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Summary: Carotenoids are indispensable to plants and critical components of the human diet. The carotenoid metabolic pathway is conserved across plant species, but our understanding of the genetic basis of carotenoid variation remains limited for the seeds of most cereal crops. To address this issue, we systematically performed linkage and association mapping for eight carotenoid traits using six recombinant inbred line (RIL) populations. Single linkage mapping (SLM) and joint linkage mapping (JLM) identified 77 unique additive QTLs and 104 pairs of epistatic QTLs. Among these QTLs, we identified 22 overlapping hotspots of additive and epistatic loci, highlighting the important contributions of some QTLs to carotenoid levels through additive or epistatic mechanisms. A genome‐wide association study based on all RILs detected 244 candidate genes significantly associated with carotenoid traits, 23 of which were annotated as carotenoid pathway genes. Effect comparisons suggested that a small number of loci linked to pathway genes have substantial effects on carotenoid variation in our tested populations, but many loci not associated with pathway genes also make important contributions to carotenoid variation. We identified ZmPTOX as the causal gene for a QTL hotspot (Q10/JLM10/GWAS019); this gene encodes a putative plastid terminal oxidase that produces plastoquinone‐9 used by two enzymes in the carotenoid pathway. Natural variants in the promoter and second exon of ZmPTOX were found to alter carotenoid levels. This comprehensive assessment of the genetic mechanisms underlying carotenoid variation establishes a foundation for rewiring carotenoid metabolism and accumulation for efficient carotenoid biofortification. [ABSTRACT FROM AUTHOR]

AIM: To investigate the protective effect of total flavonoids from Patrina villosa Juss (PJF) on the lung in an experimental rat model of acute lung injury (ALI), and to elucidate the potential mechanism. METHODS: The ALI rat model was established by instilling 5 mg/kg of lipopolysaccharide (LPS) into the airway. Sixty male SD rats were randomly divided into 4 groups: control, LPS, LPS+low-dose PJF (receiving 100 mg/kg PJF one hour before ALI modeling) and LPS+high-dose PJF (receiving 300 mg/kg PJF one hour before ALI modeling). Each group consisted of 15 animals. Lung tissues and bronchoalveolar lavage fluid (BALF) were collected from all groups 24 h after modeling. For assessment of lung tissue morphology, HE staining was performed. The wet/dry weight ratio of the lung tissue was determined using the wet/dry weighing method. Evans blue staining was conducted to assess epithelial barrier permeability in lung tissues. ELISA was used to detect the levels of inflammatory factors tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and IL-6 in the BALF, as well as oxidative stress markers including superoxide dismutase (SOD), myeloperoxi-dase (MPO) and glutathione peroxidase (GSH-Px) activity, and malondialdehyde (MDA) content in the lung tissue. The expression levels of C/EBP homologous protein (CHOP), glucose-regulated protein 78 (GRP78) and X-box binding protein 1 (XBP1) in the lung tissue were analyzed by Western blotting. RESULTS: Compared with control group, the rats in LPS group exhibited a blurred alveolar structure with a significant infiltration of inflammatory cells. The ALI score and the wet/dry weight ratio of the lung tissue were increased (P<0. 05). Concurrently, the levels of IL-6, IL-1β and TNF-α in the BALF, along with MDA content and MPO activity in the lung tissue, were elevated (P<0. 05). Additionally, the protein levels of CHOP, GRP78 and XBP1 were up-regulated in the lung tissue (P<0. 05), while the SOD and GSH-Px activity was significantly decreased (P<0. 05). Compared with LPS group, PJF intervention exerted beneficial effects on the lung tissue morphology with reduced ALI score and lower lung wet/dry weight ratio (P<0. 05). Moreover, the levels of IL-6, IL-1β and TNF-α in BALF, as well as MDA content, MPO activity and the protein levels of CHOP, GRP78 and XBP1 in the lung tissue were all significantly decreased (P<0. 05), while the SOD and GSH-Px activity was significantly increased (P<0. 05). The efficacy in high-dose group exceeded that in low-dose group. CONCLUSION: The PJF have protective effect on the lungs of rats with ALI, and its mechanism may be related to the inhibition of inflammation, oxidative stress and endoplasmic reticulum stress. [ABSTRACT FROM AUTHOR]

This article presents a multimodal genre analysis of crowdfunding proposals, an emerging web-based genre for raising funds from internet crowds for a project or venture. Based on an analysis of nine most-funded Kickstarter crowdfunding proposals, the authors describe the generic move structure using a semiotic approach and examine the role of visual images in constructing meaning within and across moves. The analysis shows that visual images facilitate potential backers' sense-making in basically two dimensions: rhetorically, functioning to persuade by establishing ethos, logos, and pathos, and compositionally, helping achieve cohesion within and between moves and facilitate move mixing, embedding, and positioning. This study also attests a case-based approach to examining multiple influences on genre emergence. [ABSTRACT FROM AUTHOR]

Summary: The nutritional traits of maize kernels are important for human and animal nutrition, and these traits have undergone selection to meet the diverse nutritional needs of humans. However, our knowledge of the genetic basis of selecting for kernel nutritional traits is limited. Here, we identified both single and epistatic quantitative trait loci (QTLs) that contributed to the differences of oil and carotenoid traits between maize and teosinte. Over half of teosinte alleles of single QTLs increased the values of the detected oil and carotenoid traits. Based on the pleiotropism or linkage information of the identified single QTLs, we constructed a trait–locus network to help clarify the genetic basis of correlations among oil and carotenoid traits. Furthermore, the selection features and evolutionary trajectories of the genes or loci underlying variations in oil and carotenoid traits revealed that these nutritional traits produced diverse selection events during maize domestication and improvement. To illustrate more, a mutator distance–relative transposable element (TE) in intron 1 of DXS2, which encoded a rate‐limiting enzyme in the methylerythritol phosphate pathway, was identified to increase carotenoid biosynthesis by enhancing DXS2 expression. This TE occurs in the grass teosinte, and has been found to have undergone selection during maize domestication and improvement, and is almost fixed in yellow maize. Our findings not only provide important insights into evolutionary changes in nutritional traits, but also highlight the feasibility of reintroducing back into commercial agricultural germplasm those nutritionally important genes hidden in wild relatives. Significance Statement: The identification and selection‐feature characterization of genetic loci contributing to nutritional trait variation between maize and teosinte is of fundamental importance in understanding the evolutionary interface between plant and human. Most favorable alleles associated with nutritional traits exist in teosinte and are not fixed in modern maize, underscoring the potential benefit of introducing teosinte alleles during maize breeding regimens to yield hybrids with desirable nutritional traits. [ABSTRACT FROM AUTHOR]