual inspection of the alignment file followed by specific genome analysis with an available algorithm for transposable elements. Conclusion This report documents a novel mutation type associated with BBS and highlights the importance of systematically performing transposon detection analysis on WGS data of unsolved cases.

The direct assembly of benzo[c]carbazole derivatives via the Diels–Alder reaction of arynes and easily accessible 2-alkenylidoles was reported. By employing different aryne precursor loads, 6,7-dihydrobenzo[c]carbazoles or aryl-substituted 7,11b-dihydrobenzo[c]carbazoles could be controllably generated in good to excellent yields under a nitrogen atmosphere. On the other hand, when the reaction was conducted under oxygen, oxidated/aromatized product benzo[c]carbazoles could be generated directly with high selectivity and efficiency in a one-step manner. Interestingly, the benzo[c]carbazole-5-carboxamide amidation derivatives of the above products showed good antitumor activities. The inhibitory effect of these molecules against cancer cells was also described.

A concise and direct synthetic strategy for the construction of benzo[a]carbazole-5-carboxylates has been disclosed via the Diels–Alder reaction of arynes and 3-alkenylindoles. The reaction is highly selective and affords the benzo[a]carbazole-5-carboxylates in good-to-excellent yields.

Depending on the fluorinating reagent the reaction of arynes with aziridines affords fluorinated β-amino acid esters or unexpected spiro-derivatives.

Phenanthridines are prepared from various O-acetyloximes and in situ generated arynes through a C-H bond activation/insertion/cyclization/elimination sequence.

A fast-switching bistable optical intensity modulator is demonstrated. Using a dual-frequency cholesteric liquid crystal, the direct switching is achieved from the scattering focal conic state to the transparent long-pitch planar state. In comparison with the bistable cholesteric devices proposed previously, our device, characterized by its capability of direct two-way transitions between the two bistable states, possesses a very short transition time from the focal conic state to the planar state as short as 10 ms. No voltage has to be applied to sustain the optical states, making the device low energy consuming. Potential applications of this device are addressed.

This study uses the time-evolved voltage holding ratio (VHR) to measure the influence of UV exposure on a nematic liquid-crystal cell. Apart from the real-time measurement during the exposure, the time-dependent recovery of VHR is also monitored after a certain amount of UV irradiation. Our experimental results show that the cell impregnated with an adequate content of the anatase TiO 2 as a nano-additive possesses a higher VHR, which unambiguously implies that the TiO 2 nanoparticles are capable of preventing the serious ion effect caused by the harmful UV. Achieving the "green" concept, this research suggests a new approach to reduce the ion effect and extend the life of LCD devices under sunlight.

This study focuses on the electrical characteristics of nematic liquid crystals doped with anatase titania nanoparticles (NPs). Low-frequency dielectric spectroscopy between 10−2 and 103 Hz is used to investigate the space-charge polarization. The results indicate that the doped samples have lower ionic concentration, diffusion constant and activation energy due to the effect of the dopant on ion transport. Temperature-dependent data provide an insight into the feasibility of using these NPs as a dopant to promote the device performance in a real environment. Verified by the voltage holding ratio, it is clear that doping anatase NPs into liquid crystals is a potentially cost-effective and easy way to improve the device performance.