基于模拟–优化模式的梯级水库群突发水污染事件应急调度研究

根据突发水污染事件特征及相关影响因素,在水动力模型、水质模型的基础上,建立了基于模拟–优化模式的梯级水库群突发水污染事件应急调度优化模型。以清江中下游为例,采用改进的NSGA-Ⅱ算法,对水布垭–隔河岩–高坝洲梯级水库群应急调度优化模型的决策变量（应急调度函数中的控制变量）进行多目标优化,得到了Pareto最优解集及相应的Pareto前沿,并探讨了水库群联合调度在应对突发性水污染事件的合理性与有效性。结果表明,在水位、库容允许的情况下,优先调用距离污染源较近的或与被污染河段直接相连的水库,启动应急调度最多可使污染物浓度达标时间减少80.4%。根据优化结果分析了应急调度过程中损失的电能与污染物达标所用时间之间的竞争关系,并定量模拟了突发水污染事件中污染物浓度的沿程变化与随时间变化的过程。

Dual function of Arabidopsis A TAF1 in abiotic and biotic stress responses

NAC family genes encode plant-specific transcription factors involved in diverse biological processes. In this study, the Arabidopsis NAC gene ATAF1 was found to be induced by drought, high-salinity, abscisic acid （ABA）, methyl jasmonate, mechanical wounding, and Botrytis cinerea infection. Significant induction of ATAF1 was found in an ABA-deficient mutant aba2 subjected to drought or high salinity, revealing an ABA-independent mechanism of expression. Arabidopsis ATAFl-overexpression lines displayed many altered phenotypes, including dwarfism and short primary roots. Furthermore, in vivo experiments indicate that ATAF1 is a bonafide regulator modulating plant responses to many abiotic stresses and necrotrophic-pathogen infection. Overexpression of ATAF1 in Arabidopsis increased plant sensitivity to ABA, salt, and oxidative stresses. Especially, ATAF1 overexpression plants, but not mutant lines, showed remarkably enhanced plant tolerance to drought. Additionally, ATAF1 overexpression enhanced plant susceptibility to the necrotrophic pathogen B. cinerea, but did not alter disease symptoms caused by avirulent or virulent strains of P. syringae pv tomato DC3000. Transgenic plants overexpressing ATAF1 were hypersensitive to oxidative stress, suggesting that reactive oxygen intermediates may be related to ATAFl-mediated signaling in response to both pathogen and abiotic stresses.

Cretaceous-Cenozoic regional stress field evolution from borehole imaging in the southern Jinzhou area, western Liaoning, North China Craton

The Mesozoic Yanshanian Movement affected the tectonic evolution of the North China Craton(NCC).It is proposed that Mesozoic cratonic destruction peaked~125 Ma,possibly influenced by subduction of the western Pacific Plate beneath the Euro-Asian Plate in the Early Cretaceous.The southern Jinzhou area in the eastern block of the NCC preserves clues about the tectonic events and related geological resources.Studies of the regional stress field evolution from the Cretaceous to the Cenozoic can enhance our understanding of the tectonics and dynamics of the NCC.Borehole image logging technology was used to identify and collect attitudes of tensile fractures from 11 boreholes;these were subdivided into four groups according to dip direction,i.e.,NNW-SSE,NWW-SEE,W-E and NE-SW.The development of these fractures was controlled primarily by the regional tectonic stress field;temperature,lithology,and depth contributed to some extent.In 136-125 Ma in the Early Cretaceous,the area was characterized by extension that was oriented NNW-SSE and NWW-SEE;from 125-101 Ma the extension was oriented W-E;after 101 Ma it was NE-SW.This counterclockwise trend has persisted to the present,probably related to oblique subduction of the Pacific Plate,and is characterized by ongoing extension that is nearly N-S-oriented and NEE-SWW-oriented compression.

SIZ1-mediated SUMOylation of CPSF100 promotes plant thermomorphogenesis by controlling alternative polyadenylation

Under warm temperatures,plants adjust their morphologies for environmental adaption via precise gene expression regulation.However,the function and regulation of alternative polyadenylation(APA),an important fine-tuning of gene expression,remains unknown in plant thermomorphogenesis.In this study,we found that SUMOylation,a critical post-translational modification,is induced by a long-term treat-ment at warm temperatures via a SUMO ligase SIZ1 in Arabidopsis.Disruption of SIZ1 altered the global usage of polyadenylation signals and affected the APA dynamic of thermomorphogenesis-related genes.CPSF100,a key subunit of the CPSF complex for polyadenylation regulation,is SUMOylated by SIZ1.Importantly,we demonstrated that SUMOylation is essential for the function of CPSF1oo in genome-wide polyadenylation site choice during thermomorphogenesis.Further analyses revealed that the SUMO conjugation on CPSF100 attenuates its interaction with two isoforms of its partner CPSF30,increasing the nuclear accumulation of CPsF1oo for polyadenylation regulation.In summary,our study uncovers a regulatory mechanism of APA via SiZ1-mediated SUMOylation in plant thermomorpho-genesis.

