Mechanism Underlying the Shading-Induced Chlorophyll Accumulation in Tea Leaves

Besides aroma and taste, the color of dry tea leaves, tea infusion, and infused tea leaves is also an important index for tea quality. Shading can significantly increase the chlorophyll content of tea leaves, leading to enhanced tea leaf coloration. However, the underlying regulatory mechanism remains unclear. In this study, we revealed that the expressions of chlorophyll synthesis genes were significantly induced by shading, specially, the gene encoding protochlorophyllide oxidoreductase (CsPOR). Indoor control experiment showed that decreased light intensity could significantly induce the expression of CsPOR, and thus cause the increase of chlorophyll content. Subsequently, we explored the light signaling pathway transcription factors regulating chlorophyll synthesis, including CsPIFs and CsHY5. Through expression level and subcellular localization analysis, we found that CsPIF3-2, CsPIF7-1, and CsHY5 may be candidate transcriptional regulators. Transcriptional activation experiments proved that CsHY5 inhibits CsPORL-2 transcription. In summary, we concluded that shading might promote the expression of CsPORL-2 by inhibiting the expression of CsHY5, leading to high accumulation of chlorophyll in tea leaves. The results of this study provide insights into the mechanism regulating the improvements to tea plant quality caused by shading.

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Effects of Simulated Acid Rain and Aluminum Enrichment on Growth and Photosynthesis of Tea Seedlings

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.610-613.181 ◽

2012 ◽

Vol 610-613 ◽

pp. 181-185 ◽

Cited By ~ 1

Author(s):

Xiao Hua Duan ◽

Xiao Fei Hu ◽

Fu Sheng Chen ◽

Ze Yuan Deng

Keyword(s):

Acid Rain ◽

Chlorophyll Content ◽

Combined Treatment ◽

Tea Plant ◽

Simulated Acid Rain ◽

Tea Leaves ◽

Tea Production ◽

Al Addition ◽

Tea Plants ◽

Photosynthesis Capacity

The effects of simulated acid rain and aluminum (Al) addition on growth and photosynthesis physiology of tea plants (Camellia sinensis L.) were studied with tea seedlings in a hydroculture experiment. Results showed that the growth of tea plant, chlorophyll content, and photosynthesis (Pn) of tea leaves were better in the treatments of suitable Al addition (10 mg/L and/or 20 mg/L) than the treatments without Al addition and higher Al addition (30 mg/L). The growth of tea plant increased with increasing acidity of acid rain, while the leaves of tea plant showed more chlorophyll content and higher Pn at the treatment of pH 4.0 than pH 5.0 and pH 3.0 acid solutions. The growth of tea plant, chlorophyll content and Pn were the best at the combined treatment of suitable Al addition (10~20 mg/L) and moderate acidity of acid rain (pH 4.0), while the slowest at the combined treatment of 30 mg/L Al and pH 3.0 acid rain. These results suggested that suitable Al and moderate acidity of acid rain are helpful to increase tea production by increasing photosynthesis capacity.

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Exogenous abscisic acid induces on lipid and flavonoid metabolism of tea plant under drought stress

10.21203/rs.2.14448/v1 ◽

2019 ◽

Author(s):

Zhongshuai Gai ◽

Yu Wang ◽

Yiqian Ding ◽

Wenjun Qian ◽

Hui Xie ◽

...

Keyword(s):

Abscisic Acid ◽

Lipid Metabolism ◽

Drought Stress ◽

Tca Cycle ◽

Chlorophyll Synthesis ◽

Tea Plant ◽

Flavonoid Biosynthesis ◽

Regulation Mechanism ◽

Tea Leaves ◽

Exogenous Aba

Abstract Background: Abscisic acid (ABA) is an important phytohormone responsible for activating drought resistance, but the regulation mechanism of exogenous ABA on tea plants under drought stress was rarely reported. Results: The results showed that the exogenous ABA significantly induced the metabolic pathways of tea leaves under drought stress, including the chlorophyll synthesis, photosynthesis, sucrose and starch metabolism, TCA cycle, glycolysis, lipid metabolism and flavonoids biosynthesis. In which, the exogenous ABA could up-regulated the genes related to lipid metabolism and flavonoid biosynthesis, including LPCAT , ALDH, FLS, CHI, DFR, and down-regulated the genes related to lipid metabolism and flavonoid biosynthesis, including FATB, EKI, DGK , PAL, 4CL . The exogenous ABA could also increase the contents of flavone, anthocyanins, flavonol, isoflavone of tea leaves under drought stress, including delphinidin 3-O-glucosidewere, cyanidin 3-O-rutinoside, kaempferitrin, sakuranetin, prunetin, kaempferol, and decrease the contents of glycerophospholipids, glycerolipids and fatty acids of tea leaves under drought stress, including LysoPE 14:0, LysoPE 16:0, LysoPE 18:0, LysoPE 18:1, LysoPC 15:1 and LysoPC 16:0. And there were strong correlations between the genes and metabolites. Conclusions: The results suggested that the exogenous ABA could alleviate the damages of tea leaves under drought stress through inducing the expressions of the genes and altering the contents of metabolites in response to drought stress. The data also provide a good foundation for further research on the roles of the genes and metabolites in response to ABA.

