The etching strategy of zinc anode to enable high performance zinc-ion batteries

Zinc-ion batteries(ZIBs)are considered to be one of the most promising candidates to replace lithium-ion batteries(LIBs)due to the high theoretical capacity,low cost and intrinsic safety.However,zinc dendrites,hydrogen evolution reaction,surface passivation and other side reactions will inevitably occur during the charging and discharging process of Zn anode,which will seriously affect the cycle stability of the battery and hinder its practical application.The etching strategy of Zn anode has attracted wide attention because of its simple operation and broad commercial prospects,and the etched Zn anode can effectively improve its electrochemical performance.However,there is no comprehensive review of the etching strategy of Zn anode.This review first summarizes the challenges faced by Zn anode,then puts forward the etching mechanisms and properties of acid,salt and other etchants.Finally,based on the above discussion,the challenges and opportunities of Zn anode etching strategy are proposed.

Increased artemisinin production by promoting glandular secretory trichome formation and reconstructing the artemisinin biosynthetic pathway in Artemisia annua

Dear Editor,Artemisinin,which has potent antimalarial properties,is a sesquiterpene endoperoxide originally isolated from the traditional Chinese medicinal plant Artemisia annua.However,the artemisinin content in wild-type(WT)A.annua is low(1-10 mg/g dry weight),leading to its erratic supply and price fluctuations[1].

AaWRKY17, a positive regulator of artemisinin biosynthesis, is involved in resistance to Pseudomonas syringae in Artemisia annua

Artemisia annua,a traditional Chinese medicinal plant,remains the only plant source for artemisinin production,yet few genes have been identified to be involved in both the response to biotic stresses,such as pathogens,and artemisinin biosynthesis.Here,we isolated and identified the WRKY transcription factor(TF)AaWRKY17,which could significantly increase the artemisinin content and resistance to Pseudomonas syringae in A.annua.Yeast one-hybrid(Y1H),dual-luciferase(dual-LUC),and electrophoretic mobility shift assay(EMSA)results showed that AaWRKY17 directly bound to the W-box motifs in the promoter region of the artemisinin biosynthetic pathway gene amorpha-4,11-diene synthase(ADS)and promoted its expression.Real-time quantitative PCR(RT-qPCR)analysis revealed that the transcript levels of two defense marker genes,Pathogenesis-Related 5(PR5)and NDR1/HIN1-LIKE 10(NHL10),were greatly increased in AaWRKY17-overexpressing transgenic A.annua plants.Additionally,overexpression of AaWRKY17 in A.annua resulted in decreased susceptibility to P.syringae.These results indicated that AaWRKY17 acted as a positive regulator in response to P.syringae infection.Together,our findings demonstrated that the novel WRKY transcription factor AaWRKY17 could potentially be used in transgenic breeding to improve the content of artemisinin and pathogen tolerance in A.annua.

Transcriptional regulation of flavonoid biosynthesis in Artemisia annua by AaYABBY5

Artemisia annua is a medicinal plant rich in terpenes and flavonoids with useful biological activities such as antioxidant,anticancer,and antimalarial activities.The transcriptional regulation of flavonoid biosynthesis in A.annua has not been well-studied.In this study,we identified a YABBY family transcription factor,AaYABBY5,as a positive regulator of anthocyanin and total flavonoid contents in A.annua.AaYABBY5 was selected based on its similar expression pattern to the phenylalanine ammonia lyase(PAL),chalcone synthase(CHS),chalcone isomerase(CHI),and flavonol synthase(FLS)genes.A transient dual-luciferase assay in Nicotiana bethamiana with the AaYABBY5 effector showed a significant increase in the activity of the downstream LUC gene,with reporters AaPAL,AaCHS,AaCHI,and AaUFGT.The yeast one-hybrid system further confirmed the direct activation of these promoters by AaYABBY5.Gene expression analysis of stably transformed AaYABBY5 overexpression,AaYABBY5 antisense,and control plants revealed a significant increase in the expression of AaPAL,AaCHS,AaCHI,AaFLS,AaFSII,AaLDOX,and AaUFGT in AaYABBY5 overexpression plants.Moreover,their total flavonoid content and anthocyanin content were also found to increase.AaYABBY5 antisense plants showed a significant decrease in the expression of flavonoid biosynthetic genes,as well as a decrease in anthocyanin and total flavonoid contents.In addition,phenotypic analysis revealed deep purple-pigmented stems,an increase in the leaf lamina size,and higher trichome densities in AaYABBY5 overexpression plants.Together,these data proved that AaYABBY5 is a positive regulator of flavonoid biosynthesis in A.annua.Our study provides candidate transcription factors for the improvement of flavonoid concentrations in A.annua and can be further extended to elucidate its mechanism of regulating trichome development.

