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1.
BMC Plant Biol ; 21(1): 45, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33451287

RESUMO

BACKGROUND: 'Regal Splendour' (Hosta variety) is famous for its multi-color leaves, which are useful resources for exploring chloroplast development and color changes. The expressions of chlorophyll biosynthesis-related genes (HrHEMA, HrPOR and HrCAO) in Hosta have been demonstrated to be associated with leaf color. Herein, we isolated, sequenced, and analyzed HrHEMA, HrPOR and HrCAO genes. Subcellular localization was also performed to determine the location of the corresponding enzymes. After plasmid construction, virus-induced gene silencing (VIGS) was carried out to reduce the expressions of those genes. In addition, HrHEMA-, HrPOR- and HrCAO-overexpressing tobacco plants were made to verify the genes function. Changes of transgenic tobacco were recorded under 2000 lx, 6000 lx and 10,000 lx light intensity. Additionally, the contents of enzyme 5-aminolevulinic acid (5-ALA), porphobilinogen (PBG), chlorophyll a and b (Chla and Chlb), carotenoid (Cxc), superoxide dismutase (SOD), peroxidase (POD), malondialdehyde (MDA), proline (Pro) and catalase (CAT) under different light intensities were evaluated. RESULTS: The silencing of HrHEMA, HrPOR and HrCAO genes can induce leaf yellowing and chloroplast structure changes in Hosta. Specifically, leaves of Hosta with HrCAO silencing were the most affected, while those with HrPOR silencing were the least affected. Moreover, all three genes in tobacco were highly expressed, whereas no expression was detected in wild-type (WT). However, the sensitivities of the three genes to different light intensities were different. The highest expression level of HrHEMA and HrPOR was detected under 10,000 lx of illumination, while HrCAO showed the highest expression level under 6000 lx. Lastly, the 5-ALA, Chla, Cxc, SOD, POD, MDA, Pro and CAT contents in different transgenic tobaccos changed significantly under different light intensities. CONCLUSION: The overexpression of these three genes in tobacco enhanced photosynthesis by accumulating chlorophyll content, but the influential level varied under different light intensities. Furthermore, HrHEMA-, HrPOR- and HrCAO- overexpressing in tobacco can enhance the antioxidant capacity of plants to cope with stress under higher light intensity. However, under lower light intensity, the antioxidant capacity was declined in HrHEMA-, HrPOR- and HrCAO- overexpressing tobaccos.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33090014

RESUMO

Interleukin-22 (IL-22) is identified as a tumor-promoting factor in certain cancers, which was secreted by tumor infiltrated lymphocytes. However, the role of IL-22 in breast cancer remains conflicting. In this study, we assessed the expression of IL-22, IL-22 receptor 1 (IL-22R1), CD4, CD8, FOXP3, and CD68 in breast cancer by immunohistochemistry. IL-22 expression was exhibited in 105 (69.1%) cases in tumor cells (tIL-22), whereas only 24 (15.8%) samples displayed IL-22 expression in stromal cells. Multivariate analysis showed that tIL-22 expression was a poor prognostic factor for overall survival (OS) (p = 0.04). Meanwhile, IL-22R1 was predominantly presented in tumor cells (84.9%), which was associated with tIL-22 expression. The CD68-positive tumor-associated macrophages (TAMs) displayed the highest infiltration rate (50.7%) compared with CD4-, CD8-, and FOXP3-positive cells. Kaplan-Meier analysis confirmed patients with high TAM infiltration displayed significantly worse relapse-free survival (RFS) compared with low TAMs group (p = 0.017). TAM infiltration was also positively associated with tIL-22 and IL-22R1 expression. Furthermore, tIL-22 expression together with high TAM infiltration displayed the worst prognosis outcomes both in OS (p = 0.039) and RFS (p = 0.008). Instead of lymphocytes, our data indicated that tumor cells express IL-22 in breast cancer that is associated with IL-22R1, high TAM infiltrating, and poor prognosis.

