Knockdown of the atypical protein kinase genes GhABC1K2-A05 and GhABC1K12-A07 make cotton more sensitive to salt and PEG stress

Activity of bc1 complex kinase(ABC1K)is an atypical protein kinase(aPK)that plays a crucial role in plant mitochondrial and plastid stress responses,but little is known about the responses of ABC1Ks to stress in cotton(Gossypium spp.).Here,we identified 40 ABC1Ks in upland cotton(Gossypium hirsutum L.)and found that the Gh ABC1Ks were unevenly distributed across 17 chromosomes.The GhABC1K family members included 35 paralogous gene pairs and were expanded by segmental duplication.The GhABC1K promoter sequences contained diverse cis-acting regulatory elements relevant to hormone or stress responses.The qRT-PCR results revealed that most Gh ABC1Ks were upregulated by exposure to different stresses.Gh ABC1K2-A05 and Gh ABC1K12-A07 expression levels were upregulated by at least three stress treatments.These genes were further functionally characterized by virus-induced gene silencing(VIGS).Compared with the controls,the Gh ABC1K2-A05-and Gh ABC1K12-A07-silenced cotton lines exhibited higher malondialdehyde(MDA)contents,lower catalase(CAT),peroxidase(POD)and superoxide dismutase(SOD)activities and reduced chlorophyll and soluble sugar contents under NaCl and PEG stress.In addition,the expression levels of six stress marker genes(Gh DREB2A,Gh SOS1,Gh CIPK6,Gh SOS2,Gh WRKY33,and Gh RD29A)were significantly downregulated after stress in the Gh ABC1K2-A05-and Gh ABC1K12-A07-silenced lines.The results indicate that knockdown of Gh ABC1K2-A05 and Gh ABC1K12-A07 make cotton more sensitive to salt and PEG stress.These findings can provide valuable information for intensive studies of Gh ABC1Ks in the responses and resistance of cotton to abiotic stresses.

Fine mapping and cloning of the sterility gene Bra2Ms in nonheading Chinese cabbage(Brassica rapa ssp.chinensis)

The application of a male-sterile line is an ideal approach for hybrid seed production in non-heading Chinese cabbage(Brassica rapa ssp.chinensis).However,the molecular mechanisms underlying male sterility in B.rapa are still largely unclear.We previously obtained the natural male sterile line WS24-3 of non-heading Chinese cabbage and located the male sterile locus,Bra2Ms,on the A2 chromosome.Cytological observations revealed that the male sterility of WS24-3 resulted from disruption of the meiosis process during pollen formation.Fine mapping of Bra2Ms delimited the locus within a physical distance of about 129 kb on the A2 chromosome of B.rapa.The Bra039753 gene encodes a plant homeodomain(PHD)-finger protein and is considered a potential candidate gene for Bra2Ms.Bra039753 was significantly downregulated in sterile line WS24-3 compared to the fertile line at the meiotic anther stage.Sequence analysis of Bra039753 identified a 369 bp fragment insertion in the first exon in male sterile plants,which led to an amino acid insertion in the Bra039753 protein.In addition,the 369 bp fragment insertion was found to cosegregate with the male sterility trait.This study identified a novel locus related to male sterility in non-heading Chinese cabbage,and the molecular marker obtained in this study will be beneficial for the marker-assisted selection of excellent sterile lines in non-heading Chinese cabbage and other Brassica crops.

In-situ construction of abundant active centers on hierarchically porous carbon electrode toward high-performance phosphate electrosorption: Synergistic effect of electric field and capture sites