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CmNAC73 Mediates the Formation of Green Color in Chrysanthemum Flowers by Directly Activating the Expression of Chlorophyll Biosynthesis Genes HEMA1 and CRD1

Genes ◽

10.3390/genes12050704 ◽

2021 ◽

Vol 12 (5) ◽

pp. 704

Author(s):

Jing Luo ◽

Huan Wang ◽

Sijia Chen ◽

Shengjing Ren ◽

Hansen Fu ◽

...

Keyword(s):

Chlorophyll Biosynthesis ◽

Flower Color ◽

Chlorophyll Synthesis ◽

Chrysanthemum Morifolium ◽

Gene Encoding ◽

Chlorophyll Metabolism ◽

Chlorophyll Accumulation ◽

Transient Overexpression ◽

Highly Correlated ◽

Dark Green

Chrysanthemum is one of the most beautiful and popular flowers in the world, and the flower color is an important ornamental trait of chrysanthemum. Compared with other flower colors, green flowers are relatively rare. The formation of green flower color is attributed to the accumulation of chlorophyll; however, the regulatory mechanism of chlorophyll metabolism in chrysanthemum with green flowers remains largely unknown. In this study, we performed Illumina RNA sequencing on three chrysanthemum materials, Chrysanthemum vestitum and Chrysanthemum morifolium cultivars ‘Chunxiao’ and ‘Green anna,’ which produce white, light green and dark green flowers, respectively. Based on the results of comparative transcriptome analysis, a gene encoding a novel NAC family transcription factor, CmNAC73, was found to be highly correlated to chlorophyll accumulation in the outer whorl of ray florets in chrysanthemum. The results of transient overexpression in chrysanthemum leaves showed that CmNAC73 acts as a positive regulator of chlorophyll biosynthesis. Furthermore, transactivation and yeast one-hybrid assays indicated that CmNAC73 directly binds to the promoters of chlorophyll synthesis-related genes HEMA1 and CRD1. Thus, this study uncovers the transcriptional regulation of chlorophyll synthesis-related genes HEMA1 and CRD1 by CmNAC73 and provides new insights into the development of green flower color in chrysanthemum and chlorophyll metabolism in plants.

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Abiotic-stress induces demethylation and transcriptional activation of a gene encoding a glycerophosphodiesterase-like protein in tobacco plants

Molecular Genetics and Genomics ◽

10.1007/s00438-007-0209-1 ◽

2007 ◽

Vol 277 (5) ◽

pp. 589-600 ◽

Cited By ~ 200

Author(s):

Chang-Sun Choi ◽

Hiroshi Sano

Keyword(s):

Abiotic Stress ◽

Transcriptional Activation ◽

Gene Encoding ◽

Tobacco Plants

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The orphan nuclear receptor NGFI-B regulates expression of the gene encoding steroid 21-hydroxylase

Molecular and Cellular Biology ◽

10.1128/mcb.13.2.861-868.1993 ◽

1993 ◽

Vol 13 (2) ◽

pp. 861-868

Author(s):

T E Wilson ◽

A R Mouw ◽

C A Weaver ◽

J Milbrandt ◽

K L Parker

Keyword(s):