煤岩学在炼焦配煤中的应用进展及优化配煤技术

科学合理的配煤技术对于焦化企业高质量发展至关重要,炼焦配煤技术的核心在于对原料煤煤质特性的深入认知。影响炼焦煤性质的主要因素包括变质程度、煤岩组成及第三成因因素,故煤岩学对炼焦配煤技术的研究与应用至关重要。本文论述了经验配煤、煤岩配煤及人工智能配煤3种炼焦配煤技术发展历程和现状,凝练了炼焦配煤技术的发展趋势。结合研究实际,重点梳理了煤岩学指标在炼焦配煤中的应用现状。在注重煤岩特征的同时,也需兼顾工艺指标等相关参数对炼焦煤优劣的表征。在实际应用中,各项指标参数的选择和利用需要综合考虑参数适配范围并尊重该指标与炼焦煤特性的真实对应关系。基于以上内容,提出了关联成煤时代、产地等地质因素和黏结指数、胶质层指数等工艺指标的整体思路,实现焦炭性能与原料煤特性的科学、深入关联,构建“本源-过程-结果”一体的优化配煤技术新体系。

SUMO E3 Ligase AtMMS21 Regulates Drought Tolerance in Arabidopsis thaliana

Post-translational modifications of proteins by small ubiquitin-like modifiers （SUMOs） play crucial roles in plant growth and development, and in stress responses. The MMS21 is a newly-identified Arabidopsis thaliana L. SUMO E3 ligase gene aside from the SIZ1, and its function requires further elucidation. Here, we show that MMS21 deficient plants display improved drought tolerance, and constitutive expression of MMS21 reduces drought tolerance. The expression of MMS21 was reduced by abscisic acid （ABA）, polyethylene glycol （PEG） or drought stress. Under drought conditions, mms21 mutants showed the highest survival rate and the slowest water loss, and accumulated a higher level of free proline compared to wild-type （WT） and MMS21 over-expression plants. Stomatal aperture, seed germination and cotyledon greening analysis indicated that mms21 was hypersensitive to ABA. Molecular genetic analysis revealed that MMS21 deficiency led to elevated expression of a series of ABA-mediated stress-responsive genes, including COR15A, RD22, and P5CS1 The ABA and drought-induced stress-responsive genes, including RAB18, RD29A and RD29B, were inhibited by constitutive expression of MMS21. Moreover, ABA-induced accumulation of SUMO-protein conjugates was blocked in the mms21 mutant. We thus conclude that MMS21 plays a role in the drought stress response, likely through regulation of gene expression in an ABA-dependent pathway.

HY5-HDA9 Module Transcriptionally Regulates Plant Autophagy in Response to Light-to-Dark Conversion and Nitrogen Starvation

Light is arguably one of the most important environmental factors that determines virtually all aspects of plant growth and development,but the molecular link between light signaling and the autophagy pathway has not been elucidated in plants.In this study,we demonstrate that autophagy is activated during light-to-dark conversion though transcriptional upregulation of autophagy-related genes(ATGs).We showed that depletion of the ELONGATED HYPOCOTYL 5(HY5),a key component of light signaling,leads to enhanced autophagy activity and resistance to extended darkness and nitrogen starvation treatments,contributing to higher expression oiATGs.HY5 interacts with and recruits HISTONE DEACETYLASE 9(HDA9)to ATG5 and ATG8e loci to repress their expression by deacetylation of the Lys9 and Lys27 of histone 3.Furthermore,we found that both darkness and nitrogen depletion induce the degradation of HY5 via 26S proteasome and the concomitant disassociation of HDA9 from ATG5 and ATG8e loci,leading to their depression and thereby activated autophagy.Genetic analysis further confirmed that HY5 and HDA9 act synergistically and function upstream of the autophagy pathway.Collectively,our study unveils a previously unknown transcriptional and epigenetic network that regulates autophagy in response to light-to-dark conversion and nitrogen starvation in plants.

