Plants must effectively defend against biotic and abiotic stresses to survive in nature. However, this defense is costly and is often accompanied by significant growth inhibition. How plants coordinate the fluctuating growth-defense dynamics is not well understood and remains a fundamental question. Jasmonate (JA) and gibberellic acid (GA) are important plant hormones that mediate defense and growth, respectively. Binding of bioactive JA or GA ligands to cognate receptors leads to proteasomedependent degradation of specific transcriptional repressors (the JAZ or DELLA family of proteins), which, at the resting state, represses cognate transcription factors involved in defense (e.g., MYCs) or growth [e.g. phytochrome interacting factors (PIFs)]. In this study, we found that the coi1 JA receptor mutants of rice (a domesticated monocot crop) and Arabidopsis (a model dicot plant) both exhibit hallmark phenotypes of GA-hypersensitive mutants. JA delays GA-mediated DELLA protein degradation, and the della mutant is less sensitive to JA for growth inhibition. Overexpression of a selected group of JAZ repressors in Arabidopsis plants partially phenocopies GA-associated phenotypes of the coi1 mutant, and JAZ9 inhibits RGA (a DELLA protein) interaction with transcription factor PIF3. Importantly, the pif quadruple (pifq) mutant no longer responds to JA-induced growth inhibition, and overexpression of PIF3 could partially overcome JA-induced growth inhibition. Thus, a molecular cascade involving the COI1-JAZ-DELLA-PIF signaling module, by which angiosperm plants prioritize JA-mediated defense over growth, has been elucidated. disease resistance | plant growth | plant immunity | light response | plant defense S essile plants have evolved a dynamic regulatory network to adapt to the daily and seasonally fluctuating environment. Jasmonate (JA) is a lipid-derived plant hormone that regulates developmental processes, including pollen development, tendril coiling, fruit ripening and senescence, as well as response to biotic and abiotic stress (1-3). The F-box protein coronatine insensitive 1 (COI1), a component of the SCF E3 ubiquitin ligase, has been identified as a principal component of a receptor of JA in Arabidopsis and other plants (4-7), and the JA ZIMdomain (JAZ) family proteins are key regulators of JA signaling that repress transcription of JA-responsive genes through interaction with transcription factors, such as MYC2 (8-10). This transcriptional repression requires novel interactor of JAZ (NINJA) and TOPLESS corepressor proteins (11). Bioactive JA, the jasmonoyl-isoleucine conjugate, promotes physical interaction between COI1 and JAZ proteins that results in degradation of JAZs by the 26S proteasome, leading to initiation of JA responses (9, 10). Therefore, the SCF COI1 -JAZ protein complex acts as a core site of JA perception. As a regulatory loop, JA also activates JAZ gene transcription, leading to the down-regulation of JA action and the dynamic nature of JA response (12).Gibberellic acids (GAs) are plant growth...

A highly efficient visible-light-driven photocatalyst is urgently necessary for photocatalytic hydrogen generation through water splitting. Herein, ZnIn S hierarchical architectures assembled as ultrathin nanosheets were synthesized by a facile one-pot polyol approach. Subsequently, the two-dimensional-network-like MoSe was successfully hybridized with ZnIn S by taking advantage of their analogous intrinsic layered morphologies. The noble-metal-free ZnIn S /MoSe heterostructures show enhanced photocatalytic H evolution compared to pure ZnIn S . It is noteworthy that the optimum nanocomposite of ZnIn S /2 % MoSe photocatalyst displays a high H generation rate of 2228 μmol g h and an apparent quantum yield (AQY) of 21.39 % at 420 nm. This study presents an unprecedented ZnIn S /MoSe metal-sulfide-metal-selenide hybrid system for H evolution. Importantly, the present efficient hybridization strategy reveals the potential of hierarchical nanoarchitectures for a multitude of energy storage and solar energy conversion applications.

Metal-and solvent-free industrial-quality graphene oxide (IQGO)-based highly efficient carbocatalytic system has been developed for the synthesis of β-ketoenamines. Initially, physicochemical properties of IQGO are briefly discussed by means of various microscopic and spectroscopic techniques. The present system accessed a wide range of substrates to yield β-ketoenamines in an excellent yield (86−100%) with 100% selectivity. Catalytic activity of IQGO is compared with other carbon materials such as carbon nanotubes, carbon nanofibers, and graphene nanoplatelets. Cost effective recovery, high level reusability, chemoselective nature, possible scale reaction, and sustainability of IQGO are demonstrated. Based upon experimental results and earlier reports, possible reaction mechanism has been proposed for the synthesis of β-ketoenamines.

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