Nuclear Receptor ◽

Transcriptional Activation ◽

Core Promoter ◽

Orphan Nuclear Receptor ◽

Recognition Sequence ◽

Mobility Shift ◽

Adrenocortical Cells ◽

Gene Encoding ◽

Adult Rat ◽

Gel Mobility Shift

As part of its trophic action to maintain the steroidogenic capacity of adrenocortical cells, corticotropin (ACTH) increases the transcription of the cytochrome P-450 steroid hydroxylase genes, including the gene encoding steroid 21-hydroxylase (21-OHase). We previously identified several promoter elements that regulate 21-OHase gene expression in mouse Y1 adrenocortical tumor cells. One of these elements, located at nucleotide -65, closely resembles the recognition sequence of the orphan nuclear receptor NGFI-B, suggesting that NGFI-B regulates this essential steroidogenic enzyme. To explore this possibility, we first used in situ hybridization to demonstrate high levels of NGFI-B transcripts in the adrenal cortex of the adult rat. In cultured mouse Y1 adrenocortical cells, treatment with ACTH, the major regulator of 21-OHase transcription, rapidly increased NGFI-B expression. Gel mobility shift and DNase I footprinting experiments showed that recombinantly expressed NGFI-B interacts specifically with the 21-OHase -65 element and identified one complex formed by Y1 extracts and the 21-OHase -65 element that contains NGFI-B. Expression of NGFI-B significantly augmented the activity of the intact 21-OHase promoter, while mutations of the -65 element that abolish NGFI-B binding markedly diminished NGFI-B-mediated transcriptional activation. Specific mutations of NGFI-B shown previously to impair either DNA binding or transcriptional activation diminished the effect of NGFI-B coexpression on 21-OHase expression. Finally, an oligonucleotide containing the NGFI-B response element conferred ACTH response to a core promoter from the prolactin gene, showing that this element is sufficient for ACTH induction. Collectively, these results identify a cellular promoter element that is regulated by NGFI-B and implicate NGFI-B in the transcriptional induction of 21-OHase by ACTH.

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Activation of the Akt1-CREB pathway promotes RNF146 expression to inhibit PARP1-mediated neuronal death

Science Signaling ◽

10.1126/scisignal.aax7119 ◽

2020 ◽

Vol 13 (663) ◽

pp. eaax7119

Author(s):

Hyojung Kim ◽

Jisoo Park ◽

Hojin Kang ◽

Seung Pil Yun ◽

Yun-Song Lee ◽

...

Keyword(s):

Chlorogenic Acid ◽

Transcriptional Activation ◽

Dopaminergic Neurons ◽

Cultured Cells ◽

Intraperitoneal Administration ◽

Neuronal Loss ◽

Postmortem Brain ◽

Dependent Manner ◽

Gene Encoding ◽

Creb Pathway

Progressive degeneration of dopaminergic neurons characterizes Parkinson’s disease (PD). This neuronal loss occurs through diverse mechanisms, including a form of programmed cell death dependent on poly(ADP-ribose) polymerase-1 (PARP1) called parthanatos. Deficient activity of the kinase Akt1 and aggregation of the protein α-synuclein are also implicated in disease pathogenesis. Here, we found that Akt1 suppressed parthanatos in dopaminergic neurons through a transcriptional mechanism. Overexpressing constitutively active Akt1 in SH-SY5Y cells or culturing cells with chlorogenic acid (a polyphenol found in coffee that activates Akt1) stimulated the CREB-dependent transcriptional activation of the gene encoding the E3 ubiquitin ligase RNF146. RNF146 inhibited PARP1 not through its E3 ligase function but rather by binding to and sequestering PAR, which enhanced the survival of cultured cells exposed to the dopaminergic neuronal toxin 6-OHDA or α-synuclein aggregation. In mice, intraperitoneal administration of chlorogenic acid activated the Akt1-CREB-RNF146 pathway in the brain and provided neuroprotection against both 6-OHDA and combinatorial α-synucleinopathy in an RNF146-dependent manner. Furthermore, dysregulation of the Akt1-CREB pathway was observed in postmortem brain samples from patients with PD. The findings suggest that therapeutic restoration of RNF146 expression, such as by activating the Akt1-CREB pathway, might halt neurodegeneration in PD.

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Chilling-induced chlorosis in maize (Zea mays)

Canadian Journal of Botany ◽

10.1139/b85-089 ◽

1985 ◽

Vol 63 (4) ◽

pp. 711-715 ◽

Cited By ~ 4

Author(s):

R. Hodgins ◽

R. B. van Huystee

Keyword(s):

Zea Mays ◽

Chlorophyll Content ◽

Sweet Corn ◽

Aminolevulinic Acid ◽

Chlorophyll Synthesis ◽

Carotenoid Content ◽

Control Tissue ◽

Etiolated Seedlings ◽

Chilling Temperatures ◽

And Control

The effect of chilling temperatures on the porphyrin pathway leading to chlorophyll was studied in Seneca Chief hybrid sweet corn. One-week-old seedlings grown at 28 °C in a 14 h light: 10 h dark photoperiod synthesize negligible amounts of chlorophyll when exposed to 12 °C for a subsequent 6 d. When the chilled plant is then brought back to 28 °C, chlorophyll synthesis is restored to control levels. Little difference in carotenoid content was detected between chill-stressed and control tissue even after 4 d of stress. Small differences in the chlorophyll content per 106 chloroplasts could be detected between stressed and control seedlings. Etiolated seedlings synthesize negligible amounts of chlorophyll or its precursors when illuminated at 12 °C. Incubation of tissue with aminolevulinic acid at various temperatures from 12 to 22 °C resulted in an accumulation of precursors comparable to 28 °C control tissue. The ability of etiolated tissue to accumulate aminolevulinic acid was negligible when illuminated at 12 °C as compared with that in tissue illuminated at 28 °C.

