Modulation of organic acids and sugar content in tomato fruits by an abscisic acid-regulated transcription factor

Abstract In flowering plants, repression of the seed maturation program is essential for the transition from the seed to the vegetative phase, but the underlying mechanisms remain poorly understood. The B3-domain protein VIVIPAROUS1/ABSCISIC ACID-INSENSITIVE3-LIKE 1 (VAL1) is involved in repressing the seed maturation program. Here we uncovered a molecular network triggered by the plant hormone brassinosteroid (BR) that inhibits the seed maturation program during the seed-to-seedling transition in Arabidopsis (Arabidopsis thaliana). val1-2 mutant seedlings treated with a BR biosynthesis inhibitor form embryonic structures, whereas BR signaling gain-of-function mutations rescue the embryonic structure trait. Furthermore, the BR-activated transcription factors BRI1-EMS-SUPPRESSOR 1 and BRASSINAZOLE-RESISTANT 1 bind directly to the promoter of AGAMOUS-LIKE15 (AGL15), which encodes a transcription factor involved in activating the seed maturation program, and suppress its expression. Genetic analysis indicated that BR signaling is epistatic to AGL15 and represses the seed maturation program by downregulating AGL15. Finally, we showed that the BR-mediated pathway functions synergistically with the VAL1/2-mediated pathway to ensure the full repression of the seed maturation program. Together, our work uncovered a mechanism underlying the suppression of the seed maturation program, shedding light on how BR promotes seedling growth.

Download Full-text

Natürliche Hemmstoffe von Keimung und Wachstum, I Ausarbeitung eines quantitativen Biotests und Anwendung auf Extrakte aus Spelzen von Avena sativa L. / Natural Inhibitors of Germination and Growth, I. Development of a Quantitative Biotest and Application upon Extracts from Husks of Avena sativa L.

Zeitschrift für Naturforschung C ◽

10.1515/znc-1982-0911 ◽

1982 ◽

Vol 37 (9) ◽

pp. 793-801 ◽

Cited By ~ 4

Author(s):

Rudolf Karl ◽

Wolfhart Rüdiger

Keyword(s):

Abscisic Acid ◽

Root Growth ◽

Organic Acids ◽

Avena Sativa ◽

Inhibitory Activity ◽

Lepidium Sativum ◽

Carbonic Acids ◽

Germination And Growth ◽

Natural Inhibitors ◽

Lepidium Sativum L

Extracts from oat husks inhibit germination of a variety of seeds including Avena sativa L., Sorghum spec., Phalleris spec., Raphanus spec., Amaranthus caudatus, Lepidium sativum L. A quantitative assay for this inhibition was developed on the basis of percentage of root growth of Avena in the presence of extracted material compared with root growth of water controls. Fractionation of the extracts revealed that about half of the total inhibitory activity was found in the fraction of free organic acids. The inhibition was not due to known inhibitors. Abscisic acid. was not found in this extract. Phenole carbonic acids were determined in the extract. Their concentration was too low to significantly contribute to the observed inhibitory activity.

Download Full-text

Ectopic expression of a conifer Abscisic Acid Insensitive3 transcription factor induces high-level synthesis of recombinant human α-l-iduronidase in transgenic tobacco leaves

Plant Molecular Biology ◽

10.1007/s11103-006-9122-y ◽

2007 ◽

Vol 63 (6) ◽

pp. 763-776 ◽

Cited By ~ 11

Author(s):

Allison R. Kermode ◽

Ying Zeng ◽

Xiaoke Hu ◽

Samantha Lauson ◽

Suzanne R. Abrams ◽

...