Lectin receptor kinase OsLecRK-S.7 is required for pollen development and male fertility

Pollen grains are covered by exine that protects the pollen from stress and facilitates pollination.Here we isolated a male sterile mutant s13283 in rice exhibiting aborted pollen with abnormal exine and defective aperture.The mutant gene encodes a novel plasma membrane-localized legume-lectin receptor kinase that we named OsLecRK-S.7.OsLecRK-S.7 was expressed at different levels in all tested tissues and throughout anther development.In vitro kinase assay showed OsLecRK-S.7 capable of autophosporylation.Mutation in s13283(E560K)and mutation of the conserved ATP binding site(K418E)both knocked out the kinase activity.Mass spectrometry showed Thr376,Ser378,Thr386,Thr403,and Thr657 to be the autophosphorylation sites.Mutation of individual autophosphorylation site affected the in vitro kinase activity to different degrees,but did not abolish the gene function in fertility complementation.oslecrk-s.7 mutant plant overexpressing OsLecRK-S.7 recovered male fertility but showed severe growth retardation with reduced number of tillers,and these phenotypes were abolished by E560K or K418E mutation.The results indicated that OsLecRK-S.7 was a key regulator of pollen development.

Perturbation of Auxin Homeostasis Caused by Mitochondrial FtSH4 Gene-Mediated Peroxidase Accumulation Regulates Arabidopsis Architecture

Reactive oxygen species and auxin play important roles in the networks that regulate plant development and morphogenetic changes, However, the molecular mechanisms underlying the interactions between them are poorly understood. This study isolated a mas （More Axillary Shoots） mutant, which was identified as an allele of the mitochondrial AAA-protease AtFtSH4, and characterized the function of the FtSH4 gene in regulating plant development by medi- ating the peroxidase-dependent interplay between hydrogen peroxide （H2Oz） and auxin homeostasis. The phenotypes of dwarfism and increased axillary branches observed in the mas （renamed as ftsh4-4） mutant result from a decrease in the IAA concentration. The expression levels of several auxin signaling genes, including IAA1, IAA2, and IAA3, as well as several auxin binding and transport genes, decreased significantly in ftsh4-4 plants. However, the H202 and peroxidases levels, which also have IAA oxidase activity, were significantly elevated in ftsh4-4 plants. The ftsh4-4 phenotypes could be reversed by expressing the iaaM gene or by knocking down the peroxidase genes PRX34 and PRX33. Both approaches can increase auxin levels in the ftsh4-4 mutant. Taken together, these results provided direct molecular and genetic evidence for the interaction between mitochondrial ATP-dependent protease, H2O2, and auxin homeostasis to regulate plant growth and development.

SUMOylation facilitates the assembly of a Nuclear Factor-Y complex to enhance thermotolerance in Arabidopsis

Heat stress(HS) has serious negative effects on plant development and has become a major threat to agriculture. A rapid transcriptional regulatory cascade has evolved in plants in response to HS. Nuclear Factor-Y(NF-Y) complexes are critical for this mechanism, but how NF-Y complexes are regulated remains unclear.In this study, we identified NF-YC10(NF-Y subunit C10), a central regulator of the HS response in Arabidopsis thaliana, as a substrate of SUMOylation, an important post-translational modification. Biochemical analysis showed that the SUMO ligase SIZ1(SAP AND MIZ1 DOMAINCONTAINING LIGASE1) interacts with NF-YC10and enhances its SUMOylation during HS. The SUMOylation of NF-YC10 facilitates its interaction with and the nuclear translocation of NF-YB3, in which the SUMO interaction motif(SIM)is essential for its efficient association with NF-YC10. Further functional analysis indicated that the SUMOylation of NF-YC10 and the SIM of NF-YB3 are critical for HS-responsive gene expression and plant thermotolerance. These findings uncover a role for the SIZ1-mediated SUMOylation of NF-YC10 in NF-Y complex assembly under HS, providing new insights into the role of a post-translational modification in regulating transcription during abiotic stress responses in plants.

