DcWRKY75 promotes ethylene induced petal senescence in carnation ( Dianthus caryophyllus L.)

The senescence of carnation (Dianthus caryophyllus L.) flower petals is associated with increased synthesis of the phytohormone ethylene. This ethylene serves to initiate and regulate the processes of programmed cell death. We are using molecular approaches to study the regulation of ethylene biosynthesis in various floral organs during development and senescence of flowers. We have isolated and cloned mRNAs which encode the ethylene biosynthetic pathway enzymes s-adenosylmethionine (SAM) synthetase, 1-aminocyclopropane-1-carboxylate (ACC) synthase and the ethylene forming enzyme (EFE) from carnation flower petals. These cDNAs have been used as molecular probes to determine the steady-state mRNA levels of these transcripts in senescing flowers. The increase in ethylene associated with petal senescence is accompanied by a dramatic increase in the abundance of transcripts for both ACC synthase and EFE. In striking contrast, the level of SAM synthetase mRNA decreases significantly with the onset of petal senescence. Genomic DNA Southern blots reveal both ACC synthase and EFE are encoded by multigene families. We have recently isolated several genomic clones from carnation which represent different ACC synthase genes. The structure and organization of these gene will be presented.

Download Full-text

Physiological and Molecular Characterization of the Response to Ethylene during Senescence of Carnation Genotypic Variants

10.32747/1995.7613011.bard ◽

1995 ◽

Author(s):

William Woodson ◽

Shimon Mayak ◽

Haim Rabinowitch

Keyword(s):

Ethylene Production ◽

Dianthus Caryophyllus ◽

Acc Oxidase ◽

Acc Synthase ◽

Early Response ◽

Vase Life ◽

Petal Senescence ◽

Ethylene Treatment ◽

Novel Proteins ◽

Exogenous Ethylene

The senescence of carnation (Dianthus caryophyllus L.) flowers is associated with increased production of the phytohormone ethylene, which in turn serves to initiate and regulate the processes involved in programmed petal death. We investigated the regulation of ethylene production and petal senescence in carnation. Several carnation genotypes were identified that exhibited extended vase-life in comparison to flowers from typical commercial cultivars. The capacity of these genotypes to produce ethylene during postharvest vase-life and to respond to exogenous ethylene was investigated. Several genotypes, represented by 'Sandrosa' and 87-37G produced little ethylene durig their postharvest vase-life and as a result failed to exhibit the symptoms (in-rolling and wilting) typical of flowers producing elevated levels of ethylene. These genotypes were further separated by their capacity to respond to exogenous ethylene by both increased ethylene synthesis and premature petal senescence. In one case a genotype (799) was identified that was not capable of responding to exogenous ethylene by either increased ethylene production or premature petal senescence. The regulation of ethylene production during petal senescence was investigated both at the enzyme and gene levels. A full length cDNA was identified for the petal senescence-related ACC synthase gene. Utilizing this, and other ethylene biosynthetic pathway cDNA probes, an increase in both ACC synthase and ACC oxidase mRNAs were detected following ethylene treatment. An increase in ACC oxidase mRNA and enzyme activity was detected within 2-3 h following ethylene treatment, indicating the expression of this gene is an early response to ethylene. An investigation into the expression of novel proteins during petal senescence revealed a number of polypeptides increased in abundance and possibly play a role in the regulation or biochemical processes of senescence. One polypeptide of 70 kDa was identified as being encoded by the previously characterized gene SR12 and possibly represents a b-galactosidase involved in the remobilization of carbohydrates during senescence.

Download Full-text

Histone H3K4 methyltransferase DcATX1 promotes ethylene induced petal senescence in carnation

10.1101/2022.01.12.476045 ◽

2022 ◽

Author(s):

Shan Feng ◽

Ruiming Wang ◽

Hualiang Tan ◽

Linlin Zhong ◽

Yunjiang Cheng ◽

...