Phosphate removal is crucial for eutrophication control and water quality improvement.Electro-assisted adsorption,an eco-friendly elec-trosorption process,exhibited a promising potential for wastewater treatment.However,there are few works focused on phosphate electro-sorption,and reported electrodes cannot attach satisfactory removal capacities and rates.Herein,electro-assisted adsorption of phosphate via in-situ construction of La active centers on hierarchically porous carbon(LaPC)has been originally demonstrated.The resulted LaPC composite not only possessed a hierarchically porous structure with uniformly dispersed La active sites,but also provided good conductivity for interfacial electron transfer.The LaPC electrode achieved an ultrahigh phosphate electrosorption capability of 462.01 mg g^(-1) at 1 V,outperforming most existing electrodes.The superior phosphate removal performance originates from abundant active centers formed by the coupling of electricfield and capture sites.Besides,the stability and selectivity toward phosphate capture were maintained well even under comprehensive conditions.Moreover,a series of kinetics and isotherms models were employed to validate the electrosorption process.This work demonstrates a deep understanding and promotes a new level of phosphate electrosorption.

Cold hardiness estimation of Pinus densiflora var. zhangwuensis based on changes in ionic leakage, chlorophyll fluorescence and other physiological activities under cold stress

Pinus densiflora var. zhangwuensis grows fast, and its drought and salinity resistance are better than Pinus sylvestris var. mongolica. We compared cold hardiness and mechanisms of cold hardiness between the two species, to provide a theoretical basis for promoting and applying P. densiflora var. zhangwuensis in cold regions. A cold stress experiment was carried out on 3-year-old plantlets of P. densiflora var. zhangwuensis and P. sylvestris var. mon- golica after hardening at five temperature regimes, 5, -10, -20, -40, and -60 ℃, respectively. Some indices of needle samples for both species were measured, such as relative conductivity （REL）, maximum photochemical efficiency （Fv/Fm）, malondialdehyde （MDA）, catalase （CAT）, proline （Pro）, soluble sugar （SS）, and stomata density. REL and MDA values of both species after hard- ening had the same trend of increasing, but the trend was opposite in Fv/Fm value with increasing cold stress. Com- pared with P. sylvestris var. mongolica, the P. densiflora var. zhangwuensis had smaller increases in REL and MDA, and a smaller decline in Fv/Fm during cold stress. Com- pared to the control, REL growth of P. densiflora var. zhangwuensis and P. sylvestris var. mongolica at -60 ℃were 0.41 and 0.60, and MDA growth was 29.94 mol g-1 FW and 47.80 mol g-1 FW, and Fv/Fm declines were 0.08 and 0.27. Half-lethal temperatures （LT50） calculated by logistic equation for P. densiflora var. zhangwuensis and P. sylvestris var. mongolica were -58.23 and -50.34 ℃, respectively. These data suggest that cold resistance of P. densiflora var. zhangwuensis is stronger than that of P. sylvestris var. mongolica. Cold-resistance mechanisms of the two species differed. In response to cold stress, P. sylvestris var. mongolica had strong osmotic adjustment ability because of higher Pro and SS content, while P. densiflora var. zhangwuensis had strong antioxidant ability due to stronger CAT activity. Stomata density and diameter of P. densiflora var. zhangwuensis were smaller, as were single leaf area and number of leaves per plant, both characteristics promoting survival in a cold environment. Greater shoot height and total biomass of seedlings of P. densiflora var. zhangwuensis might be another reason for its stronger cold tolerance.

Dissecting the genetic architecture of glucosinolate compounds for quality improvement in flowering stalk tissues of Brassica napus

Glucosinolates(GSLs) and their hydrolytic products contribute to the quality traits of rapeseed flowering stalk tissues, such as taste, flavor and anticarcinogenic properties(Glucoraphanin). However, little is known about the genetic mechanisms of GSL accumulation in rapeseed flowering stalks. In this study, the variation and genetic architecture of GSL metabolites in flowering stalk tissues were investigated for the first time among a panel of 107 accessions. All GSL compounds exhibited continuous and wide variations in the present population. Progoitrin,glucobrassicanapin and gluconapin were the most abundant GSL compounds. Five quantitative trait loci(QTL) significantly associated with three GSL compounds were identified by genome-wide association study. GRA_C04 was under selected during modern breeding, in which the ratio of lower GSL haplotype(HAP2) in the accessions bred before 1990(52.56%) was significantly lower than that after 1990(78.95%). Four candidate genes, BnaA01. SOT16, BnaA06. SOT17, Bna A06. MYB51a, and Bna A06. MYB51b, were identified in the GTL_A01 and 4OH_A06 regions.These findings provide new insights into GSL biosynthesis in flowering stalk tissues and facilitate quality improvement in rapeseed flowering stalks.

