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Cotton (Gossypium spp.) is a vital global source of renewable fiber and ranks among the world's most important cash crops. While extensive nuclear genomic data of Gossypium has been explored, the organellar genomic resources of allotetraploid cotton, remain largely untapped at the population level. The plastid genome (plastome) is well suited for studying plant species relationships and diversity due to its nonrecombinant uniparental inheritance. Here, we conducted de novo assembly of 336 Gossypium plastomes, mainly from domesticated cultivars, and generated a pan‐plastome level resource for population structure and genetic diversity analyses. The assembled plastomes exhibited a typical quadripartite structure and varied in length from 160 103 to 160 597 bp. At the species level, seven allotetraploid species were resolved into three clades, where Gossypium tomentosum and Gossypium mustelinum formed an early diverging clade rooted by diploids, followed by splitting two sister clades of Gossypium darwinii–Gossypium barbadense and Gossypium hirsutum–Gossypium ekmanianum–Gossypium stephensii. Within the G. hirsutum clade the resolution of cultivated accessions was less polyphyletic with landrace and wild accessions than in G. barbadense suggesting some selection on plastome in the domestication of this adaptable species of cotton. The nucleotide diversity of G. hirsutum was higher than that of G. barbadense. We specifically compared the plastomes of G. hirsutum and G. barbadense to find mutational hotspots within each species as potential molecular markers. These findings contribute a valuable resource for exploring cotton evolution as well as in the breeding of new cotton cultivars and the preservation of wild and cultivated germplasm. [ABSTRACT FROM AUTHOR]

Abstract: Alloys with composition Ti(Mn1−x Al x )2 (x Al =0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.55, 0.6, and 0.67) were studied by X-ray powder diffraction (XPD), optical microscopy, electron probe microanalysis (EPMA) and electronic density functional theory. EPMA and XPD defined an extensive solid solution of up to x Al =0.64 at 900°C. Structure determination from Rietveld refinements of X-ray powder diffraction data for Ti(Mn1−x Al x )2 (0≤ x Al ≤0.60) and from single crystal X-ray counter data for x Al =0.2 revealed a C14-MgZn2-type Laves phase, where Ti atoms fully occupy the 4f sites, whereas Mn and Al atoms share the 6h and 2a sites in various ratios. By means of density functional theory, the structural stabilities and site preferences of nine ternary compositions, Ti(Mn1−x Al x )2 (x Al =0, 0.125, 0.25, 0.375, 0.500, 0.625, 0.750, 0.875, 1.00), were further calculated for a large number of structural models. The derived Al content dependent structural stabilities, lattice parameters, and site occupations as well as enthalpies of formations are in nice agreement with experimental results. Based on the calculated data, we analyzed the occupation behaviour of Al atoms substituting for Mn atoms at the 2a and 6h sites: up to concentrations x Al <0.375 Al atoms prefer the 6h sites, whereas for 0.375< x Al <0.625 Al atoms prefer the 2a sites. The calculations furthermore revealed that the Al atoms at the 6h sites exhibit a trend of getting paired. [Copyright &y& Elsevier]

Our previous study has shown heme oxygenase-1 (HO-1) protects human lens epithelial cells (LECs) against H 2 O 2 -induced oxidative stress and apoptosis. Nrf2, the major regulator of HO-1, is triggered during the mutual induction of oxidative stress and ER stress. In response to ER stress, unfolded protein response (UPR) serves as a program of transcriptional and translational regulation mechanism with PERK involved. Both Nrf2 and ATF4 are activated as the downstream effect of PERK signaling coordinating the convergence of dual stresses. However, the ways in which Nrf2 interacting with ATF4 regulates deteriorated redox state have not yet been fully explored. Here, the transfected LECs with Nrf2 overexpression illustrated enhanced resistance in morphology and viability upon H 2 O 2 treatment condition. Intracellular ROS accumulation arouses ER stress, initiating PERK dependent UPR and inducing the downstream signal Nrf2 and ATF4 auto-phosphorylation. Further, converging at target promoters, ATF4 facilitates Nrf2 with the expression of ARE-dependent phase II antioxidant and detoxification enzymes. According to either Nrf2 or ATF4 gene modification, our data suggests a novel interaction between Nrf2 and ATF4 under oxidative and ER stress, thus drives specific enzymatic and non-enzymatic reactions of antioxidant mechanisms maintaining redox homeostasis. Therapies that restoring Nrf2 or ATF4 expression might help to postpone LECs aging and age-related cataract formation. [ABSTRACT FROM AUTHOR]

• The best human STING agonist 12b displayed similar activities with 2′3′-cGAMP. • Compound 2g, 9g, and 12b can directly bind to the human STING protein. • The Structure-Activity Relationships of synthetic compounds were discussed. • Compound 12b is better than 2′3′-cGAMP in the induction of assorted cytokines. STING (Stimulator of Interferon Genes) has become a focal point in immunology research and a target in drug discovery. The discovery of a potent human-STING agonist is expected to revolutionize current anti-virus or cancer immunotherapy. Inspired by the structure and function of murine STING-specific agonists (DMXAA and CMA), we rationally designed and synthesized four series of novel compounds for the enhancement of human sensitivity. In the cell-based assay, we identified six compounds from all the synthetic small molecules: 2g, 9g, and 12b are STING agonists that are efficacious across species, and all have the skeleton of acridone; 1b, 1c, and 12c just function in the murine STING pathway. Notably, 12b exhibits the best activity among the six agonists, and its inductions of both human and murine STING-dependent signalling are similar to that of 2′3′-cGAMP, which is a well-known STING inducer. While a protein assay indicated that 2 g, 9 g, and 12b could activate the pathway by directly binding human STING, 12b also displayed the strongest binding affinity. Additionally, our studies show that 12b can induce faster, more powerful, and more durable responses of assorted cytokines in a native system than 2′3′-cGAMP. Consequently, our team is the first to successfully modify murine STING agonists to obtain human sensitivity, and these results suggest that 12b is a potent direct-human-STING agonist. Additionally, the acridone analogues demonstrate tremendous potential in the treatment of tumours or viral infections. [ABSTRACT FROM AUTHOR]