Ideal type 1 is caused by a point mutation in the a-tubulin gene that affects microtubule arrangement in soybean

Plant architecture is a target of crop improvement.The soybean mutant ideal type 1(it1)displays a pleiotropic phenotype characterized by compact plant architecture,reduced plant height,shortened petioles,wrinkled leaves,and indented seeds.Genetic analysis revealed that the pleiotropic phenotype was controlled by an incomplete dominant gene.We characterized the cellular phenotypes of it1 and positionally cloned the it1 locus.Detailed morphogenetic analysis of the it1 mutant revealed an excess of xylem cells and expanded phloem,and polygonal pavement cells.Positional cloning showed that the phenotype was caused by a G-to-A mutation in the second exon of the a-tubulin gene(Glyma.05G157300).The mutation altered microtubule arrangement in pavement cells,changing their morphology.Overexpression of Gmit1 resulted in an it1-like phenotype and polygonal pavement cells and microtubules of overexpressors were parallel or slightly inclined.Five suppressor mutants able to suppress the phenotype of it1 were obtained by EMS mutagenesis in the it1 background.All these mutants carried an additional mutation in the it1 gene.These results suggest that the pleiotropic phenotype of it1 is caused by the mutation in the atubulin gene.

用并行扫描方法开展的表面等离激元电子能谱成像

本文报道了高定向热解石墨上银纳米结构表面等离激元的电子能谱成像研究.本文利用现有扫描探针电子能谱仪的角度色散特性,发展了一种多道测量模式.通过沿一个方向扫描,可以并行获得银纳米结构表面等离激元电子能谱的二维分布.实验确定的能谱成像空间分辨为80 nm左右.

Genome-wide investigation of defensin genes in peanut(Arachis hypogaea L.)reveals AhDef2.2 conferring resistance to bacterial wilt

Peanut(Arachis hypogea L.)bacterial wilt(BW)is a devastating disease caused by Ralstonia solanacearum that results in severe yield and quality losses.Plant defensins are short cysteine-rich peptides with antimicrobial activity.The role of defensin genes(Ah Def)in peanut is unclear.A genome-wide investigation of Ah Def genes was undertaken,and 12 identified Ah Def genes were classified into two groups containing the gamma-thionin domain formed by four disulfide pairs:Cys1-Cys8,Cys2-Cys5,Cys3-Cys6,and Cys4-Cys7.In silico analysis revealed that Ah Def genes showed highly conserved architectural features and contained cis-elements associated with phytohormone signaling and defense responses.A highly resistant cultivar,H108(R)and a susceptible accession,H107(S)were tested by R.solanacearum inoculation.H108(R)showed fewer symptoms than H107(S)owing to inhibition of bacterial reproduction and spread in the vascular bundles of roots and stems.In a transcriptomic expression profile,Ah Def genes,particularly Ah Def1.6 and Ah Def2.2,were up-regulated in H108(R)compared with H107(S)under R.solanacearum infection and phytohormone treatment.Subcellular localization showed that the Ah Def1.6 and Ah Def2.2 proteins were both expressed specifically on the plasma membrane.Overexpression of protein fusion Ah Def2.2-YFP in Nicotiana benthamiana and peanut leaves increased resistance to R.solanacearum,suggesting its role in response to BW infection.Ah Def2.2 may be valuable for peanut resistance breeding.

Evaluation of Chinese medicine on heart failure based on NMR metabolomics

Objective:To evaluate the efficacy of traditional Chinese herbs on heart failure(HF)using nuclear magnetic resonance(NMR)metabolomics.Methods:Plasma metabolomics was conducted on both patients with HF and healthy controls.The partial least squares model was applied to determine potential metabolic markers and related metabolic pathways of the disease.HF patients with the traditional Chinese syndrome pattern of qi deficiency and blood stasis were divided into two groups,and treated,respectively,with conventional medicine and a combination of conventional and Chinese herbs,aimed at tonifying qi and activating blood.Healthy participants served as a control group for comparison.Results and conclusion:Both conventional and herbal treatments appear to regulate disorders of amino acid and glucose metabolism.Combined treatment appears to be more comprehensive,indicating that herbal and conventional medicines exert their effects through different mechanisms in treating HF.It can be further inferred that herbs that tonify qi and activate blood may regulate different essential metabolites.