3.
Chin J Nat Med ; 18(9): 684-695, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32928512

RESUMO

Schisandra chinensis Turcz. (Baill.) is a plant species with fruits that have been well known in Far Eastern medicine for a long time. It has traditionally been used as a stimulating and fortifying agent in cases of physical exhaustion and to inhibit fatigue. The major bioactive compounds found in S. chinensis are lignans with a dibenzocyclooctadiene skeleton, but little is known about their biosynthesis in plants. S. chinensis is the ideal medicinal plant for studying the biosynthesis of lignans, especially the dibenzocyclooctadiene skeleton. Genomic information for this important herbal plant is unavailable. To better understand the lignan biosynthesis pathway, we generated transcriptome sequences from the fruit during ripening and performed de novo sequence assembly, yielding 136 843 unique transcripts with N50 of 1778 bp. Putative functions could be assigned to 41 824 transcripts (51.57%) based on BLAST searches against annotation databases including GO (Gene ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes). Furthermore, 22 candidate cytochrome P450 genes and 15 candidate dirigent proteins genes that were most likely involved in the lignan biosynthesis pathway were discovered based on transcriptome sequencing of S. chinensis. The genomic data obtained from S. chinensis, especially the identification of putative genes involved in the lignan biosynthesis pathway, will facilitate our understanding of lignan biosynthesis at the molecular level. The lignan metabolite profiles were analyzed by metabolomes, the accumulation patterns of 30 metabolites involved in the lignan pathway were studied. Co-expression network of lignan contents and transcriptional changes showed 355 strong correlations (correlation coefficient, R2 > 0.9) between 21 compounds and 153 transcripts. Furthermore, the comprehensive analysis and characterization of the genes involved in lignan pathways and the metabolite profiles of lignans are expected to provide better insight regarding the diversity of the chemical composition, synthetic characteristics, and regulatory mechanisms of this medical herb.

4.
Genes (Basel) ; 11(1)2019 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-31888085

RESUMO

BACKGROUND: Hosta plantaginea (Lam.) Aschers (HPA), a species in the family Liliaceae, is an important landscaping plant and herbaceous ornamental flower. However, because the flower has only two colors, white and purple, color matching applications are extremely limited. To date, the mechanism underlying flower color regulation remains unclear. METHODS: In this study, the transcriptomes of three cultivars-H. plantaginea (HP, white flower), H. Cathayana (HC, purple flower), and H. plantaginea 'Summer Fragrance' (HS, purple flower)-at three flowering stages (bud stage, initial stage, and late flowering stage) were sequenced with the Illumina HiSeq 2000 (San Diego, CA, USA). The RNA-Seq results were validated by qRT-PCR of eight differentially expressed genes (DEGs). Then, we further analyzed the relationship between anthocyanidin synthase (ANS), chalcone synthase (CHS), and P450 and the flower color regulation by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Eukaryotic Orthologous Groups (KOG) network and pathway enrichment analyses. The overexpression of CHS and ANS in transgenic tobacco petals was verified using qRT-PCR, and the petal colors associated with the overexpression lines were confirmed using absorbance values. RESULTS: Over 434,349 transcripts were isolated, and 302,832 unigenes were identified. Additionally, through transcriptome comparisons, 2098, 722, and 606 DEGs between the different stages were found for HP, HC, and HS, respectively. Furthermore, GO and KEGG pathway analyses showed that 84 color-related DEGs were enriched in 22 pathways. In particular, the flavonoid biosynthetic pathway, regulated by CHS, ANS, and the cytochrome P450-type monooxygenase gene, was upregulated in both purple flower varieties in the late flowering stage. In contrast, this gene was hardly expressed in the white flower variety, which was verified in the CHS and ANS overexpression transgenic tobacco petals. CONCLUSIONS: The results suggest that CHS, ANS, and the cytochrome P450s-regulated flavonoid biosynthetic pathway might play key roles in the regulation of flower color in HPA. These insights into the mechanism of flower color regulation could be used to guide artificial breeding of polychrome varieties of ornamental flowers.


Assuntos
Aciltransferases/genética , Perfilação da Expressão Gênica/métodos , Hosta/fisiologia , Oxigenases/genética , Tabaco/genética , Vias Biossintéticas , Cor , Flores/genética , Flores/fisiologia , Regulação da Expressão Gênica de Plantas , Sequenciamento de Nucleotídeos em Larga Escala , Hosta/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Locos de Características Quantitativas , Análise de Sequência de RNA , Tabaco/crescimento & desenvolvimento
5.
Chem Asian J ; 10(2): 461-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25403943

RESUMO

Three small organic molecules that contained a phenothiazine backbone and triphenylamine (TPA), carbazole (CZ), or anthracene (AN) as a terminal electron donor were synthesized and fabricated in ITO/organic film/Al sandwiched memory devices. The influence of the extent of conjugation in the three molecules on the performance of their corresponding devices was investigated and the results showed that all of the fabricated devices exhibited nonvolatile ternary WORM character, whilst the switch threshold voltages decreased on moving from TPA to CZ and AN, which is promising for low-power-consumption data storage. These results revealed that tailoring the extent of conjugation in the terminal electron donor in the D-A molecules could effectively optimize the device performance, in particular the switch-threshold voltage, which could be instructive for the design of low-energy-consumption memory materials.

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