scholarly journals Transcriptome Reveals Roles of Lignin-Modifying Enzymes and Abscisic Acid in the Symbiosis of Mycena and Gastrodia elata

2021 ◽  
Vol 22 (12) ◽  
pp. 6557
Author(s):  
Li-Ying Ren ◽  
Heng Zhao ◽  
Xiao-Ling Liu ◽  
Tong-Kai Zong ◽  
Min Qiao ◽  
...  
Keyword(s):  
Biological Activity ◽  
Abscisic Acid ◽  
Lignin Degradation ◽  
Molecular Mechanisms ◽  
Receptor Protein ◽  
Gastrodia Elata ◽  
Upregulated Genes ◽  
Aba Biosynthesis ◽  
Seed Coats

Gastrodia elata is a well-known medicinal and heterotrophic orchid. Its germination, limited by the impermeability of seed coat lignin and inhibition by abscisic acid (ABA), is triggered by symbiosis with fungi such as Mycena spp. However, the molecular mechanisms of lignin degradation by Mycena and ABA biosynthesis and signaling in G. elata remain unclear. In order to gain insights into these two processes, this study analyzed the transcriptomes of these organisms during their dynamic symbiosis. Among the 25 lignin-modifying enzyme genes in Mycena, two ligninolytic class II peroxidases and two laccases were significantly upregulated, most likely enabling Mycena hyphae to break through the lignin seed coats of G. elata. Genes related to reduced virulence and loss of pathogenicity in Mycena accounted for more than half of annotated genes, presumably contributing to symbiosis. After coculture, upregulated genes outnumbered downregulated genes in G. elata seeds, suggesting slightly increased biological activity, while Mycena hyphae had fewer upregulated than downregulated genes, indicating decreased biological activity. ABA biosynthesis in G. elata was reduced by the downregulated expression of 9-cis-epoxycarotenoid dioxygenase (NCED-2), and ABA signaling was blocked by the downregulated expression of a receptor protein (PYL12-like). This is the first report to describe the role of NCED-2 and PYL12-like in breaking G. elata seed dormancy by reducing the synthesis and blocking the signaling of the germination inhibitor ABA. This study provides a theoretical basis for screening germination fungi to identify effective symbionts and for reducing ABA inhibition of G. elata seed germination.

The Effects of Abscisic Acid on Photosynthesis in Tomato Under Sub-High Temperature and High Light Stress

2016 ◽  
Vol 13 (10) ◽  
pp. 7189-7198
Author(s):  
Shuang Gang ◽  
Yufeng Liu ◽  
Tao Lu ◽  
Mingfang Qi ◽  
Xiaoxi Guan ◽  
...  
Keyword(s):  
Abscisic Acid ◽  
High Temperature ◽  
Light Stress ◽  
High Light ◽  
Exogenous Aba ◽  
Photosystems I And Ii ◽  
Genes Expression ◽  
Irreversible Reduction ◽  
Aba Biosynthesis

The present study investigated the role of abscisic acid (ABA) application in photosynthesis, photosystems I and II (PSI and PSII), antioxidant system and ABA-related genes expression under sub-high temperature and high light (STHL) stress. STHL treatment led to an irreversible reduction in the photosynthetic rate (Pn), damaged PSII firstly at three hours, and then inhibited RuBPCase activity at seven hours, at last injured PSI after eleven hours. During 11 hours STHL stress, exogenous ABA can alleviate the degree of Pn decreasing, improve the activity of RuBPCase, protect PSII to photoinhibition, and promote the ability of reactive oxygen removal. When severe stress occured, exogenous ABA has certain effect, but can not ease photoinhibition and photodamage. In addition, exogenous ABA effected significantly on genes of upstream regulatory ABA biosynthesis key enzymes and downstream response MYB transcription factors.

scholarly journals The Role of Abscisic Acid in Heat Stress-induced Secondary Dormancy in Apple Seeds

HortScience ◽  
1991 ◽  
Vol 26 (2) ◽  
pp. 175-177 ◽  
Author(s):  
Jocelyn A. Ozga ◽  
F.G. Dennis
Keyword(s):  
Abscisic Acid ◽  
Heat Stress ◽  
Germination Capacity ◽  
Embryonic Axes ◽  
Secondary Dormancy ◽  
Golden Delicious ◽  
Aba Content ◽  
Seed Coats ◽  
Apple Seeds

Exposure of stratified apple (Malus domestics Borkh. cv. Golden Delicious) seeds to 30C induces secondary dormancy. To determine if an increase in abscisic acid (ABA) content was associated with the loss in germination capacity, stratified seeds (3,- 6, or 9 weeks at 5C) were held at 30C for 0, 3, or 6 days. Stratification at 5C either had no effect or increased ABA content in embryonic axes, cotyledons, and seed coats. Exposure to 30C after stratification either did not affect or decreased ABA content of embryonic axes and seed coats; in contrast, cotyledonary ABA was increased. Seed coats, cotyledons, and embryonic axes stratified for 3, 6, or 9 weeks at 20C contained the same or higher levels of ABA in comparison with nonstratified seeds or seeds stratified at SC. Changes in ABA levels were not consistently correlated with changes in germination capacity during stratification or after exposure to 30C. These data suggest that changes in ABA are not related to changes in dormancy. Chemical names used: abscisic acid (ABA); butylated hydroxy-toluene (BHT); n-(trichloromethyl) thio-4-cyclohexene-1,2-dicarboximide(Captan).