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Low Caffeine Content in Novel Grafted Tea with Camellia sinensis as Scions and Camellia oleifera as Stocks

Natural Product Communications ◽

10.1177/1934578x1501000522 ◽

2015 ◽

Vol 10 (5) ◽

pp. 1934578X1501000 ◽

Cited By ~ 2

Author(s):

Wei-Wei Deng ◽

Min Li ◽

Chen-Chen Gu ◽

Da-Xiang Li ◽

Lin-Long Ma ◽

...

Keyword(s):

Camellia Sinensis ◽

Expression Patterns ◽

Tea Plant ◽

Protein Accumulation ◽

Tea Leaves ◽

Qrt Pcr ◽

Caffeine Content ◽

Caffeine Synthase ◽

Specificity And Sensitivity ◽

Tea Plants

Caffeine, a purine alkaloid, is a major secondary metabolite in tea leaves. The demand for low caffeine tea is increasing in recent years, especially for health reasons. We report a novel grafted tea material with low caffeine content. The grafted tea plant had Camellia sinensis as scions and C. oleifera as stocks. The content of purine alkaloids was determined in the leaves of one-year-old grafted tea plants by HPLC. We also characterized caffeine synthase (CS), a key enzyme involved in caffeine biosynthesis in tea plants, at the expression level. The expression patterns of CS were examined in grafted and control leaves by Western blot, using a self-prepared polyclonal antibody with high specificity and sensitivity. The expression of related genes ( TCS1, tea caffeine synthase gene, GenBank accession No. AB031280; sAMS, SAM synthetase gene, AJ277206; TIDH, IMP dehydrogenase gene, EU106658) in the caffeine biosynthetic pathway was investigated by qRT-PCR. HPLC showed that the caffeine content was only 38% as compared with the non-grafted tea leaves. Immunoblotting analysis showed that CS protein decreased by half in the leaves of grafted tea plants. qRT-PCR revealed no significant changes in the expression of two genes in the upstream pathway ( sAMS and TIDH), while the expression of TCS1 was greatly decreased (50%). Taken together, these data revealed that the low caffeine content in the grafted tea leaves is due to low TCS1 expression and CS protein accumulation.

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Adenovirus E1A specifically blocks SWI/SNF-dependent transcriptional activation.

Molecular and Cellular Biology ◽

10.1128/mcb.16.10.5737 ◽

1996 ◽

Vol 16 (10) ◽

pp. 5737-5743 ◽

Cited By ~ 18

Author(s):

M E Miller ◽

B R Cairns ◽

R S Levinson ◽

K R Yamamoto ◽

D A Engel ◽

...

Keyword(s):

Transcriptional Activation ◽

Cellular Transformation ◽

Transcriptional Coactivator ◽

Gene Encoding ◽

Adenovirus E1a ◽

Transcriptional Regulatory ◽

Genes Encoding ◽

Regulatory Complex ◽

Activation Pathways ◽

Coactivator P300

Expression of the adenovirus E1A243 oncoprotein in Saccharomyces cerevisiae produces a slow-growth phenotype with accumulation of cells in the G1 phase of the cell cycle. This effect is due to the N-terminal and CR1 domains of E1A243, which in rodent cells are involved in triggering cellular transformation and also in binding to the cellular transcriptional coactivator p300. A genetic screen was undertaken to identify genes required for the function of E1A243 in S. cerevisiae. This screen identified SNF12, a gene encoding the 73-kDa subunit of the SWI/SNF transcriptional regulatory complex. Mutation of genes encoding known members of the SWI/SNF complex also led to loss of E1A function, suggesting that the SWI/SNF complex is a target of E1A243. Moreover, expression of E1A in wild-type cells specifically blocked transcriptional activation of the INO1 and SUC2 genes, whose activation pathways are distinct but have a common requirement for the SWI/SNF complex. These data demonstrate a specific functional interaction between E1A and the SWI/SNF complex and suggest that a similar interaction takes place in rodent and human cells.

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