Keyword(s):

Epigenetic Regulation ◽

Dianthus Caryophyllus ◽

Petal Senescence ◽

Histone Lysine ◽

Histone Lysine Methyltransferase ◽

Lysine Methyltransferase ◽

Histone H3k4 ◽

Arabidopsis Homolog ◽

Complex Regulatory Network ◽

Senescence Associated Genes

Petal senescence is controlled by a complex regulatory network. Epigenetic regulation like histone modification influences chromatin state and gene expression. However, involvement of histone methylation in regulating petal senescence is still largely unknown. Here, we found that the trimethylation of histone H3 at Lysine 4 (H3K4me3) is increased during the ethylene induced petal senescence in carnation (Dianthus caryophyllus L.). The H3K4me3 levels are positively associated with the expression of transcription factor DcWRKY75, ethylene biosynthetic genes DcACS1 and DcACO1, and senescence associated genes (SAGs) DcSAG12 and DcSAG29. Further, we identified that carnation DcATX1 (ARABIDOPSIS HOMOLOG OF TRITHORAX1) encodes a histone lysine methyltransferase which can methylate H3K4. Knockdown of DcATX1 delays ethylene induced petal senescence in carnation, which is associated with the downregulated expression of DcWRKY75, DcACO1 and DcSAG12. While overexpression of DcATX1 exhibits the opposite effects. DcATX1 promotes the transcription of DcWRKY75, DcACO1 and DcSAG12 by targeting to their promoters to elevate the H3K4me3 levels. Overall, our results demonstrate that DcATX1 is a H3K4 methyltransferase that promotes the expression of DcWRKY75, DcACO1 and DcSAG12 by regulating H3K4me3 levels, thereby accelerating ethylene induced petal senescence in carnation. This study further indicates that epigenetic regulation is important for plant senescence process.

Download Full-text

Role of the Gynoecium in Cytokinin-induced Carnation Petal Senescence

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.116.4.676 ◽

1991 ◽

Vol 116 (4) ◽

pp. 676-679 ◽

Cited By ~ 9

Author(s):

William R. Woodson ◽

Amanda S. Brandt

Keyword(s):

Ethylene Production ◽

Dianthus Caryophyllus ◽

Petal Senescence

Treatment of cut carnation (Dianthus caryophyllus L. `White Sim') flowers with the synthetic cytokinin benzyladenine (BA) at concentrations >1.0 μm induced premature petal senescence. Flowers treated with 100 μm BA exhibited elevated ethylene production in styles and petals before untreated flowers. The gynoecia of BA-treated flowers accumulated 1-aminocyclopropane-l-carboxyllc acid (ACC) and enlarged before untreated flowers. Removal of the gynoecium (ovary and styles) or styles prevented BA-induced petal senescence and resulted in a substantial delay in petal senescence. In contrast, removal of the gynoecium had no effect on timing of petal senescence in flowers held in water. These results indicate BA stimulates petal senescence by inducing premature ACC accumulation and ethylene production in the gynoecium.

Download Full-text

Hydrogen Nanobubble Water Delays Petal Senescence and Prolongs the Vase Life of Cut Carnation (Dianthus caryophyllus L.) Flowers

Plants ◽

10.3390/plants10081662 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1662

Author(s):

Longna Li ◽

Qianlan Yin ◽

Tong Zhang ◽

Pengfei Cheng ◽

Sheng Xu ◽

...

Keyword(s):

Dianthus Caryophyllus ◽

Hydrogen Gas ◽

Agricultural Products ◽

Vase Life ◽

Oxygen Species ◽

Cut Flowers ◽

Fresh Weight ◽

Petal Senescence ◽

Increasing Trend ◽

Dissolved Hydrogen

The short vase life of cut flowers limits their commercial value. To ameliorate this practical problem, this study investigated the effect of hydrogen nanobubble water (HNW) on delaying senescence of cut carnation flowers (Dianthus caryophyllus L.). It was observed that HNW had properties of higher concentration and residence time for the dissolved hydrogen gas in comparison with conventional hydrogen-rich water (HRW). Meanwhile, application of 5% HNW significantly prolonged the vase life of cut carnation flowers compared with distilled water, other doses of HNW (including 1%, 10%, and 50%), and 10% HRW, which corresponded with the alleviation of fresh weight and water content loss, increased electrolyte leakage, oxidative damage, and cell death in petals. Further study showed that the increasing trend with respect to the activities of nucleases (including DNase and RNase) and protease during vase life period was inhibited by 5% HNW. The results indicated that HNW delayed petal senescence of cut carnation flowers through reducing reactive oxygen species accumulation and initial activities of senescence-associated enzymes. These findings may provide a basic framework for the application of HNW for postharvest preservation of agricultural products.