Integrative hormone and transcriptome analysis underline the role of abscisic acid in seed shattering of weedy rice

2021 ◽  
Author(s):  
Hong Lang ◽  
Yuting He ◽  
Fengcheng Li ◽  
Dianrong Ma ◽  
Jian Sun
Keyword(s):  
Abscisic Acid ◽  
Critical Role ◽  
Weedy Rice ◽  
Seed Shattering ◽  
High Degree ◽  
Aba Content ◽  
Potential Signal ◽  
Aba Biosynthesis ◽  
Indole 3 Acetic Acid

AbstractWeedy rice is one of the most severe weeds in paddy fields, characterized by its high degree of seed shattering. Abscisic acid (ABA) serves as an abscission-accelerating signal and plays a critical role during abscission. However, mechanisms that link ABA and seed shattering remain elusive. In this study, WR04-6 (shattering) and SN9816 (non-shattering) were used to investigate the expression levels of genes involved in ABA biosynthesis and to determine the levels of ABA in tissues collected from the abscission zone (AZ) and the spikelet. ABA content in WR04-6, particularly in AZ, was significantly higher than in SN9816, significantly increasing prior to abscission. RNA-Sequencing and further expression analyses showed that the expression of OsNCED, the key gene involved in ABA biosynthesis, coincided with the increase of ABA content in the AZ and significantly increased during the seed shattering process. Additionally, the expression analysis of genes related to biosynthesis and metabolism of indole-3-acetic acid, gibberellin acid, and ethylene showed the greatest fold-change. Phytohormone levels associated with ABA co-expression-prediction revealed a potential signal transduction network among plant hormones involved in the regulation of seed abscission. Taken together, data presented in this study suggest that ABA contributes to seed shattering and transiently cooperates with other hormones, triggering a hormone imbalance that leads to the downstream activation of the AZ.

scholarly journals Possible role of transforming growth factor β as a marker cytokine of type 3 T-helpers in atopic dermatitis pathogenesis

2004 ◽  
Vol 3 (3) ◽  
pp. 27-31
Author(s):  
N. A. Pronina ◽  
V. S. Sviridova ◽  
A. A. Denisov ◽  
V. V. Klimov ◽  
Ye. N. Kologrivova
Keyword(s):  
Atopic Dermatitis ◽  
Biological Activity ◽  
Growth Factor ◽  
Molecular Mechanisms ◽  
Transforming Growth Factor ◽  
Allergic Inflammation ◽  
Transforming Growth Factor Β ◽  
Cell Populations ◽  
Type 3

The role of transforming growth factor β (TGF-β) in atopic dermatitis pathogenesis is discussed basing on the analysis of existing data of cellular and molecular mechanisms of allergic inflammation. Up-to date data of the main T-helper (T-h) lymphocyte subpopulations including Tx1, Tx2, Tx3 has been presented. Functions of regulatory T-cell populations and produced cytokines have been described. The main attention has been accented on the TGF-β structure and biological activity as a main Tx3 cytokine. The current information of TGF-β influence on different cell populations and its biological activity realization mechanism is thoroughly discussed. Information relating to the mechanism of cytokine regulation during atopic dermatitis has been summarized. A deep analysis of possible participation of TGF-β in disbalance formation on Tx1 and Tx2 levels, in disturbances of histological derma structure and allergic inflammation timing has been made.

The role of abscisic acid in germination of light-sensitive and light-insensitive lettuce seeds

1999 ◽  
Vol 9 (2) ◽  
pp. 129-134 ◽  
Author(s):  
Nurit Roth-Bejerano ◽  
Norbert J.A. Sedee ◽  
Rene M. van der Meulen ◽  
Mei Wang
Keyword(s):  
Abscisic Acid ◽  
Seed Germination ◽  
Inhibitory Processes ◽  
Exogenous Aba ◽  
Lettuce Seeds ◽  
Endogenous Level ◽  
Aba Content ◽  
Aba Biosynthesis ◽  
Light Break