Keyword(s):

Transcription Factor ◽

Abscisic Acid ◽

Transgenic Tobacco ◽

Ectopic Expression ◽

High Level Synthesis ◽

Tobacco Leaves ◽

Abscisic Acid Insensitive3 ◽

High Level

Download Full-text

Accumulation of sugars and associated gene expression in highbush blueberries differ by cultivar, ripening stage, and storage temperature

Journal of Berry Research ◽

10.3233/jbr-210748 ◽

2021 ◽

pp. 1-17

Author(s):

Chau Thi Thu Nguyen ◽

Ji Hyun Lee ◽

Phu Tri Tran

Keyword(s):

Gene Expression ◽

Organic Acids ◽

Sensory Quality ◽

Sugar Content ◽

Postharvest Quality ◽

Ripening Stage ◽

Expression Levels ◽

Highbush Blueberries ◽

And Storage ◽

Gene Expression Levels

BACKGROUND: The sweetness of highbush blueberries is a sensory quality standard for consumers. Changes in metabolites and expression of associated genes induce variation in the sensory quality of blueberries. OBJECTIVE: This work investigated the ripening mechanism of blueberries by measuring changes in organic acids and sugar content as well as the gene expression levels associated with sugar accumulation, such as β amylase, invertase, sucrose phosphate synthase, and tonoplast monosaccharide transporter genes, before and after harvesting. METHODS: We used three different blueberry cultivars (Duke, Sierra, and Elizabeth) that we harvested at two ripening stages in a randomized complete block design and then kept at room temperature or 4°C for 7 days. The organic acids and sugar content were measured via HPLC, and gene expression levels were analyzed by qPCR. RESULTS: Cultivars, ripening stage, and storage conditions affected the synthesis of sugars and degradation of organic acids to determine the sweetness in blueberries and the expression of tagged genes and analyses of compounds involved in the metabolic mechanism. CONCLUSIONS: The results provide insights into the mechanism underlying the ripening and the postharvest quality. This study may support the selection of suitable blueberry cultivars that meet customer demand.

Download Full-text

The Halophyte Halostachys caspica AP2/ERF Transcription Factor HcTOE3 Positively Regulates Freezing Tolerance in Arabidopsis

Frontiers in Plant Science ◽

10.3389/fpls.2021.638788 ◽

2021 ◽

Vol 12 ◽

Author(s):

Fangliu Yin ◽

Youling Zeng ◽

Jieyun Ji ◽

Pengju Wang ◽

Yufang Zhang ◽

...

Keyword(s):

Transcription Factor ◽

Abscisic Acid ◽

Freezing Tolerance ◽

Critical Role ◽

Extreme Temperature ◽

Freezing Stress ◽

Antioxidant Enzyme Activities ◽

Transcription Factor Gene ◽

Factor Gene ◽

Halostachys Caspica

The APETALA2 (AP2) and ethylene-responsive element-binding factor (ERF) gene family is one of the largest plant-specific transcription factor gene families, which plays a critical role in plant development and evolution, as well as response to various stresses. The TARGET OF EAT3 (TOE3) gene is derived from Halostachys caspica and belongs to the AP2 subfamily with two AP2 DNA-binding domains. Currently, AP2 family mainly plays crucial roles in plant growth and evolution, yet there are few reports about the role of AP2 in abiotic stress tolerance. Here, we report HcTOE3, a new cold-regulated transcription factor gene, which has an important contribution to freezing tolerance. The main results showed that the expression of HcTOE3 in the H. caspica assimilating branches was strongly induced by different abiotic stresses, including high salinity, drought, and extreme temperature (heat, chilling, and freezing), as well as abscisic acid and methyl viologen treatments. Overexpressing HcTOE3 gene (OE) induced transgenic Arabidopsis plant tolerance to freezing stress. Under freezing treatment, the OE lines showed lower content of malondialdehyde and electrolyte leakage and less accumulation of reactive oxygen species compared with the wild type. However, the survival rates, antioxidant enzyme activities, and contents of osmotic adjustment substance proline were enhanced in transgenic plants. Additionally, the OE lines increased freezing tolerance by up-regulating the transcription level of cold responsive genes (CBF1, CBF2, COR15, COR47, KIN1, and RD29A) and abscisic acid signal transduction pathway genes (ABI1, ABI2, ABI5, and RAB18). Our results suggested that HcTOE3 positively regulated freezing stress and has a great potential as a candidate gene to improve plant freezing tolerance.

Download Full-text