Hye Lin Park

Purdue University | Purdue · Department of Botany and Plant Pathology

Citrus plants have diverse methoxyflavonoids including, chrysoeriol, isosakuranetin, and nobiletin. In plants, O -methyltransferases (OMTs) participate in the methylation of a vast array of secondary metabolites, including flavonoids, phenylpropanoids, and alkaloids. To identify functional OMTs involved in the formation of methoxyflavonoids, orange...

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 pathwa...

The 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 en...

The 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 deg...

Chalcone 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. Rice contains seven CHI family genes (OsCHIs). Molecu...

Significance Protein homeostasis is critical for the proper growth and development of organisms. In ethylene biosynthesis, the protein abundance of ACC synthases (ACS), the rate-limiting enzymes in ethylene biosynthesis, is critical to control ethylene production and is regulated in part through crosstalk with other phytohormones. However, the unde...

Methylation is a common structural modification that can alter and improve the biological activities of natural compounds. O-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 OMT gene...

Ethylene gas controls plant growth and stress responses. Ethylene-exposed dark-grown seedlings exhibit a dramatic growth reduction, yet the seedlings rapidly return to the basal growth rate when ethylene gas is removed. However, the underlying mechanism governing this remarkable reversible acclimation of dark-grown seedlings to ethylene remains eni...

: Chalcone synthase (CHS) is a key enzyme in the flavonoid pathway, participating in the production of phenolic phytoalexins. The rice genome contains 31 CHS family genes (OsCHSs). The molecular characterization of OsCHSs suggests that OsCHS8 and OsCHS24 belong in the bona fide CHSs, while the other members are categorized in the non-CHS group of t...

Soil salinity is a major production constrain for agricultural crops, especially in Oryza sativa (rice). Analyzing physiological effect and molecular mechanism under salt stress is key for developing stress-tolerant plants. Roots system has a major role in coping with the osmotic change impacted by salinity and few salt-stress-related transcriptome...

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 CAD and CAD-like genes, collectively called OsCADs. To elucidate the biochemical function of the OsCADs, OsCAD1, 2, 6,...

Cinnamoyl-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 CCR and CCR-like genes, collectively called OsCCRs. To elucidate the functions of OsCCRs, their phylogenetic re...

Although 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. Becau...

Rice 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 remarka...

The world population is rapidly growing and a corresponding increase in food production is needed to support this expansion. However, the increase in crop yield as a result of the Green revolution has reached a plateau. To further increase the yield potential, the upper limit of plant productivity has to be raised, which has prompted us to put more...

Rice 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 perfor...

Flavonoids are ubiquitous secondary metabolites in plants and possess a wide range of biological activities such as anti-oxidant, anti-microbial, and anti-cancer activities. As a food ingredient, flavonoids are also thought to have health-promoting and disease-preventing properties. Structural modifications of flavonoids can improve their biologica...

Nascent polypeptide associated complex (NAC) proteins bind to newly synthesized polypeptide chains from ribosome and are involved in various physiological processes. An in vitro pulldown assay demonstrated that the previously identified NAC protein interacts with phytochromes. Phytochrome-interacting NAC protein (PNAC) was expressed in the cytosol,...