• Molecules and Cells
• /
• v.41 no.4
• /
• pp.311-319
• /
• 2018

The gaseous hormone ethylene influences many aspects of plant growth, development, and responses to a variety of stresses. The biosynthesis of ethylene is tightly regulated by various internal and external stimuli, and the primary target of the regulation is the enzyme 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (ACS), which catalyzes the rate-limiting step of ethylene biosynthesis. We have previously demonstrated that the regulation of ethylene biosynthesis is a common feature of most of the phytohormones in etiolated Arabidopsis seedlings via the modulation of the protein stability of ACS. Here, we show that various phytohormones also regulate ethylene biosynthesis from etiolated rice seedlings in a similar manner to those in Arabidopsis. Cytokinin, brassinosteroids, and gibberellic acid increase ethylene biosynthesis without changing the transcript levels of neither OsACS nor ACC oxidases (OsACO), a family of enzymes catalyzing the final step of the ethylene biosynthetic pathway. Likewise, salicylic acid and abscisic acid do not alter the gene expression of OsACS, but both hormones downregulate the transcript levels of a subset of ACO genes, resulting in a decrease in ethylene biosynthesis. In addition, we show that the treatment of the phytohormones results in distinct etiolated seedling phenotypes, some of which resemble ethylene-responsive phenotypes, while others display ethylene-independent morphologies, indicating a complicated hormone crosstalk in rice. Together, our study brings a new insight into crosstalk between ethylene biosynthesis and other phytohormones, and provides evidence that rice ethylene biosynthesis could be regulated by the post-transcriptional regulation of ACS proteins.

• Korean journal of applied entomology
• /
• v.61 no.1
• /
• pp.15-28
• /
• 2022

Neuropeptides produced in neurosecretory cells are the largest group of insect hormones. They regulate various physiological functions, such as fat body homeostasis, feeding, digestion, excretion, circulation, reproduction, metamorphosis, and behavior throughout all life stages. The PRXamide peptide family (X, a variable amino acid) is a well-characterized neuropeptide component with a common amino acid sequence, PRXamide (NH₂), at the C-terminal end conserved across Insecta. The PRXamide peptides are classified into three subfamilies, each having diverse biological roles in insects: (1) pyrokinin (PK) includes the pheromone biosynthesis activating neuropeptide (PBAN) and the diapause hormone (DH), (2) the capability (CAPA) peptides, and (3) the ecdysis-triggering hormone (ETH). PBAN as a member of PK subfamily was first identified to stimulate pheromone biosynthesis in moths three decades ago. Since then, PBAN peptides have been extensively studied by various research groups from a broad spectrum of arthropods. In this paper, we briefly review insect PBAN molecules with emphasis on gene structure and expression, signal transduction, physiological mechanism in sex pheromone biosynthesis, and application for pest management.

• Advances in Traditional Medicine
• /
• v.1 no.2
• /
• pp.6-13
• /
• 2000

Melanin is specifically produced in melanocytes. The pathway for melanin biosynthesis is mainly controlled by tyrosinase. To estimate the inhibitory effect of melanin biosynthesis from 31 medicinal plants extracts, we tested the inhibitory effects of the tyrosinase promoter on B16 mouse melanoma cells. The result of this study demonstrated that Mori Radicis Cortex and Castena Fractus extracts only in tested medicinal plant extracts have high inhibitory effects on tyrosinase promoters with very low cytotoxicity on B16 mouse melanoma cells. Therefore, extracts of Mori Radicis Cortex and Castena Fractus were evaluated as very effective negative regulators of tyrosinase gene expression.

• The Plant Pathology Journal
• /
• v.40 no.2
• /
• pp.99-105
• /
• 2024

Land plants produce glucose (C₆H₁₂O₂) through photosynthesis by utilizing carbon dioxide (CO₂), water (H₂O), and light energy. Glucose can be stored in various polysaccharide forms for later use (e.g., sucrose in fruit, amylose in plastids), used to create cellulose, the primary structural component of cell walls, and immediately metabolized to generate cellular energy, adenosine triphosphate, through a series of respiratory pathways including glycolysis, the tricarboxylic acid cycle, and oxidative phosphorylation. Additionally, plants must metabolize glucose into amino acids, nucleotides, and various plant hormones, which are crucial for regulating many aspects of plant physiology. This review will summarize the biosynthesis of different plant hormones, such as auxin, salicylic acid, gibberellins, cytokinins, ethylene, and abscisic acid, in relation to glucose metabolism.

• BMB Reports
• /
• v.32 no.1
• /
• pp.72-75
• /
• 1999

In an effort to understand the function of the eryBVII gene in the erythromycin biosynthetic gene cluster, we overexpressed the eryBVII gene in E. coli and TDP-6-deoxy-L-threo-D-glycero-4-hexulose was used as a substrate of the overexpressed EryBVII enzyme. The enzymatic reaction product was chemically modified by reduction and peracetylation. Structural analysis of the derivatized enzymatic products by GC-Mass Spectrophotometry indicated that TDP-6-deoxy-L-threo-D-glycero-4-hexulose could be converted into its epimer by EryBVII enzyme. Based on this result, TDP-6-deoxy-L-threo-D-glycero-4-hexulose was indeed the substrate of EryBVII enzyme and the function of the eryBVII gene was confirmed.