A highly effective incubation strategy enhanced the urban bird hatch success

Urbanization is currently considered one of the most rapid types of global environmental change.Urban habitats are biotically and abiotically different from their rural areas,i.e.,the ambient temperature,predator,and food availability.These novel challenges create new selection pressures,which allow one to investigate ecoevolutionary responses to contemporary environmental change.A total of 118 breeding nests were monitored for nest predation in both urban and rural areas from 2018 to 2020.We used environmental factors from urban and rural areas and behavioral data from 439 Chinese Blackbird(Turdus mandarinus)valid incubation days to understand the impact of urbanization on the incubation behavior of blackbirds and its adaptation mechanism to the urban environment.Cities have warmer ambient temperatures and lower predation pressures than rural areas.Urban blackbirds chose the incubation strategy with shorter and more bouts,while rural blackbirds selected the incubation strategy with longer and fewer bouts.The plasticity of incubation behavior of urban blackbirds was higher than that of rural areas,and the range of egg temperature was also higher than that of rural areas.In addition,incubation temperature and the number of bouts per day were the key factors affecting the day survival rate of blackbirds,and the hatching rate of urban blackbirds was higher than that of rural blackbirds.Our results provide evidence for behavioral shifts in blackbirds during adaptation to urbanization and support the central role of behavioral adaptation in the successful colonization of new environments by wildlife.These help us understand the behavioral characteristics required for wildlife to live in cities and the urban adaptors faced environmental pressures.

Hydrothermal synthesis of zeolitic material from circulating fluidized bed combustion fly ash for the highly efficient removal of lead from aqueous solution

The utilization of coal fly ash derived from circulating fluidized bed combustion(CFBFA)still faces great challenges because of its unique characteristics.In this study,a zeolitic material with Na-P1 zeolite as the main phase was successfully synthesized via a hydrothermal method by using CFBFA as the raw material.The effects of hydrothermal temperature,time,and added CTAB amount on the characterizations of synthesized materials were investigated by XRD,SEM,and XPS.The properties of the optimal zeolitic material and its adsorption performance for Pb^(2+)in aqueous solution were evaluated.The influences of pH,initial concentration,dosage,and temperature on Pb^(2+)adsorption were also examined.Results revealed the following optimal parameters for the synthesis of zeolitic material:NaOH concentration of 2 mol·L^(-1),solid-to-liquid ratio of 1:10 g·ml^(-1),hydrothermal temperature of 110℃,hydrothermal time of 9 h,and CTAB amount of 1 g(per 100 ml solution).The adsorption capacities of the zeolitic material reached 329.67,424.69,and 542.22 mg·g^(-1) when the pH values of aqueous solution were 5,6,and 7,respectively.The Pb^(2+)removal efficiency can reach more than 99%in aqueous solution with the initial concentrations of 100-300 mg·L^(-1) under pH 6 and suitable adsorbent dosage.The adsorption and kinetics of Pb^(2+)on the zeolitic material can be described by Langmuir isotherm and pseudo-second-order kinetic models,respectively.The ion exchange between Pb^(2+)and Na^(+)and chemisorption are the main adsorption mechanism.All these findings imply that the synthesis of low-cost adsorbent for Pb^(2+)removal from weak acid and neutral aqueous solution provides a highly effective method to utilize CFBFA.

