TaER Expression Is Associated with Transpiration Efficiency Traits and Yield in Bread Wheat

ERECTA encodes a receptor-like kinase and is proposed as a candidate for determining transpiration efficiency of plants. Two genes homologous to ERECTA in Arabidopsis were identified on chromosomes 6 (TaER2) and 7 (TaER1) of bread wheat (Triticum aestivum L.), with copies of each gene on the A, B and D genomes of wheat. Similar expression patterns were observed for TaER1 and TaER2 with relatively higher expression of TaER1 in flag leaves of wheat at heading (Z55) and grain-filling (Z73) stages. Significant variations were found in the expression levels of both TaER1 and TaER2 in the flag leaves at both growth stages among 48 diverse bread wheat varieties. Based on the expression of TaER1 and TaER2, the 48 wheat varieties could be classified into three groups having high (5 varieties), medium (27 varieties) and low (16 varieties) levels of TaER expression. Significant differences were also observed between the three groups varying for TaER expression for several transpiration efficiency (TE)- related traits, including stomatal density (SD), transpiration rate, photosynthetic rate (A), instant water use efficiency (WUEi) and carbon isotope discrimination (CID), and yield traits of biomass production plant^-1 (BYPP) and grain yield plant^-1 (GYPP). Correlation analysis revealed that the expression of TaER1 and TaER2 at the two growth stages was significantly and negatively associated with SD (P<0.01), transpiration rate (P<0.05) and CID (P<0.01), while significantly and positively correlated with flag leaf area (FLA, P<0.01), A (P<0.05), WUEi (P<0.05), BYPP (P<0.01) and GYPP (P<0.01), with stronger correlations for TaER1 than TaER2 and at grain-filling stage than at heading stage. These combined results suggested that TaER involved in development of transpiration efficiency -related traits and yield in bread wheat, implying a function for TaER in regulating leaf development of bread wheat and contributing to expression of these traits. Moreover, the results indicate that TaER could be exploitable for manipulating important agronomical traits in wheat improvement.     

平欧杂种榛叶片解剖结构的抗旱性研究

为研究平欧杂种榛在新疆干旱地区的生态适应性,以新疆伊犁察布查尔县种质资源汇集圃内的38个品种(系)平欧杂种榛为试验材料,采用石蜡制片法,应用光学显微技术测定了叶片上表皮厚度、下表皮厚度、叶片厚度、主脉厚度、栅栏组织厚度、海绵组织厚度、栅栏组织厚度/海绵组织厚度(栅海比)、栅栏组织结构紧密度和海绵组织结构疏松度等9个抗旱相关的解剖结构特征参数,并进行统计分析和抗旱性综合评价。结果表明:(1)不同品种(系)主脉厚度、上下表皮厚度、叶片厚度、栅栏组织厚度和海绵组织厚度均表现出极显著水平差异,叶片上表皮厚度、下表皮厚度、叶片厚度、栅栏组织厚度和海绵组织厚度之间呈极显著相关和显著相关关系。(2)主成分分析表明,第1、2、3主成分的特征值分别为3.109、2.614和1.884,前3个主成分的累计贡献率达84.52%,基本能概括所有指标的主要信息。(3)采用聚类分析法将38个材料分成5大类;隶属函数法综合评价抗旱能力显示,材料84-48、81-21、84-310、F-03、B-11、85-162的抗旱性较强,材料85-127、85-88、B-21、80-4的抗旱性较差。     

A barley stripe mosaic virus-based guide RNA delivery system for targeted mutagenesis in wheat and maize

Plant RNA virus-based guide RNA (gRNA) delivery has substantial advantages compared to that of the conventional constitutive promoter-driven expression due to the rapid and robust amplification of gRNAs during virus replication and movement. To date, virus-induced genome editing tools have not been developed for wheat and maize. In this study, we engineered a barley stripe mosaic virus (BSMV)-based gRNA delivery system for clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9-mediated targeted mutagenesis in wheat and maize. BSMV-based delivery of single gRNAs for targeted mutagenesis was first validated in Nicotiana benthamiana. To extend this work, we transformed wheat and maize with the Cas9 nuclease gene and selected the wheat TaGASR7 and maize ZmTMS5 genes as targets to assess the feasibility and efficiency of BSMV-mediated mutagenesis. Positive targeted mutagenesis of the TaGASR7 and ZmTMS5 genes was achieved for wheat and maize with efficiencies of up to 78% and 48%. Our results provide a useful tool for fast and efficient delivery of gRNAs into economically important crops.     