• Korean Journal of Breeding Science
• /
• v.43 no.1
• /
• pp.1-13
• /
• 2011

Low temperature stress is one of the major negative factors affecting vegetative and reproductive growth of rice. To better understand responses of rice plants to low temperature we analyzed transcriptome expression patterns in glumous flower of cold-tolerant japonica rice variety, Stejaree45, and cold-susceptible variety, HR19621-AC6 at booting stage under cold water irrigation. A total of 2,411 probes were differentially expressed by low temperature in glumous flowers of the two varieties. Some important genes involved in hormone biosynthesis showed variety-specific regulation. Expression of GA20ox3 and GA2ox, among the genes involved in GA biosynthesis, was regulated differentially in the two varieties. Among the genes involved in IAA biosynthesis, YUCCA1 and TAA1:1 showed variety-specific regulation. Among the genes involved in cytokinin biosynthsis and signaling, expression of LOG, HK1 and HK3 was significantly down-regulated only in the cold-susceptible variety. Among the genes involved in ABA biosynthesis, NSY and AAO3 were down-regulated only in the cold-tolerant variety. In general, genes involved in GA, IAA and cytokinin biosynthesis responded to cold temperature in such a way that capacity of those bioactive hormones is maintained at relatively higher levels under cold temperature in the cold-tolerant variety, which can help minimize cold stress imposed to developing reproductive organs in the cold-tolerant variety.

• Journal of Ginseng Research
• /
• v.12 no.2
• /
• pp.104-113
• /
• 1988

Effect of the purified ginsenoside $-Rb_1$ and $-Rb_2$ on LDL receptor biosynthesis of CHO cell cultured in a high cholesterol medium was investigated . Cholesterol uptake by CHO cell cultured in a medium containing various amounts of cholesterol was traced and found that the cholesterol uptake was proportional to the concentration of cholesterol in the medium, and the population of LDL receptors were proportionally decreased as the increasing cholesterol level in the cell. However, when the CHO cells were cultured in the medium containing ginsenosides, no significant decrease of LDL receptor population occured. The biosynthesis of protein and RNA of the above cells was higher than that of CHO cells cultured in the absence of the ginsenosides, suggesting that the ginsenosides might stimulate LDL receptor bio-synthesis. It was also observed that the ginsenosides stimulated the biosynthesis of estradiol and progesterone from cholesterol in the CHO cell. From the above results, it seemed that the ginsenosides lowers the cholesterol level by stimulating the cholesterol metablism including steroid hormone biosynthesis, resulting in the lowering of inhibitory action of cholesterol on LDL receptor biosynthesis.

• Journal of Applied Biological Chemistry
• /
• v.63 no.1
• /
• pp.89-93
• /
• 2020

In this study, the efficacy of melanoma cell B16F10 was investigated using the Korean native plant Oplismenus undulatifolius (OU). First, the cell viability of the extract was more than 90% when treated with 15 ㎍/mL of phenolics from OU. The results showed that melanin biosynthesis and cellular tyrosinase synthesis were inhibited by treatment with α-melanocyte-stimulating hormone-stimulated mouse melanoma cell B16F10 at a concentration of 15 ㎍/mL of phenolics for cell-line efficacy. The expression of tyrosinase, tyrosinase-related protein (TRP)-1, TRP-2, and microphthalmia transcription factor (MITF) protein was confirmed by western blot to investigate the effect of phenolics from OU on melanin biosynthesis. When treated with phenolics from OU 15 ㎍/mL, tyrosinase, TRP-1, TRP-2, and MITF decreased the protein expression level. In particular, tyrosinase, TRP-1, and MITF inhibited the production amount to a level similar to that of the non-treated normal group, indicating that the effect was excellent. Therefore, phenolics from OU acts as an inhibitor of tyrosinase, TRP-1, TRP-2, and its transcription factor MITF, and participates in melanin biosynthesis mechanism. These results suggested the potential for development as a material.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.22 no.3
• /
• pp.649-653
• /
• 2008

The aqueous extract from Asiasari radix (AEAR) was used to investigate the effect of ${\alpha}$-melanocyte stimulating hormone induced melanogenesis in B16F10 mouse melnoma cells. The treatment with AEAR at the 1.0 and 2.0 mg/ml level significantly inhibited the biosynthesis of melanin without changes of cell growth and morphology compared with untreated control. The AEAR-treated cells at the 2.0 mg/ml level were more efficient than commercial arbutin at 0.1 mg/ml. The tyrosinase activity also significantly decreased in AEAR-treated cells at the 1.0 and 2.0 mg/ml level. The Western analyses confirmed the slightly decreased expression of tyrosinase by AEAR treatment. These results indicate that AEAR may contribute to the inhibition of melanin biosynthesis through regulating tyrosinase activity and expression and serve as a new candidate in the design of new skin-whitening or therapeutic agents.

• Journal of Plant Biotechnology
• /
• v.47 no.3
• /
• pp.194-202
• /
• 2020

The sweetpotatoes (Ipomoea batatas) generate adventitious roots (ARs) from cut stems that develop into storage roots and make for an important means of propagation. However, few studies have investigated the hormones involved in AR development in sweetpotato. In this study, the expression patterns of hormone-related genes involved in AR formation were identified using the transcriptome data. RNA-seq data from stems grown for 0 and 3 days after cutting were analyzed. In addition, hormone-related genes were identified among differentially expressed genes (DEGs) and filtered genes, and cluster analysis was used to characterize expression patterns by function. Most hormone-related regulated genes expressed 3 days after growing the cut stems were abscisic acid (ABA)-related genes, followed by ethylene- and auxin-related genes. For ABA, the biosynthesis genes (including genes annotated to NINE-CIS-EPOXYCAROTENOID DIOXYGENASE 3 (NCED3)) and signal transduction and perception genes (including genes annotated to PROTEIN PHOSPHATASE 2Cs (PP2Cs)) tended to decrease. Expression patterns of auxin- and ethylene-related genes differed by function. These results suggest that ABA, auxin, and ethylene genes are involved in AR formation and that they may be regulated in a hormone function-dependent manner. These results contribute to the identification of hormone functions during AR formation and may contribute to understanding the mechanism of AR formation in the sweetpotato.