The Pumilio RNA-binding protein APUM24 regulates seed maturation by fine-tuning the BPM-WRI1 module in Arabidopsis

Pumilio RNAbindingproteinsparticipateinmes-senger RNA(mRNA)degradation and t ranslational repression,but their roles in plant development are largely unclear.Here,we show that Arabidopsis PUMILIO PROTEIN24(APUM24),an atypical Pumiliohomology domaincontaining protein,plays an im-portant part in regulating seed maturation,a major stage of plant development.APUM24 is strongly expressed in maturing seeds.Reducing APUM24 expression resulted in abnormal seed maturation,wrinkled seeds,and lower seed oil contents,and APUM24 knockdown resulted in lower levels of WRINKLED 1(WRI1),a key transcription factor con-trolling seed oil accumulation,and lower expression of WRI1 target genes.APUM24 reduces the mRNA stability of BTB/POZMATH(BPM)family genes,thus decreasing BPM protein levels.BPM is responsible for the 26S proteasomemediated degradation of WRI1 and has important functions in plant growth and development.The 3′untranslated regions of BPM family genes contain putative Pumilio response elements(PREs),which are bound by APUM24.Re-duced BPM or increased WRI1 expression rescued the decient seed maturation of apum242 knock-down mutants,and APUM24 overexpression re-sulted in increased seed size and weight.Therefore,APUM24 is crucial to seed maturation through its action as a positive regulatornetuning the BPMWRI1 module,making APUM24 apromising target for breeding strategies to increase crop yields.

A Putative Chloroplast-Localized Ca2＋/H＋ Antiporter CCHA1 Is Involved in Calcium and pH Homeostasis and Required for PSII Function in Arabidopsis

Calcium is important for chloroplast, not only in its photosynthetic but also nonphotosynthetic functions. Mul- tiple Ca2＋/H＋ transporters and channels have been described and studied in the plasma membrane and organ- elle membranes of plant cells; however, the molecular identity and physiological roles of chloroplast Ca2＋/H＋ antiporters have remained unknown. Here we report the identification and characterization of a member of the UPFO016 family, CCHA1 （a chloroplast-localized potential Ca2＋/H＋ antiporter）, in Arabidopsis thaliana. We observed that the ccha I mutant plants developed pale green leaves and showed severely stunted growth along with impaired photosystem II （PSII） function. CCHA1 localizes to the chloroplasts, and the levels of the PSII core subunits and the oxygen-evolving complex were significantly decreased in the ccha I mutants compared with the wild type. In high Ca2＋ concentrations, Arabidopsis CCHA1 partially rescued the growth defect of yeast gdtl3 null mutant, which is defective in a Ca2＋/H＋ antiporter. The cchal mutant plants also showed significant sensitivity to high concentrations of CaCI2 and MnCI2, as well as variation in pH. Taken these results together, we propose that CCHA 1 might encode a putative chloroplast-localized Ca2＋/H＋ antiporter with critical functions in the regulation of PSII and in chloroplast Ca2＋ and pH homeostasis in Arabidopsis.

Chromatin-associated SUMOylation controls the transcriptional switch between plant development and heat stress responses

The post-translational protein modification known as SUMOylation has conserved roles in the heat stress responses of various species.The functional connection between the global regulation of gene expression and chromatin-associatedSUMOylation in plant cells isunknown.Here,weuncovereda genome-wide relationship between chromatin-associated SUMOylation and transcriptional switches in Arabidopsis thaliana grown at room temperature,exposed to heat stress,and exposed to heat stress followed by recovery.The small ubiquitin-like modifier(SUMO)-associated chromatin sites,characterized by whole-genome ChIP-seq,were generally associated with active chromatin markers.In response to heat stress,chromatin-associated SUMO signals increased at promoter-transcriptional start site regions and decreased in gene bodies.RNAseq analysis supported the role of chromatin-associatedSUMOylation in transcriptional activation during rapid responses to high temperature.Changes inSUMOsignals on chromatinwere associated with the upregulation of heat-responsivegenesandthedownregulation ofgrowth-relatedgenes.Disruption of theSUMOligasegene SIZ1 abolished SUMOsignals on chromatin and attenuated rapid transcriptional responses to heat stress.The SUMO signal peaks were enriched in DNA elements recognized by distinct groups of transcription factors under different temperature conditions.These observations provide evidence that chromatin-associated SUMOylation regulates the transcriptional switch between development and heat stress response in plant cells.

HY5-HDA9 Module Transcriptionally Regulates Plant Autophagy in Response to Light-to-Dark Conversion and Nitrogen Starvation

(Molecular Plant 13,515-531;March 2020)After publication of our original manuscript,we became aware of errors in Figure 4.During the preparation of Figure 4C in this article as originally published,we inadvertently duplicated the image of hda9-1(MS-N)as that of the hda9-1-C(MS+N).Also,in Figure 4H,the image of pUBQ10:GFP-ATG8a/hda9-1(MS+L)was mistakenly a duplicate of pUBQ10:GFP-ATG8a/WT(MS+L)shown in Figure S7C.A corrected version of Figure 4 is shown below.The scientific conclusions of this article have not been affected by this correction.The authors apologize for not detecting this error prior to publication and for any inconvenience that may have been caused.

