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Summary: Plants employ an array of intricate and hierarchical signaling cascades to perceive and transduce informational cues to synchronize and tailor adaptive responses. Systemic stress response (SSR) is a recognized complex signaling and response network quintessential to plant's local and distal responses to environmental triggers; however, the identity of the initiating signals has remained fragmented.Here, we show that both biotic (aphids and viral pathogens) and abiotic (high light and wounding) stresses induce accumulation of the plastidial‐retrograde‐signaling metabolite methylerythritol cyclodiphosphate (MEcPP), leading to reduction of the phytohormone auxin and the subsequent decreased expression of the phosphatase PP2C.D1.This enables phosphorylation of mitogen‐activated protein kinases 3/6 and the consequential induction of the downstream events ultimately, resulting in biosynthesis of the two SSR priming metabolites pipecolic acid and N‐hydroxy‐pipecolic acid.This work identifies plastids as a major initiation site, and the plastidial retrograde signal MEcPP as an initiator of a multicomponent signaling cascade potentiating the biosynthesis of SSR activators, in response to biotic and abiotic triggers. [ABSTRACT FROM AUTHOR]

BACKGROUND The silkworm pupae of Bombyx mori L. are considered to be a valuable unsaturated fatty acids (UFAs) resource. Enzymatic transesterification, which can produce structured lipids (SLs), is regarded as a desirable approach to utilize this resource, but requires long reaction time. A method to reduce the reaction time and obtain novel SLs is thus desirable. Hence, microwave irradiation was employed to reduce the reaction time and obtain novel SLs. In addition, high‐performance liquid chromatography with an evaporative light scattering detector was employed to investigate the contribution of the fatty acids (FAs) after microwave irradiation. RESULTS: One hour was required for a 1:5 substrate ratio of silkworm pupae oil (SPO):oleic acid (OA) using a solvent‐free system catalysed by Lipozyme RM IM (7%) at 60 °C with microwave irradiation at 50 W to obtain the novel SLs. The relative content of polyunsaturated FAs glyceride increased from 51.1% to 81.0%, and the relative content of glycerol trioleate (OOO) in SPO obtained in the microwave reactor was twice as high as that in the shaker reactor. In addition, the relative content of OA was increased from 3.9% to 35.8% in total compared with the products from the shaker reactor. Furthermore, the changes of α‐helix relative content of Lipozyme RM IM were observed after the reaction under the microwave irradiation. CONCLUSION: The results indicated that variations in the FA distribution of enzymatic transesterification reactions caused by microwave irradiation could aid the addition of OA and enrichment of UFAs. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: The preharvest application of Ca‐containing foliar fertilizers can reduce the incidence of bitter pit (BP) in apples and improve fruit quality by increasing the Ca content and decreasing both the N content and the N/Ca ratio in fruits. In this study, we aimed to investigate the control efficacy of Ca‐containing fertilizers on the incidence of BP and their effects on the Ca and N contents in bagged ‘Fuji’ apples by spraying foliar fertilizer containing calcium chloride (CaCl2), calcium nitrate [Ca(NO3)2] or calcium formate [Ca(HCOO)2] at an early stage, five days after full bloom (DAFB) and 40 DAFB, and at a late stage, 80 DAFB and 125 DAFB. RESULTS: The incidences of BP were reduced significantly by 43.2–73.0%, and the efficacy of spraying at an early stage was significantly higher than that of spraying at a late stage. The Ca content of bagged apple fruits increased whereas the N content and N/Ca ratio decreased after spraying Ca‐containing foliar fertilizers; however, the Ca content, N content and N/Ca ratio of apple leaves were differentially influenced. CONCLUSION: Foliar fertilizer containing CaCl2, Ca(NO3)2 or Ca(HCOO)2 can be used at an early stage to control BP in apple and improve the quality of bagged apple fruits. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

To maintain homeostasis in the face of intrinsic and extrinsic insults, cells have evolved elaborate quality control networks to resolve damage at multiple levels. Interorganellar communication is a key requirement for this maintenance, however the underlying mechanisms of this communication have remained an enigma. Here we integrate the outcome of transcriptomic, proteomic, and metabolomics analyses of genotypes including ceh1, a mutant with constitutively elevated levels of both the stress-specific plastidial retrograde signaling metabolite methyl -erythritol cyclodi phosphate (MEcPP) and the defense hormone salicylic acid (SA), as well as the high MEcPP but SA deficient genotype ceh1/ eds16, along with corresponding controls. Integration of multi-omic analyses enabled us to delineate the function of MEcPP from SA, and expose the compartmentalized role of this retrograde signaling metabolite in induction of distinct but interdependent signaling cascades instrumental in adaptive responses. Specifically, here we identify strata of MEcPP-sensitive stress-response cascades, among which we focus on selected pathways including organelle-specific regulation of jasmonate biosynthesis; simultaneous induction of synthesis and breakdown of SA; and MEcPP-mediated alteration of cellular redox status in particular glutathione redox balance. Collectively, these integrated multi-omic analyses provided a vehicle to gain an in-depth knowledge of genome-metabolism interactions, and to further probe the extent of these interactions and delineate their functional contributions. Through this approach we were able to pinpoint stress-mediated transcriptional and metabolic signatures and identify the downstream processes modulated by the independent or overlapping functions of MEcPP and SA in adaptive responses. [ABSTRACT FROM AUTHOR]

The reaction can be scaled up. [ABSTRACT FROM AUTHOR]