A Novel Method for the Reconstruction of Road Profiles from Measured Vehicle Responses Based on the Kalman Filter Method

The estimation of the disturbance input acting on a vehicle from its given responses is an inverse problem.To overcome some of the issues related to ill-posed inverse problems,this work proposes a method of reconstructing the road roughness based on the Kalman filter method.A half-car model that considers both the vehicle and equipment is established,and the joint input-state estimation method is used to identify the road profile.The capabilities of this methodology in the presence of noise are numerically demonstrated.Moreover,to reduce the influence of the driving speed on the estimation results,a method of choosing the calculation frequency is proposed.A road vibration test is conducted to benchmark the proposed method.

Mannotriose regulates learning and memory signal transduction in the hippocampus

Rehmannia is a commonly used Chinese herb, which improves ieaming and memory. However, the crucial components of the signal transduction pathway associated with this effect remain elusive. Pri- mary hippocampal neurons were cultured in vitro, insulted with high-concentration （1 × 10-4 mol/L） cor- ticosterone, and treated with 1 × 104 mol/L mannotriose. Thiazolyl blue tetrazolium bromide assay and western blot analysis showed that hippocampal neuron survival rates and protein levels of glucocorti- cold receptor, serum and glucocorticoid-regulated protein kinase, and brain-derived neurotrophic factor were all dramatically decreased after high-concentration corticosterone-induced injury. This effect was reversed by mannotriose, to a similar level as RU38486 and donepezil. Our findings indicate that mannotriose could protect hippocampal neurons from high-concentration corticosterone-induced injury. The mechanism by which this occurred was associated with levels of glucocorticoid receptor protein, serum and glucocorticoid-regulated protein kinase, and brain-derived neurotrophic factor.

Risk Factors for Gastrointestinal Injuries in Acute Coronary Syndrome Patients with Double Antiplatelet Therapy in One-Year Follow-Up

Background: The goal is to determine the incidence of symptomatic gastrointestinal (GI) injuries in acute coronary syndrome (ACS) patients receiving double antiplatelet therapy (DAPT). The risk factors for serious GI complications are also evaluated. Methods: 603 eligible patients from the Department of Cardiology at Zhongda Hospital between January 2014 and August 2015 were enrolled and the occurrence of GI injuries within one year assessed. The risk factors for serious GI complications were identified using cox regression analysis. Results: After one-year follow-up, 108 (17.9%) out of 603 patients developed symptomatic GI injuries: 22 (3.65%) with serious GI complications and 86 (14.2%) with GI symptoms. Drinking habit (95% CI: 1.512 - 8.796;P = 0.004) and previous peptic injury (95% CI: 2.307 - 18.080;P = 0.001) are independent predictors of serious GI complications, while proton pump inhibitor (PPI) was protective (95% CI: 0.120 - 0.699;P = 0.006) per cox regression analysis. Additionally, GI injuries of both serious GI complications and GI symptoms peaked in the first three months. Conclusions: Symptomatic GI injuries were relatively common in ACS patients with DAPT, especially in the first three months. Previous peptic injury and drinking habit were significant independent risk factors for serious GI complications, while PPI played a protective role in ACS with DAPT.

Genomic allele-specific base editing with imperfect gRNA

CRISPR base editor(BE)techniques are a promising tool for precise cytosine(C)to thymine(T),adenine(A)to guanine(G),and C to G base editing(CBE,ABE,and GBE,respectively)without the use of a donor DNA template conversion(Komor et al.,2016;Nishida et al.,2016;Gaudelli et al.,2017;Kurt et al.,2021;Zhao et al.,2021).

Microbial L-malic acid production:History,current progress,and perspectives

L-malic acid(L-MA)is an important intermediate in the tricarboxylic acid cycle and a crucial bulk chemical with various applications in the food,pharmaceutical,and chemical industries.With the rapid advancements in metabolic engineering technology and the global commitment toward fostering a green economy and sustainable development,the large-scale production of L-MA is gradually transitioning from conventional petroleum-based approaches to microbial fermentation.This comprehensive review aims to provide a thorough overview of the historical background and recent advancements in the microbial fermentation production of L-MA,encompassing an in-depth introduction to diverse biosynthetic pathways and host strains.Moreover,this review elucidates the challenges encountered in the industrialization of microbial fermentation production of L-MA,offering a summary of potential solutions and prospects for future research directions.The anticipated outcome of this review is to contribute valuable theoretical guidance toward promoting technological innovation in L-MA production.

