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Autophagy is critical for plant defense against necrotrophic pathogens, which causes serious yield loss on crops. However, the post-translational regulatory mechanisms of autophagy pathway in plant resistance against necrotrophs remain poorly understood. In this study, we report that phosphorylation modification on ATG18a, a key regulator of autophagosome formation in Arabidopsis thaliana, constitutes a post-translation regulation of autophagy, which attenuates plant resistance against necrotrophic pathogens. We found that phosphorylation of ATG18a suppresses autophagosome formation and its subsequent delivery into the vacuole, which results in reduced autophagy activity and compromised plant resistance against Botrytis cinerea. In contrast, overexpression of ATG18a dephosphorylation-mimic form increases the accumulation of autophagosomes and complements the plant resistance of atg18a mutant against B. cinerea. Moreover, BAK1, a key regulator in plant resistance, was identified to physically interact with and phosphorylate ATG18a. Mutation of BAK1 blocks ATG18a phosphorylation at four of the five detected phosphorylation sites after B. cinerea infection and strongly activates autophagy, leading to enhanced resistance against B. cinerea. Collectively, the identification of functional phosphorylation sites on ATG18a and the corresponding kinase BAK1 unveiled how plant regulates autophagy during resistance against necrotrophic pathogens. Abbreviations: 35s: the cauliflower mosaic virus 35s promoter; A. thaliana: Arabidopsis thaliana; A. brassicicola: Alternaria brassicicola; ABA: abscisic acid; ATG: autophagy-related; ATG18a: autophagy-related protein 18a in A. thaliana; ATG8a: autophagy-related protein 8a in A. thaliana; ATG8–PE: ATG8 conjugated with PE; B. cinerea: Botrytis cinerea; BAK1: Brassinosteroid insensitive 1-associated receptor kinase1 in A. thaliana; BiFC: biomolecular fluorescence complementation; BIK1: Botrytis-insensitive kinase 1 in A. thaliana; BKK1: BAK1-like 1 in A. thaliana; BR: brassinosteroid; Co-IP: coimmunoprecipitation; dai: days after inoculation; DAMPs: damage-associated molecular patterns; E. coli: Escherochia coli; ER: endoplasmic reticulum; ETI: effector-triggered immunity; GFP: green fluorescent protein; HA: hemagglutinin; IP: immunoprecipitation; LC-MS/MS: liquid chromatography-tandem mass spectrometry; LCI: luciferase complementation imaging; MPK3: mitogen-activated protein kinase 3 in A. thaliana; MPK4: mitogen-activated protein kinase 4 in A. thaliana; MPK6: mitogen-activated protein kinase 6 in A. thaliana; N. benthamiana: Nicotiana benthamiana; NES: nuclear export sequence; PAMP: pathogen-associated molecular pattern; PCR: polymerase chain reaction; PE: phosphatidylethanolamine; PRR: pattern recognition receptor; PtdIns(3,5)P(2:) phosphatidylinositol (3,5)-biphosphate; PtdIns3P: phosphatidylinositol 3-biphosphate; PTI: PAMP-triggered immunity; qRT-PCR: quantitative reverse transcription PCR; SnRK2.6: SNF1-related protein kinase 2.6 in A. thaliana; TORC1: the rapamycin-sensitive Tor complex1; TRAF: tumor necrosis factor receptor-associated factor; WT: wild type plant; Yc: C-terminal fragment of YFP; YFP: yellow fluorescent protein; Yn: N-terminal fragment of YFP

Chlorophytum comosum belongs to genus Chlorophytum of family Asparagaceae that has more than 215 species. it is among 120 plant species assayed for phytoremediation of pollutants from indoor air. It has the ability to remove formaldehyde, nitrogen dioxide, carbon oxide, ozone, benzene, toluene, cigarette smoke and ammonia. It also is an important Chinese tradition medicine material. Aim to get more information about its mitochondrial genome, we sequenced the complete mitochondrial genome of C. comosum. The length of mitochondrial genome was 950316 bp with 36 protein coding genes, 5 rRNAs and 21 tRNAs. Although it has the biggest mitochondrial genome, the total PCGs content were the second least. C. comosum had the most repeats sequence and it may effect the size of mitochondrial genome, but base the result we found that the quantity of repeats sequence could not have the positive correlation with the mitochondrial size. Compared with other 9 species , we found in the mitochondrial genome of C. comosum, there were at least one PCGs suffered from the positive selection after divergence. Finally, the result of phylogenetic showed that C. comosum did not have colesd relationship with other species.

Cochliobolus heterostrophus is the causal agent of southern corn leaf blight, a destructive disease on maize worldwide. However, how it regulates virulence on maize is still largely unknown. Here, we report that two copper transporter genes, ChCTR1 and ChCTR4, are required for its virulence. chctr1 and chctr4 mutants showed attenuated virulence on maize compared with the wild-type strain TM17 but development phenotypes of those mutants on media with or without infection-related stress agents were the same as the wild-type strain. Moreover, ChCTR1 and ChCTR4 play critical roles in appressorium formation and mutation of ChCTR1 or ChCTR4 suppresses the appressorium formation. Furthermore, copper-chelating agent ammonium tetrathiomolybdate suppressed the appressorium formation and virulence of C. heterostrophus on maize, whereas copper ions enhanced the appressorium formation and virulence on maize. The results indicate that copper ions are required for appressorium formation and virulence of C. heterostrophus on maize and are acquired from the environment by two copper transporters: ChCTR1 and ChCTR4.

The shale of the Lower Silurian Longmaxi Formation is an important gas-producing layer for shale gas development in southern China. This set of shale reservoir characteristics and shale gas development potential provide an important foundation for shale gas development. This study takes wellblock XN111 in the Sichuan Basin, China, as an example and uses X-ray diffraction (XRD), scanning electron microscopy (SEM), isothermal adsorption, and other techniques to analyze the shale reservoir characteristics of the Lower Silurian Longmaxi Formation. The results show that the Lower Silurian Longmaxi Formation was deposited in a deep-water shelf environment. During this period, carbonaceous shale and siliceous shale characterized by a high brittle mineral content ( quartz > 40 wt . % , carbonate mineral > 10 wt . % ) and a low clay mineral content (

A feasible label-free electrochemiluminescence (ECL) aptasensor that uses an Au-nanoparticle-functionalized g-C3N4 nanohybrid (Au-g-C3N4 NH) as the luminophore was constructed for highly sensitive acetylcholinesterase (AChE) detection. The sensor was fabricated by successively modifying a glassy carbon electrode with Au-g-C3N4 NH and thiol-modified AChE-specific aptamers. In the presence of AChE, the ECL signal decreased significantly, because AChE could hydrolyze the substrate acetylthiocholine to generate acetic acid, which could react with the co-reactant triethylamine (Et3N), leading to evident consumption of the co-reactant. The ECL response of the aptasensor was linearly proportional to the concentration of AChE ranging from 0.1 pg/mL to 10 ng/mL, with a detection limit of 42.3 fg/mL (S/N=3). This novel ECL sensing strategy demonstrated a highly sensitive and selective method for AChE detection and was expected to possess potential applications in clinical diagnosis and biomedical technology.