鳞木目小孢子叶球山西鳞孢穗（新种）的解剖特征

描述了山西太原西山煤田太原组７号煤层煤核中一种鳞木目的小孢子叶球——山西鳞孢穗（新种）（Ｌｅｐｉｄｏｓｔｒｏｂｕｓｓｈａｎｘｉｅｎｓｅ ｓｐ． ｎｏｖ．）。其主要特征是：孢子叶球较小,长３．５ ｃｍ 以上,直径１．６～１．８ ｃｍ 。轴具管状中柱,孢子叶螺旋状着生于轴上。孢子叶柄长６～７ ｍ ｍ ,远端叶片长１．２ ｃｍ 以上。孢子叶柄具翅,翅长２～２．５ ｍ ｍ 。小孢子囊可能呈袋形,长与孢子叶柄相近,宽约４．５ ｍ ｍ ,高２～３ ｍ ｍ ,以其长度的约２／３着生于孢子叶柄的腹面上。成熟的孢子囊壁仅由一层柱状细胞构成。小孢子直径６８～７７ μｍ ,具三缝,远极面具短刺     

The effect of cerium (III) on the chlorophyll formation in spinach

The effect of Ce³⁺ on the chlorophyll (chl) of spinach was studied in pot culture experiments. The results showed that Ce³⁺ could obviously stimulate the growth of spinach and increase its chlorophyll contents and photosynthetic rate. It could also improve the PSII formation and enhance its electron transport rate of PSII as well. By inductively coupled plasma-mass spectroscopy and atom absorption spectroscopy methods, it was revealed that the rare-earth-element (REE) distribution pattern in the Ce³⁺-treated spinach was leaf>root>shoot in Ce³⁺ contents. The spinach leaves easily absorbed REEs. The Ce³⁺ contents of chloroplast and chlorophyll of the Ce³⁺-treated spinach were higher than that of any other rare earth and were much higher than that of the control; it was also suggested that Ce³⁺ could enter the chloroplast and bind easily to chlorophyll and might replace magnesium to form Ce-chlorophyll. By ultraviolet-visible, Fourier transform infrared, and extended X-ray absorption fine structure (EXAFS) methods, Ce³⁺-coordinated nitrogen of porphyrin rings with eight coordination numbers and average length of the Ce-N bond of 0.251 nm.     

SARS病毒N蛋白的原核重组载体的构建和表达

将SARS病毒N蛋白的基因克隆到原核表达载体 pGEX KG上 ,使其在大肠杆菌DH5α菌株中以与GST蛋白融合的形式表达。采用GluthathionSepharose 4B亲和层析柱对融合蛋白进行纯化 ,并用SDS PAGE和WesternBlot对表达的融合蛋白进行分析鉴定。结果表明 ,本实验成功地构建了高效表达SARS病毒N蛋白的重组表达载体 ,所获得的融合蛋白可以直接用于SARS抗体的检测 ,可用于SARS的早期诊断及SARS疫苗的研究。     

2,4-Diaminopyrimidine MK2 inhibitors. Part II: Structure-based inhibitor optimization

We describe structure-based optimization of a series of novel 2,4-diaminopyrimidine MK2 inhibitors. Co-crystal structures (see accompanying Letter) demonstrated a unique inhibitor binding mode. Resulting inhibitors had IC₅₀ values as low as 19 nM and moderate selectivity against a kinase panel. Compounds 15, 31a, and 31b inhibit TNFα production in peripheral human monocytes.     

区域农业综合生产力的AHP-Fuzzy综合评判

根据系统分析原理,在确定区域农业综合生产力系统的层次结构基础上,用层次分析法确定各因素的权重,用模糊多级综合评判法对各区域综合生产力进行综合的评价．具有一定的科学性和实用价格．     

SNP-based pool genotyping and haplotype analysis accelerate fine-mapping of the wheat genomic region containing stripe rust resistance gene <Emphasis Type="Italic">Yr26</Emphasis>

Key message

NGS-assisted super pooling emerging as powerful tool to accelerate gene mapping and haplotype association analysis within target region uncovering specific linkage SNPs or alleles for marker-assisted gene pyramiding.

Abstract

Conventional gene mapping methods to identify genes associated with important agronomic traits require significant amounts of financial support and time. Here, a single nucleotide polymorphism (SNP)-based mapping approach, RNA-Seq and SNP array assisted super pooling analysis, was used for rapid mining of a candidate genomic region for stripe rust resistance gene Yr26 that has been widely used in wheat breeding programs in China. Large DNA and RNA super-pools were genotyped by Wheat SNP Array and sequenced by Illumina HiSeq, respectively. Hundreds of thousands of SNPs were identified and then filtered by multiple filtering criteria. Among selected SNPs, over 900 were found within an overlapping interval of less than 30 Mb as the Yr26 candidate genomic region in the centromeric region of chromosome arm 1BL. The 235 chromosome-specific SNPs were converted into KASP assays to validate the Yr26 interval in different genetic populations. Using a high-resolution mapping population (>?30,000 gametes), we confined Yr26 to a 0.003-cM interval. The Yr26 target region was anchored to the common wheat IWGSC RefSeq v1.0 and wild emmer WEWSeq v.1.0 sequences, from which 488 and 454 kb fragments were obtained. Several candidate genes were identified in the target genomic region, but there was no typical resistance gene in either genome region. Haplotype analysis identified specific SNPs linked to Yr26 and developed robust and breeder-friendly KASP markers. This integration strategy can be applied to accelerate generating many markers closely linked to target genes/QTL for a trait of interest in wheat and other polyploid species.

