Protein-protein interactions play a crucial role in driving cellular processes and enabling appropriate physiological responses in organisms. The plant hormone ethylene signaling pathway is complex and regulated by the spatiotemporal regulation of its signaling molecules. Constitutive Triple Response 1 (CTR1), a key negative regulator of the pathway, regulates the function of Ethylene-Insensitive 2 (EIN2), a positive regulator of ethylene signaling, at the endoplasmic reticulum (ER) through phosphorylation.
View Article and Find Full Text PDFThe phytohormone ethylene controls plant growth and stress responses. Ethylene-exposed dark-grown Arabidopsis seedlings exhibit dramatic growth reduction, yet the seedlings rapidly return to the basal growth rate when ethylene gas is removed. However, the underlying mechanism governing this acclimation of dark-grown seedlings to ethylene remains enigmatic.
View Article and Find Full Text PDFThe precise regulation of the homeostasis of the cellular proteome is critical for the appropriate growth and development of plants. It also allows the plants to respond to various environmental stresses, by modulating their biochemical and physiological aspects in a timely manner. Ubiquitination of cellular proteins is one of the major protein degradation routes for maintaining cellular protein homeostasis, and ubiquitin E3 ligases, components of ubiquitin ligase complexes, play an important role in the selective degradation of target proteins via substrate-specific interactions.
View Article and Find Full Text PDFChalcone isomerase (CHI) is a key enzyme in flavonoid biosynthesis. In plants, CHIs occur in multigene families, and they are divided into four types, types I-IV. Type I and II CHIs are bona fide CHIs with CHI activity, and type III and IV CHIs are non-catalytic members with different functions.
View Article and Find Full Text PDFEthylene influences plant growth, development, and stress responses via crosstalk with other phytohormones; however, the underlying molecular mechanisms are still unclear. Here, we describe a mechanistic link between the brassinosteroid (BR) and ethylene biosynthesis, which regulates cellular protein homeostasis and stress responses. We demonstrate that as a scaffold, 1-aminocyclopropane-1-carboxylic acid (ACC) synthases (ACS), a rate-limiting enzyme in ethylene biosynthesis, promote the interaction between Seven-in-Absentia of (SINAT), a RING-domain containing E3 ligase involved in stress response, and ETHYLENE OVERPRODUCER 1 (ETO1) and ETO1-like (EOL) proteins, the E3 ligase adaptors that target a subset of ACS isoforms.
View Article and Find Full Text PDFMethylation is a common structural modification that can alter and improve the biological activities of natural compounds. -Methyltransferases (OMTs) catalyze the methylation of a wide array of secondary metabolites, including flavonoids, and are potentially useful tools for the biotechnological production of valuable natural products. An gene () was isolated from perilla leaves as a putative flavonoid OMT (FOMT).
View Article and Find Full Text PDFChalcone synthase (CHS) is a key enzyme in the flavonoid pathway, participating in the production of phenolic phytoalexins. The rice genome contains 31 family genes (s). The molecular characterization of s suggests that and belong in the bona fide CHSs, while the other members are categorized in the non-CHS group of type III polyketide synthases (PKSs).
View Article and Find Full Text PDFBackground/aims: The mucosal healing process after endoscopic submucosal dissection (ESD) is mostly scarring change (flat type), but a protruded lesion is occasionally found. We investigated the factors influencing the mucosal healing process, such as the flat and protruded types.
Methods: A total of 2,096 ESD cases were performed from February 2005 to December 2013, and 1,757 underwent follow-up endoscopy after 3 months to check the healing type of the ulceration.
Cinnamyl alcohol dehydrogenase (CAD) is involved in the final step of the phenylpropanod pathway, catalyzing the NADPH-dependent reduction of hydroxy-cinnamaldehydes into the corresponding alcohols. The rice genome contains twelve and genes, collectively called s. To elucidate the biochemical function of the s, , , , and , which are highly expressed in rice, were cloned from rice tissues.
View Article and Find Full Text PDFCinnamoyl-CoA reductase (CCR) is the first committed enzyme in the monolignol pathway for lignin biosynthesis and catalyzes the conversion of hydroxycinnamoyl-CoAs into hydroxycinnamaldehydes. In the rice genome, 33 genes are annotated as and genes, collectively called s. To elucidate the functions of s, their phylogenetic relationships, expression patterns at the transcription levels and biochemical characteristics were thoroughly analyzed.
View Article and Find Full Text PDFAlthough they are less abundant in nature, methoxyflavonoids have distinct physicochemical and pharmacological properties compared to common nonmethylated flavonoids. Thus, enzymatic conversion and biotransformation using genetically engineered microorganisms of flavonoids have been attempted for the efficient production of methoxyflavonoids. Because of their regiospecificity, more than two flavonoid O-methyltransferases (FOMTs) and enzyme reactions are required to biosynthesize di(or poly)-methoxyflavonoids.
View Article and Find Full Text PDFA fixed dose regimen for tyrosine kinase inhibitors (TKIs) is postulated to be responsible for variable safety outcomes in the treatment of chronic myelogenous leukemia (CML). The objective of this study was to explore an optimal dosing regimen for a TKI, radotinib, to improve its safety profile. Clinical data were obtained from a Phase 2 study of fixed-dose radotinib in 77 Asian patients with CML.
View Article and Find Full Text PDFRice produces a wide array of phytoalexins in response to pathogen attacks and UV-irradiation. Except for the flavonoid sakuranetin, most phytoalexins identified in rice are diterpenoid compounds. Analysis of phenolic-enriched fractions from UV-treated rice leaves showed that several phenolic compounds in addition to sakuranetin accumulated remarkably in rice leaves.
View Article and Find Full Text PDFRadotinib (IY5511HCL), a novel and selective BCR-ABL1 tyrosine kinase inhibitor, has shown pre-clinical and phase I activity and safety in chronic myeloid leukemia. This phase II study investigated the efficacy and safety of radotinib in Philadelphia chromosome-positive chronic phase-chronic myeloid leukemia patients with resistance and/or intolerance to BCR-ABL1 tyrosine kinase inhibitors. Patients received radotinib 400 mg twice daily for 12 cycles based on results from the phase I trial.
View Article and Find Full Text PDFRice produces diterpenoid and flavonoid phytoalexins for defense against pathogen attack. The production of phytoalexins in rice is also induced by UV-irradiation. To understand the metabolic networks involved in UV-induced phytoalexin biosynthesis and their regulation, phytochemical and transcriptomic analyses of UV-treated rice leaves were performed.
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