Post-translational modification:a strategic response to high temperature in plants

With the increasing global warming high-temperature stress is affecting plant growth and develop-ment with greater frequency.Therefore,an increasing number of studies examining the mechanism of temperature response contribute to a more optimal understanding of plant growth under environ-mental pressure.Post-translational modification(PTM)provides the rapid reconnection of tr anscrip-tional programs including transcription factors and signaling proteins.It is vital that plants quickly respond to changes in the environment in order to survive under stressful situations.Herein,we discuss several types of PTMs that occur in response to warm-temperature and high-temperature stress,including ubiquitination,SUMOylation,phosphorylation,histone methylation,and acetylation.This review provides a valuable resolution to this issue to enable increased crop productivity at high temperatures.

Lambda-cyhalothrin disrupts the up-regulation effect of 17β-estradiol on post-synaptic density 95 protein expression via estrogen receptor α-dependent Akt pathway

Lambda-cyhalothrin（LCT）,one of the type II pyrethroids,has been widely used throughout the world.The estrogenic effect of LCT to increase cell proliferation has been well established.However,whether the estrogenic effect of LCT will influence neurodevelopment has not been investigated.In addition,17β-Estradiol（E2）plays a crucial role in neurodevelopment and induces an increase in synaptic proteins.The post-synaptic density 95（PSD95）protein,which is involved in the development of the structure and function of new spines and localized with estrogen receptor α（ERα）at the post-synaptic density（PSD）,was detected in our study by using hippocampal neuron cell line HT22.We found that LCT up-regulated PSD95 and ERα expression,estrogen receptor（ER）antagonist ICI182,780 and phosphatidylinositol-4;5-bisphosphate 3-kinase（PI3K）inhibitor LY294,002 blocked this effect.In addition,LCT disrupted the promotion effect of E2 on PSD95.To investigate whether the observed changes are caused by ERα-dependent signaling activation,we next detected the effects of LCT on the ERα-mediated PI3K-Protein kinase B（PKB/Akt）-eukaryotic initiation factor（e IF）4E-binding protein 1（4E-BP1）pathway.There existed an activation of Akt and the downstream factor 4E-BP1 after LCT treatment.In addition,LCT could disrupt the activation effect of E2 on the Akt pathway.However,no changes in c AMP response element-binding protein（CREB）activation and PSD95 messenger ribonucleic acid（m RNA）were observed.Our findings demonstrated that LCT could increase the PSD95 protein level via the ERα-dependent Akt pathway,and LCT might disrupt the up-regulation effect of E2 on PSD95 protein expression via this signaling pathway.

UBC32 Mediated Oxidative Tolerance in Arabidopsis

Extreme environments such as salt stress often increase the reactive oxygen species （ROS） levels （Abogadallah, 2010; Miller et al., 2010）, which cause protein denaturation and damage （Kelsen et al., 2008）. In eukaryotic cells, the endo- plasmic reticulum （ER） lumen is highly oxidative environment, which help newly synthesized proteins form intermolecular or intramolecular disulfide bonds between their cysteine residues. However, the ROS must be regulated according to the folding load to protect the cell from the consequences of oxidative folding.

A robust method for identification of plant SUMOylation substrates in a library-based reconstitution system

Dear Editor,SUMOylation,which transfers a small ubiquitin-like protein to the lysine residues of target proteins,is an important type of posttranslational modification in eukaryotic cells.This modification plays a critical role in plant development and stress responses(Miura and Hasegawa,2010);thus,the efficient identification of SUMOylation substrates in plant cells is a fundamental issue in the field.In Arabidopsis,hundreds of SUMOylated proteins have been identified by a mass spectrometry(MS)approach in which modified targets in transgenic plants harboring an H89R variant of SUMO1 are enriched via affinity chromatography and a four-residue footprint is left on the substrates after trypsin digestion for MS analysis(Miller et al.,2010).Given that antibodies generated against SUMO molecules are not very specific,it is impractical to catch endogenous SUMO moieties via antibody-based one-step purification.Thus,it is difficult to obtain SUMOylation substrates via existing approaches in plant species that cannot be efficiently transformed.Given that SUMOylation is highly reversible(Yates et al.,2016),another problem is that the modification may be removed quickly during sample preparation.In addition,based on the efficiency and sensitivity of affinity enrichment and MS,substrates with low protein levels may be missed in the analyses.