Recent advances in the improvement of g-C_(3)N_(4) based photocatalytic materials

g-C_(3)N_(4) have been widely used in the fields of photocatalytic hydrogen production,photocatalytic degradation of dyes and oxidative degradation of toxic gases due to their excellent performance.It has attracted extensive attention in recent years due to its highly efficient photocatalytic capacity of hydrogen generation,water oxidation,carbon dioxide reduction and degradation of organic pollutants.Because of the abundant carbon and nitrogen composition of the earth,large-scale production and industrial applications of this material are possible.The modification of this material makes its performance more excellent so that this new material can obtain a steady stream of vitality.These outstanding works have become important materials and milestones on the road to mankind's photocatalytic hydrogen production.This review will begin with the basic idea of designing,synthesizing and improving g-C_(3)N_(4) based photocatalytic materials,and introduce the latest development of g-C_(3)N_(4) photocatalysts in hydrogen production from four aspects of controlling the carbon/nitrogen ratio,morphology,element doping and heterojunction structure of g-C_(3)N_(4) materials.

Detection navigation baseline in row-following operation of maize weeder based on axis extraction

Detection navigation baseline is primary for the automation of maize weeder in seedling.In the navigation technology based on machine vision,maize seeding or weed near the camera is photographed as a discrete area,while a plant far away from the camera is photographed as a strip area along with other plants in the same row.The two problems cannot be solved by one method.However,in this paper,an algorithm of detection navigation baseline in the row-following operation of maize weeder based on axis extraction was proposed to solve the both problems.Firstly,plants are distinguished from the background based on color feature,and the binary image is acquired.Secondly,plants are described as a set of connected components with numbers after connected components labeling and noise clearing.Thirdly,the axes of all connected components are extracted according to the calculation method of rotary inertia in physics.Next,the abnormal connected components with axes are deleted because the angles between the axes and X-axis are above angle threshold.Then,the judgment model is built based on angle tolerance and distance tolerance,the connected components in a same row based on this model through two-step traversal are merged,and a new axis is re-extracted as the axis of the plant row.Finally,the navigation baselines are detected based on the axes of the plant row.The experimental results show that the accuracy of this algorithm is more than 93%,and the computing time is less than 1.6 s,which can meet the accuracy and real-time performance requirements of maize weeder.

The origin and evolution of the diosgenin biosynthetic pathway in yam

Diosgenin,mainly produced by Dioscorea species,is a traditional precursor of most hormonal drugs in the pharmaceutical industry.The mechanisms that underlie the origin and evolution of diosgenin biosynthesis in plants remain unclear.After sequencing the whole genome of Dioscorea zingiberensis,we revealed the evolutionary trajectory of the diosgenin biosynthetic pathway in Dioscorea and demonstrated the de novo biosynthesis of diosgenin in a yeast cell factory.First,we found that P450 gene duplication and neofunctionalization,driven by positive selection,played important roles in the origin of the diosgenin biosynthetic pathway.Subsequently,we found that the enrichment of diosgenin in the yam lineage was regulated by CpG islands,which evolved to regulate gene expression in the diosgenin pathway and balance the carbon flux between the biosynthesis of diosgenin and starch.Finally,by integrating genes fromplants,animals,and yeast,weheterologously synthesized diosgenin to 10mg/l in genetically-engineered yeast.Our study not only reveals the origin and evolutionary mechanisms of the diosgenin biosynthetic pathway in Dioscorea,but also introduces an alternative approach for the production of diosgenin through synthetic biology.