结核分枝杆菌硫醇乙酰基转移酶基因敲除株的构建及其生物学特性分析

为探索硫醇乙酰基转移酶(mycothiol acetyltransferase,MshD)在结核分枝杆菌中的生物学特性,本实验利用噬菌体为载体的同源重组技术,构建结核分枝杆菌mshD基因敲除株、mshD基因回补株,用实时定量聚合酶链反应(real time-quantitative polymerase chain reaction, RT-qPCR)对所构建的菌株进行验证。分别收集H37Ra野生株、mshD基因敲除株、mshD基因回补株对数生长期菌液各5 mL, 离心收集菌体并培养,以观察菌落形态、生物膜形成及生长曲线测定;用5 mmol/L H₂O₂、0.05% SDS,50 ℃热激及低氧条件下分别处理基因敲出菌株和野生菌株,将菌液进行10倍梯度稀释,培养4～6周后检测抗胁迫能力并计算存活率。结果显示, 与野生株H37Ra相比,mshD基因敲除株菌落褶皱减少且菌落偏小,生长趋势较为缓慢;生物膜形成所需时间增长且褶皱明显减少;抗逆能力下降,存活率略低于野生株和回补株。揭示了mshD基因对结核分枝杆菌的生长具有重要作用,为进一步揭示该基因的功能和作用机制奠定了基础。     

Application of next-generation sequencing to screen for pathogenic mutations in 123 unrelated Chinese patients with Marfan syndrome or a related disease

Marfan syndrome(MFS) is a systemic connective tissue disease principally affecting the ocular, skeletal and cardiovascular systems. This autosomal dominant disorder carries a prevalence of 1:3,000 to 1:5,000. This study aims to define the mutational spectrum of MFS related genes in Chinese patients and to establish genotype-phenotype correlations in MFS. Panel-based targeted next-generation sequencing was used to analyze the FBN1, TGFBR1 and TGFBR2 genes in 123 unrelated Chinese individuals with MFS or a related disease. Genotype-phenotype correlation analyses were performed in mutation-positive patients. The results showed that 97 cases/families(78.9%; 97/123) harbor at least one(likely) pathogenic mutation, most of which were in FBN1; four patients had TGFBR1/2 mutations; and one patient harbored a SMAD3 mutation. Three patients had two FBN1 mutations, and all patients showed classical MFS phenotypes. Patients with a dominant negative-FBN1 mutation had a higher prevalence of ectopia lentis(EL). Patients carrying a haploinsufficiency-FBN1 mutation tended to have aortic dissection without EL. This study extends the spectrum of genetic backgrounds of MFS and enriches our knowledge of genotype-phenotype correlations.     

河流着生藻类多样性对城镇化的响应——以深圳市为例

着生藻类是河流生态状况的重要指示生物,然而关于城镇化对着生藻类多样性影响的研究还较缺乏。本研究基于深圳市9条主要河流74个样点2020年雨、旱季的调查数据,对比了城区、郊区河流样点的着生藻类α、β多样性。两次调查共鉴定出着生藻类301个分类单元,其中硅藻门种类最多。谷皮菱形藻（Nitzschia palea）、隐头舟形藻（Navicula cryptocephala）、平庸菱形藻（Nitzschia inconspicua）等污染指示种在城区组相对丰度更高,而清洁指示种微小曲丝藻（Achnanthidium minutissimum）在郊区组相对丰度更高。城镇化对着生藻类物种丰富度、香农维纳多样性指数、Pielou均匀度指数等α多样性指数均无显著影响,但对着生藻类群落结构有显著影响。城区组样点的着生藻类β多样性（用主坐标分析质心指示）低于郊区组,城区组与郊区组藻类β多样性差异在旱季更为显著。两组样点的藻类β多样性差异主要来源于物种周转组分。与城区组着生藻类群落显著相关的环境因子包括总氮、高锰酸钾指数、电导率、pH、浊度和水深,而与郊区组着生藻类群落显著相关的是总氮、溶解性无机磷和电导率。研究发现,城市人类活动导致的总氮、溶解性无机磷、高锰酸钾指数、电导率等指标的显著增高导致着生藻类β多样性的降低。为了保护河流生物多样性,建议有效控制城区生产生活污水排放,减少人类活动对河流的干扰。     

OsRLCK160 contributes to flavonoid accumulation and UV-B tolerance by regulating OsbZIP48 in rice

Science China Life Sciences - Plants produce specialized metabolites to adapt to the ever-changing environments. Flavonoids are antioxidants essential for growth, development, and breeding with...     