AbstractThe role of abscisic acid (ABA) in seed germination of two cultivars of lettuce (Lactuca sativa L.; light-sensitive Ritsa and light-insensitive Strada) was investigated. The inhibition of Ritsa seed germination by exogenous ABA was higher than that of Strada seeds, the extent of inhibition of both cultivars being reduced by a short light break. At 25°C the sensitivity of both cultivars to exogenous ABA was higher than at 15°C. The endogenous level of ABA was similar in dry seeds of both cultivars, increasing temporarily in Ritsa seeds during the first 4 h of imbibition in darkness but not in Strada seeds, nor in Ritsa seeds exposed to a short light break. The transitory increase of ABA content in Ritsa seeds imbibed in darkness was accompanied by increased expression of the gene responsive to ABA (Rab) under these conditions. Zorial (Norflurazone), an ABA-biosynthesis inhibitor, decreased ABA content and allowed dark germination of the light-requiring Ritsa seeds. A short light break induced germination of Ritsa seeds when applied at 24 and 48 h after imbibition onset, i.e. after the transitory increase of ABA. GA3, on the other hand was effective when applied at the beginning of imbibition. It seems that light induces germination of the photoblastic Ritsa seeds by both inhibiting ABA synthesis and decreasing seed sensitivity to ABA and inhibitory processes induced by it.

Exploring the Benefits of Cellular Models to Uncover Bioactive Polyphenols for Neurodegeneration

2018 ◽  
Vol 24 (19) ◽  
pp. 2076-2106
Author(s):  
Rita Rosado-Ramos ◽  
Joana Godinho-Pereira ◽  
Ines Figueira ◽  
Carolina Jardim ◽  
Goncalo Garcia ◽  
...  
Keyword(s):  
Biological Activity ◽  
Neurodegenerative Diseases ◽  
Molecular Mechanisms ◽  
Protective Role ◽  
Bioactive Molecules ◽  
Cellular Models ◽  
In Vitro Systems

Our society is currently experiencing increased lifespan; one of the top causes for the high incidence of neurodegenerative disorders. The lack of effective treatments delaying or blocking disease progression has encouraged the active search for novel therapies. Many evidences support the protective role of phytochemicals in the prevention of neurodegenerative diseases, particularly (poly)phenols. In this review, we described the use of cellular-based models of neurodegenerative diseases and the benefits of their use as potent tools in the search for bioactive molecules, particularly (poly)phenols. Studies to assess the biological activity of (poly)phenols involve experimentation with in vitro and in vivo systems. In vitro systems are a useful tool as a first approach to test the underlined molecular mechanisms of candidate molecules. They can provide valuable information about biological activity, which can be then used to design animal and human intervention studies.

scholarly journals Integrative hormone and transcriptome analyses underline the role of abscisic acid in seed shattering of weedy rice

2020 ◽  
Author(s):  
Hong Lang ◽  
Yuting He ◽  
Jian Sun ◽  
Fengcheng Li ◽  
Dianrong Ma
Keyword(s):  
Abscisic Acid ◽  
Rice Variety ◽  
Critical Role ◽  
Weedy Rice ◽  
Seed Shattering ◽  
Expression Of Genes ◽  
Aba Content ◽  
Potential Signal ◽  
Aba Biosynthesis

Abstract Abstract Backgrounds: Weedy rice is one of the most severe weeds in paddy fields, strongly characterized by its high seed shattering level. Abscisic acid (ABA) serves as an abscission-accelerating signal and plays a critical role during abscission. However, mechanisms that link ABA and seed shattering remain elusive. In this study, we compared WR04-6 a shattering, and SN9816 non-shattering rice variety for genetic expression and ABA levels in the abscission zone (AZ) and the spikelet. Results : ABA content in WR04-6, particularly in AZ, was significantly higher than that in SN9816, and it increased remarkably prior to abscission. Transcriptomic analysis and qRT-PCR showed that the expression of NCED , the key gene in ABA biosynthesis, coincided with increased ABA content in AZ and increased significantly during the seed shattering process. Additionally, the expression of genes related biosynthesis and metabolism of IAA, GA, and ETH showed the greatest fold change. Phytohormone levels associated with ABA co-expression-prediction revealed a potential signal transduction network among plant hormones involved in regulating seed abscission. Conclusions: Altogether, our data strongly indicated that ABA contributes to seed shattering and appears to transiently cooperate with other hormones, triggering a hormone imbalance that leads to the downstream activation of AZ

scholarly journals SlSWEET15 exports sucrose from phloem and seed coat in tomato to supply carbon for fruit and seed development

2020 ◽  
Author(s):  
Han-Yu Ko ◽  
Li-Hsuan Ho ◽  
H. Ekkehard Neuhaus ◽  
Woei-Jiun Guo
Keyword(s):  
Seed Coat ◽  
Fruit Development ◽  
Molecular Mechanisms ◽  
Sucrose Transport ◽  
Vegetative Organs ◽  
Seed Filling ◽  
Carbon Supply ◽  
Seed Coats