Increasing targeting scope of adenosine base editors in mouse and rat embryos through fusion of TadA deaminase with Cas9 variants

Dear Editor, The clustered regularly interspaced short palindromic repeat （CRISPR） system has been widely adapted to genome editing to either introduce or correct genetic mutations （Wang et al., 2016）. However, due to competition with the dominant non-homologous end-joining （NHEJ） pathway, precise genome modifications through Cas9-stimulated homologous recombination （HR） is inefficient. Through fusion of cytidine deaminases, APOBEC1 （apolipoprotein B editing complex 1） or AID （activation-induced deaminase）, with Cas9 variants, several groups have developed the cytidine base editor （BE） systems （Komor et al., 2016; Li et al., 2018; Nishida et al., 2016）. The BE system achieves programmable conversion of C-G base pairs to T.A without double-stranded DNA cleavage （Zhou et al., 2017）. More recently, adenine base editors （ABEs）, which efficiently convert A-T base pairs to G-C in genomic DNA, have been developed via fusion of an engineered tRNA adenosine deaminase （ecTadA from Escherichia coh） with nCas9 （Gaudelli et al., 2017）. The ABE system has quickly been adapted to generate disease models and correction of genetic disease in mice （Ryu et al., 2017; Liu et al, 2018）. However, whether the editing efficiency and the targeting scope of ABE could be improved is largely unexplored. In this study, we describe the efficient generation of base-edi- ted mice and rats modeling human diseases through ABEs with highest efficiency up to 100%. We also demonstrate an increase of ABE activity through injection of chemically modified tracrRNA and crRNA in mouse zygotes, and the expansion of editing scope by fusion of an ecTadA mutant to SaCas9n-KKH and Casgn-VQR variants in both cells and embryos. Our study suggests that the ABE system is a powerful and convenient tool to introduce precise base conversions in rodents.

New xylose transporters support the simultaneous consumption of glucose and xylose in Escherichia coli

Glucose and xylose are two major components of lignocellulose.Simultaneous consumption of glucose and xylose is critical for engineered microorganisms to produce fuels and chemicals from lignocellulosic biomass.Although many production limitations have been resolved,glucose‐induced inhibition of xylose transport remains a challenge.In this study,a cell growthbased screening strategy was designed to identify xylose transporters uninhibited by glucose.The glucose pathway was genetically blocked in Escherichia coli so that glucose functions only as an inhibitor and cells need xylose as the carbon source for survival.Through adaptive evolution,omics analysis and reverse metabolic engineering,a new phosphoenolpyruvate:carbohydrate phosphotransferase system(PTS)galactitol transporter(GalABC,encoded by EcolC_1640,EcolC_1641,and EcolC_1642 genes)that is not inhibited by glucose was identified.Inactivation of adenylate cyclase led to increased expression of the EcolC_1642 gene,and a point mutation in gene EcolC_1642(N13S)further enhanced xylose transport.During the second round of gene mining,AraE and a new ABC transporter(AraFGH)of xylose were identified.A point mutation in the transcription regulator araC(L156I)caused increased expression of araE and araFGH genes without arabinose induction,and a point mutation in araE(D223Y)further enhanced xylose transport.These newly identified xylose transporters can support the simultaneous consumption of glucose and xylose and have potential use in producing chemicals from lignocellulose.

作为中介的环节:卢卡奇现实主义小说理论

卢卡奇提出的现实主义小说理论引发了马克思主义文论内部的讨论,布莱希特、阿多诺等人对其理论持批判的态度,在与卢卡奇的论辩中形成了不可通约的僵局。然而,打破这一僵局关系着对卢卡奇现实主义小说理论的再认识,有助于进一步澄清这一不可通约的症结。为此,本文以卢卡奇现实主义小说理论为研究对象,重返卢卡奇的现实主义小说理论生成的马克思主义的理论语境,从审美反映、历史小说、社会存在三个维度,推演出其理论的基石,即主客辩证统一、历史唯物辩证法及“现实的人”的社会存在,在此基础上得出卢卡奇现实主义小说理论与社会历史的具体实践紧密相连,是马克思主义理论体系中至关重要的中介环节。

Correction to: Increasing targeting scope of adenosine base editors in mouse and rat embryos through fusion of TadA deaminase with Cas9 variants

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