Download Full-text

Cloning and Characterization of a cDNA Encoding a Putative Nuclease Related to Petal Senescence in Carnation (Dianthus caryophyllus L.) Flowers

Engei Gakkai zasshi ◽

10.2503/jjshs.75.323 ◽

2006 ◽

Vol 75 (4) ◽

pp. 323-327 ◽

Cited By ~ 4

Author(s):

Takako Narumi ◽

Rie Sudo ◽

Shigeru Satoh

Keyword(s):

Dianthus Caryophyllus ◽

Petal Senescence

Download Full-text

Variation in Flower Senescence and Ethylene Biosynthesis among Carnations

HortScience ◽

10.21273/hortsci.27.10.1100 ◽

1992 ◽

Vol 27 (10) ◽

pp. 1100-1102 ◽

Cited By ~ 17

Author(s):

Amanda S. Brandt ◽

William R. Woodson

Keyword(s):

Dianthus Caryophyllus ◽

Acc Synthase ◽

Ethylene Biosynthesis ◽

Enzyme Treatment ◽

Flower Senescence ◽

Vase Life ◽

Petal Senescence ◽

Ethylene Treatment ◽

Initial Symptoms ◽

Visible Symptom

We have investigated the patterns of ethylene biosynthesis in carnation (Dianthus caryophyllus L.) genotypes that exhibit extended vase life in comparison to flowers of White Sim'. `White Sim' flowers exhibited typical symptoms of senescence, including petal in-rolling and rapid wilting, beginning 5 days after harvest. In contrast, the other genotypes studied did not show petal in-rolling or rapid wilting associated with petal senescence. The first visible symptom of senescence in these flowers was necrosis of the petal tips, and it occurred from 3 to 7 days after the initial symptoms of senescence were seen in `White Sim' flowers. In all cases, the extended-vase-life genotypes did not exhibit the dramatic increase in ethylene production that typically accompanies petal senescence in carnation. This appeared to be the result of limited accumulation of ACC. In addition, flowers of these genotypes had limited capacity to convert ACC to ethylene. Therefore, we conclude that the low level of ethylene produced by these flowers during postharvest aging is the result of low activities of both ACC synthase and the ethylene-forming enzyme. Treatment of `White Sim' flowers at anthesis with 1.0 μl ethylene/liter resulted in the induction of increased ethylene biosynthesis and premature petal senescence. The extended-vase-life genotypes exhibited varying responses to ethylene treatment. One genotype (87-37G-2) produced elevated ethylene and senesced prematurely, as did flowers of `White Sim'. A second genotype (82-1) was induced to senesce by ethylene treatment but did not produce increased ethylene. A third genotype (799) was unaffected by ethylene treatment. The results of this study suggest these extended-vase-life genotypes are representative of genetic differences in the capacity to synthesize and respond to ethylene. Chemical name used: 1-aminocyclopropane-1-carboxylic acid (ACC).

Download Full-text

Influence of growth regulators and explants on shoot regeneration in carnation

Horticultural Science ◽

10.17221/1/2009-hortsci ◽

2009 ◽

Vol 36 (No. 4) ◽

pp. 140-146 ◽

Cited By ~ 4

Author(s):

J.K. Kanwar ◽

S. Kumar

Keyword(s):

Acetic Acid ◽

Shoot Regeneration ◽

Growth Regulators ◽

Dianthus Caryophyllus ◽

Naphthalene Acetic Acid ◽

Ms Medium ◽

Shoot Bud ◽

Dichlorophenoxy Acetic Acid ◽

Number Of Shoots

The influence of growth regulators, explants and their interactions on in vitro shoot bud formation from callus was studied in <I>Dianthus caryophyllus</I> L. The leaf and internode explants were cultured on Murashige and Skoog (MS) medium containing different concentrations of growth regulators. The highest callus induction was observed with 2 mg/l 2,4-dichlorophenoxy acetic acid (2,4-D) and 1 mg/l benzyl adenine (BA). Out of twenty seven shoot regeneration media tested, only 2 mg/l thidiazuron (TDZ) and zeatin alone or in combination with naphthalene acetic acid (NAA) and/or indole acetic acid (IAA) could differentiate calli. The highest average number of shoots was observed with 2 mg/l TDZ and 1 mg/l IAA. Significant differences were observed in calli producing shoots and number of shoots per callus in the explants of leaf and internode. The shoots were elongated and multiplied on MS medium supplemented with 1 mg/l BA and solidified with 1% agar. The shoots were rooted and hardened with 76% survival success in pots after six weeks of transfer to the pots.

Download Full-text