Mushroom Poisoning Outbreaks—China,2023

What is already known about this topic?Mushroom poisoning poses a significant food safety concern in China,with a total of 196 species identified in poisoning incidents by the end of 2022.What is added by this report?In 2023,the China CDC conducted an investigation into 505 cases of mushroom poisoning spanning 24 provincial-level administrative divisions.This investigation resulted in 1,303 patients and 16 deaths,yielding a case fatality rate of 1.23%.A total of 97 mushrooms were identified as the cause of 6 distinct clinical disease types,with 12 species newly documented as poisonous mushrooms in China.What are the implications for public health practice?Close collaboration among CDC staff,physicians,and mycologists remains crucial for the control and prevention of mushroom poisoning in the future.

Identification and Fine Mapping of rhm1 Locus for Resistance to Southern Corn Leaf Blight in Maize

rhml is a major recessive disease resistance locus for Southern corn leaf blight （SCLB）. To further narrow down its genetic position, F2 population and BCIFI population derived from the cross between resistant （H95rhm） and susceptible parents （H95） of maize （Zea mays） were constructed. Using newly developed markers, rhml was initially delimited within an interval of 2.5 Mb, and then finally mapped to a 8.56 kb interval between InDel marker IDP961-503 and simple sequence repeat （SSR） marker A194149--1. Three polymorphic markers IDP961-504, IDP B2-3 and A194149-2 were shown to be co-segregated with the rhml locus. Sequence analysis of the 8.56 kb DNA fragment revealed that it contained only one putative gene with a predicted amino acid sequence identical to lysine histidine transporter 1 （LHT1）. Comparative sequence analysis indicated that the LHT1 in H95rhrn harbors a 354 bp insertion in its third exon as compared with that of susceptible alleles in B73, H95 and Mo17. The 354 bp insertion resulted in a truncation of the predicted protein of candidate resistance allele （LHT1-H95rhm）. Our results strongly suggest LHTI as the candidate gene for rhml against SCLB. The tightly linked molecular markers developed in this study can be directly used for molecular breeding of resistance to Southern corn leaf blight in maize.

Development and utilization of a new chemically-induced soybean library with a high mutation density

Mutagenized populations have provided important materials for introducing variation and identifying gene function in plants. In this study, an ethyl methanesulfonate（EMS）-induced soybean（Glycine max） population,consisting of 21,600 independent M_2 lines, was developed.Over 1,000 M_（4（5））families, with diverse abnormal phenotypes for seed composition, seed shape, plant morphology and maturity that are stably expressed across different environments and generations were identified. Phenotypic analysis of the population led to the identification of a yellow pigmentation mutant, gyl, that displayed significantly decreased chlorophyll（Chl） content and abnormal chloroplast development. Sequence analysis showed that gyl is allelic to Minn Gold, where a different single nucleotide polymorphism variation in the Mg-chelatase subunit gene（ChlI1a） results in golden yellow leaves. A cleaved amplified polymorphic sequence marker was developed and may be applied to marker-assisted selection for the golden yellow phenotype in soybean breeding. We show that the newly developed soybean EMS mutant population has potential for functional genomics research and genetic improvement in soybean.

金属有机框架:用于功能性表面增强拉曼散射

表面增强拉曼散射(surface-enhanced Raman scattering, SERS)光谱具有高灵敏性、高选择性等优点,能够克服传统拉曼光谱在表面科学和痕量分析中灵敏度低等问题,被应用到生物、食品、环境等领域,为结构表征、物质相互作用和化学反应机理的解释提供了不可或缺的信息.但是SERS基底制备难度大、操作耗时、重复性差等问题制约了表面增强拉曼散射的进一步应用.金属有机框架(metal-organic frameworks, MOF)是一种新型的多孔材料,具有超高孔隙率、极大比表面积、结构多样、易功能化等特性,近年来人们探索将其应用于表面增强拉曼散射中,以实现对特定领域体系中微量乃至痕量成分检测.本文从MOF材料用于SERS不同类型基底的制备出发,讨论了包括MOF单独作为SERS基底、在MOF的外表面固定纳米粒子、在MOF内部嵌入金属粒子、MOF用于核壳结构和MOF用于整合功能单元作为SERS基底等基底制备方法,总结了MOF用于SERS基底的合成策略及增强效果;介绍了当前MOF材料在SERS实际应用领域检测中的研究进展,同时阐明了目前MOF在SERS领域的应用中存在的问题,并对未来此技术的应用领域和发展前景进行展望.