Indirubin-3-Oxime Prevents H<Subscript>2</Subscript>O<Subscript>2</Subscript>-Induced Neuronal Apoptosis via Concurrently Inhibiting GSK3β and the ERK Pathway

Oxidative stress-induced neuronal apoptosis plays an important role in many neurodegenerative disorders. In this study, we have shown that indirubin-3-oxime, a derivative of indirubin originally designed for leukemia therapy, could prevent hydrogen peroxide (H₂O₂)-induced apoptosis in both SH-SY5Y cells and primary cerebellar granule neurons. H₂O₂ exposure led to the increased activities of glycogen synthase kinase 3β (GSK3β) and extracellular signal-regulated kinase (ERK) in SH-SY5Y cells. Indirubin-3-oxime treatment significantly reversed the altered activity of both the PI3-K/Akt/GSK3β cascade and the ERK pathway induced by H₂O₂. In addition, both GSK3β and mitogen-activated protein kinase inhibitors significantly prevented H₂O₂-induced neuronal apoptosis. Moreover, specific inhibitors of the phosphoinositide 3-kinase (PI3-K) abolished the neuroprotective effects of indirubin-3-oxime against H₂O₂-induced neuronal apoptosis. These results strongly suggest that indirubin-3-oxime prevents H₂O₂-induced apoptosis via concurrent inhibiting GSK3β and the ERK pathway in SH-SY5Y cells, providing support for the use of indirubin-3-oxime to treat neurodegenerative disorders caused or exacerbated by oxidative stress.     

岩溶石漠化区不同植被恢复模式土壤无机磷形态特征及影响因素

为分析岩溶石漠化区不同植被恢复模式土壤无机磷的形态特征,评价植被恢复的土壤供磷潜力,阐明有机碳及钙素在无机磷形态转化中的作用,选取研究区内8种有代表性的样地,采用蒋柏藩无机磷分级方法对土壤无机磷形态特征及影响因素进行研究。结果表明:研究区土壤全磷与速效磷含量分别在0.25—1.35 g/kg、1.05—53.01 mg/kg范围,无机磷总量在123.94—934.61 mg/kg,耕地与退耕地以及各退耕地之间全磷、速效磷、各形态无机磷含量水平差异明显,各退耕地磷素含量水平介于耕地与次生马尾松林地之间,退耕地中桃林地、花椒林地磷素含量水平较高、樟树林地、柳杉林地、撂荒草地次之、撂荒灌丛地较低。各样地土壤无机磷占全磷比例在51.2%—72.4%,不同形态的无机磷含量表现为O-PFe-PCa-PAl-P,其中Ca2-P、Al-P对速效磷的贡献率大,Fe-P、Ca8-P贡献较小,O-P、Ca10-P献率最小。不同活性土壤有机碳与不同形态钙素对各形态无机磷在总无机磷中比例的影响较大,p H、容重、粘粒含量、含水量等其它理化性质影响较小。     

Multilocus typing of Cryptosporidium spp. and Giardia duodenalis from non-human primates in China

Non-human primates (NHPs) are commonly infected with Cryptosporidium spp. and Giardia duodenalis. However, molecular characterisation of these pathogens from NHPs remains scarce. In this study, 2,660 specimens from 26 NHP species in China were examined and characterised by PCR amplification of 18S rRNA, 70 kDa heat shock protein (hsp70) and 60 kDa glycoprotein (gp60) gene loci for Cryptosporidium; and 1,386 of the specimens by ssrRNA, triosephosphate isomerase (tpi) and glutamate dehydrogenase (gdh) gene loci for Giardia. Cryptosporidium was detected in 0.7% (19/2660) specimens of four NHP species including rhesus macaques (0.7%), cynomolgus monkeys (1.0%), slow lorises (10.0%) and Francois’ leaf monkeys (6.7%), belonging to Cryptosporidium hominis (14/19) and Cryptosporidium muris (5/19). Two C. hominis gp60 subtypes, IbA12G3 and IiA17 were observed. Based on the tpi locus, G. duodenalis was identified in 2.2% (30/1,386) of specimens including 2.1% in rhesus macaques, 33.3% in Japanese macaques, 16.7% in Assam macaques, 0.7% in white-headed langurs, 1.6% in cynomolgus monkeys and 16.7% in olive baboons. Sequence analysis of the three targets indicated that all of the Giardia-positive specimens belonged to the zoonotic assemblage B. Highest sequence polymorphism was observed at the tpi locus, including 11 subtypes: three known and eight new ones. Phylogenetic analysis of the subtypes showed that most of them were close to the so-called subtype BIV. Intragenotypic variations at the gdh locus revealed six types of sequences (three known and three new), all of which belonged to so-called subtype BIV. Three specimens had co-infection with C. hominis (IbA12G3) and G. duodenalis (BIV). The presence of zoonotic genotypes and subtypes of Cryptosporidium spp. and G. duodenalis in NHPs suggests that these animals can potentially contribute to the transmission of human cryptosporidiosis and giardiasis.