The Genome of Artemisia annua Provides Insight into the Evolution of Asteraceae Family and Artemisinin Biosynthesis

Artemisia annua, commonly known as sweet wormwood or Qinghao, is a shrub native to China and has long been used for medicinal purposes. A. annua is now cultivated globally as the only natural source of a potent anti-malarial compound, artemisinin. Here, we report a high-quality draft assembly of the 1.74-gigabase genome of A. annua, which is highly heterozygous, rich in repetitive sequences, and contains 63 226 protein-coding genes, one of the largest numbers among the sequenced plant species. We found that, as one of a few sequenced genomes in the Asteraceae, the A. annua genome contains a large number of genes specific to this large angiosperm clade. Notably, the expansion and functional diversification of genes encoding enzymes involved in terpene biosynthesis are consistent with the evolution of the artemi- sinin biosynthetic pathway. We further revealed by transcriptome profiling that A. annua has evolved the sophisticated transcriptional regulatory networks underlying artemisinin biosynthesis. Based on compre- hensive genomic and transcriptomic analyses we generated transgenic A. annua lines producing high levels of artemisinin, which are now ready for large-scale production and thereby will help meet the chal- lenge of increasing global demand of artemisinin.

Transcriptional regulation of artemisinin biosynthesis in Artemisia annua L.

Artemisinin, also known as qinghaosu, a sesquiterpene endoperoxide lactone isolated from the Chinese medicinal plant Artemisia annua L., is the most effective antimalarial drug which has saved millions of lives.Due to its great antimalarial activity and low content in wild A. annua plants, researches focused on enhancing the artemisin yield in plants became a hotspot. Several families of transcription factors have been reported to participate in regulating the biosynthesis and accumulation of artemisinin.In this review, we summarize recent investigations in these fields, with emphasis on newly identified transcription factors and their functions in artemisinin biosynthesis regulation, and provide new insight for further research.

The AaBBX21–AaHY5 module mediates light-regulated artemisinin biosynthesis in Artemisia annua L.

The sesquiterpene lactone artemisinin is an important anti-malarial component produced by the glandular secretory trichomes of sweet wormwood(Artemisia annua L.).Light was previously shown to promote artemisinin production,but the underlying regulatory mechanism remains elusive.In this study,we demonstrate that ELONGATED HYPOCOTYL5(HY5),a central transcription factor in the light signaling pathway,cannot promote artemisinin biosynthesis on its own,as the binding of AaHY5 to the promoters of artemisinin biosynthetic genes failed to activate their transcription.Transcriptome analysis and yeast two-hybrid screening revealed the B-box transcription factor AaBBX21 as a potential interactor with AaHY5.AaBBX21 showed a trichome-specific expression pattern.Additionally,the AaBBX21–AaHY5 complex cooperatively activated transcription from the promoters of the downstream genes AaGSW1,AaMYB108,and AaORA,encoding positive regulators of artemisinin biosynthesis.Moreover,AaHY5 and AaBBX21 physically interacted with the A.annua E3 ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENIC 1(COP1).In the dark,AaCOP1 decreased the accumulation of AaHY5 and AaBBX21 and repressed the activation of genes downstream of the AaHY5–AaBBX21 complex,explaining the enhanced production of artemisinin upon light exposure.Our study provides insights into the central regulatory mechanism by which light governs terpenoid biosynthesis in the plant kingdom.