ABSTRACTTomato, an important fruit crop worldwide, requires efficient sugar allocation for fruit development. However, molecular mechanisms for sugar import to fruits remain poorly understood. Expression of SWEET (Sugars Will Eventually be Exported Transporters) proteins is closely linked with hexose ratio in tomato fruits and may be involved in sugar allocation. Here, using quantitative PCR, we discovered that SlSWEET15 was highly expressed in developing fruits compared to vegetative organs. Based on in situ hybridization and GUS fusion analyses, SlSWEET15 proteins accumulated in vascular tissues and seed coats, major sites of sucrose unloading in fruits. Localizing SlSWEET15-GFP to the plasma membrane supported its putative role in apoplasmic sucrose unloading. The sucrose transport activity of SlSWEET15 was confirmed by complementary growth assays in a yeast mutant. Elimination of the SlSWEET15 function by CRISPR/cas9 gene editing significantly decreased average sizes and weights of fruits, with severe defects in seed filling and embryo development. Together, we confirmed the role of SlSWEET15 in mediating sucrose efflux from the releasing phloem to the fruit apoplasm and subsequent import into parenchyma cells during fruit development. Furthermore, SlSWEET15-mediated sucrose efflux was also required for sucrose unloading from the seed coat to the developing embryo.One-sentence SummarySlSWEET15, a specific sucrose uniporter in tomato, mediates apoplasmic sucrose unloading from releasing phloem cells and seed coat for carbon supply during fruit expansion and seed filling.

How do histone modifications contribute to transgenerational epigenetic inheritance in C. elegans?

2020 ◽  
Vol 48 (3) ◽  
pp. 1019-1034 ◽  
Author(s):  
Rachel M. Woodhouse ◽  
Alyson Ashe
Keyword(s):  
Histone Modifications ◽  
Molecular Mechanisms ◽  
Epigenetic Inheritance ◽  
Nematode Caenorhabditis Elegans ◽  
Histone Methyltransferases ◽  
Transgenerational Epigenetic Inheritance ◽  
C Elegans ◽  
Recent Developments ◽  
Gene Regulatory

Gene regulatory information can be inherited between generations in a phenomenon termed transgenerational epigenetic inheritance (TEI). While examples of TEI in many animals accumulate, the nematode Caenorhabditis elegans has proven particularly useful in investigating the underlying molecular mechanisms of this phenomenon. In C. elegans and other animals, the modification of histone proteins has emerged as a potential carrier and effector of transgenerational epigenetic information. In this review, we explore the contribution of histone modifications to TEI in C. elegans. We describe the role of repressive histone marks, histone methyltransferases, and associated chromatin factors in heritable gene silencing, and discuss recent developments and unanswered questions in how these factors integrate with other known TEI mechanisms. We also review the transgenerational effects of the manipulation of histone modifications on germline health and longevity.

Mesophyll conductance: the leaf corridors for photosynthesis

2020 ◽  
Vol 48 (2) ◽  
pp. 429-439 ◽  
Author(s):  
Jorge Gago ◽  
Danilo M. Daloso ◽  
Marc Carriquí ◽  
Miquel Nadal ◽  
Melanie Morales ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Main Role ◽  
Mesophyll Conductance ◽  
Future Studies ◽  
Cell Structures ◽  
Leaf Tissues ◽  
Change Framework ◽  
Chloroplast Stroma

Besides stomata, the photosynthetic CO2 pathway also involves the transport of CO2 from the sub-stomatal air spaces inside to the carboxylation sites in the chloroplast stroma, where Rubisco is located. This pathway is far to be a simple and direct way, formed by series of consecutive barriers that the CO2 should cross to be finally assimilated in photosynthesis, known as the mesophyll conductance (gm). Therefore, the gm reflects the pathway through different air, water and biophysical barriers within the leaf tissues and cell structures. Currently, it is known that gm can impose the same level of limitation (or even higher depending of the conditions) to photosynthesis than the wider known stomata or biochemistry. In this mini-review, we are focused on each of the gm determinants to summarize the current knowledge on the mechanisms driving gm from anatomical to metabolic and biochemical perspectives. Special attention deserve the latest studies demonstrating the importance of the molecular mechanisms driving anatomical traits as cell wall and the chloroplast surface exposed to the mesophyll airspaces (Sc/S) that significantly constrain gm. However, even considering these recent discoveries, still is poorly understood the mechanisms about signaling pathways linking the environment a/biotic stressors with gm responses. Thus, considering the main role of gm as a major driver of the CO2 availability at the carboxylation sites, future studies into these aspects will help us to understand photosynthesis responses in a global change framework.

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