     

Characterization of the tunicamycin gene cluster unveiling unique steps involved in its biosynthesis

Tunicamycin, a potent reversible translocase I inhibitor, is produced by several Actinomycetes species. The tunicamycin structure is highly unusual, and contains an 11-carbon dialdose sugar and an α, β-1″,11′-glycosidic linkage. Here we report the identification of a gene cluster essential for tunicamycin biosynthesis by high-throughput heterologous expression (HHE) strategy combined with a bioassay. Introduction of the genes into heterologous non-producing Streptomyces hosts results in production of tunicamycin by these strains, demonstrating the role of the genes for the biosynthesis of tunicamycins. Gene disruption experiments coupled with bioinformatic analysis revealed that the tunicamycin gene cluster is minimally composed of 12 genes (tunA– tunL). Amongst these is a putative radical SAM enzyme (Tun B) with a potentially unique role in biosynthetic carbon-carbon bond formation. Hence, a seven-step novel pathway is proposed for tunicamycin biosynthesis. Moreover, two gene clusters for the potential biosynthesis of tunicamycin-like antibiotics were also identified in Streptomyces clavuligerus ATCC 27064 and Actinosynnema mirums DSM 43827. These data provide clarification of the novel mechanisms for tunicamycin biosynthesis, and for the generation of new-designer tunicamycin analogs with selective/enhanced bioactivity via combinatorial biosynthesis strategies.     

Mass spectrometric U-series dating of Huanglong Cave in Hubei Province,central China: Evidence for early presence of modern humans in eastern Asia

Most researchers believe that anatomically modern humans (AMH) first appeared in Africa 160-190 ka ago, and would not have reached eastern Asia until ∼50 ka ago. However, the credibility of these scenarios might have been compromised by a largely inaccurate and compressed chronological framework previously established for hominin fossils found in China. Recently there has been a growing body of evidence indicating the possible presence of AMH in eastern Asia ca. 100 ka ago or even earlier. Here we report high-precision mass spectrometric U-series dating of intercalated flowstone samples from Huanglong Cave, a recently discovered Late Pleistocene hominin site in northern Hubei Province, central China. Systematic excavations there have led to the in situ discovery of seven hominin teeth and dozens of stone and bone artifacts. The U-series dates on localized thin flowstone formations bracket the hominin specimens between 81 and 101 ka, currently the most narrow time span for all AMH beyond 45 ka in China, if the assignment of the hominin teeth to modern Homo sapiens holds. Alternatively this study provides further evidence for the early presence of an AMH morphology in China, through either independent evolution of local archaic populations or their assimilation with incoming AMH. Along with recent dating results for hominin samples from Homo erectus to AMH, a new extended and continuous timeline for Chinese hominin fossils is taking shape, which warrants a reconstruction of human evolution, especially the origins of modern humans in eastern Asia.     

Effect of Ifchit1 gene of Isaria fumosorosea on mortality,oviposition and oxidase activities of Bemisia tabaci

Isaria fumosorosea is one of important entomopathogenic fungi showed a good potential in controlling Bemisia tabaci. The effects of I. fumosorosea ⊿Ifchit1 mutant (Ifchit1 gene deletion mutant) on the mortality, oviposition, and host immunological response of B. tabaci, on Brassica campestris L. plant, were evaluated under laboratory conditions. The wild-type fungal strain infection significantly increased insect mortality and reduced the oviposition effeciency of B. tabaci, whereas the ⊿Ifchit1 mutant was much less effective, resulting in higher survival and ovipositing of B. tabaci. The activities of four insect enzymes were examined during a time course of fungal infection. Insect phenoloxidase, perioxidase, and catalase activities were decreased in whiteflies treated with the wild type and mutant I. fumosorosea strain at 12–36?h post treatment. However, these enzyme activities increased in fungal-treated whiteflies as compared to controls between 36 and 60?h post-infection, reaching peak values. Superoxide dismutase activity in fungal-treated whiteflies was higher than that in controls during the entire experimental time course examined. The overall enzyme activity profiles in ⊿Ifchit1 mutant-treated whiteflies were significantly different from wild-type strain treatments. Our results showed that loss of the Ifchit1 gene in I. fumosorosea affects whitefly mortality, ovipositioning and various antioxidant enzyme activities, providing new insights into the role of chitinases in I. fumosorosea-insect host–pathogen interactions.     

Lateral Organ Boundaries Domain 19 (LBD19) negative regulate callus formation in Arabidopsis

Plant Cell, Tissue and Organ Culture (PCTOC) - Callus is a remarkable regeneration tissue. The genes correlated with root development can be involved in regulating callus development in higher...