Cotton S-adenosylmethionine decarboxylase-mediated spermine biosynthesis is required for salicylic acid- and leucine-correlated signaling in the defense response to Verticillium dahliae

Planta - Cotton S-adenosylmethionine decarboxylase-, rather than spermine synthase-, mediated spermine biosynthesis is required for salicylic acid- and leucine-correlated signaling in the defense...     

Comprehensive profiling of accessible surface glycans of mammalian sperm using a lectin microarray

It is well known that cell surface glycans or glycocalyx play important roles in sperm motility, maturation and fertilization. A comprehensive profile of the sperm surface glycans will greatly facilitate both basic research (sperm glycobiology) and clinical studies, such as diagnostics of infertility. As a group of natural glycan binders, lectin is an ideal tool for cell surface glycan profiling. However, because of the lack of effective technology, only a few lectins have been tested for lectin-sperm binding profiles. To address this challenge, we have developed a procedure for high-throughput probing of mammalian sperm with 91 lectins on lectin microarrays. Normal sperm from human, boar, bull, goat and rabbit were collected and analyzed on the lectin microarrays. Positive bindings of a set of ~50 lectins were observed for all the sperm of 5 species, which indicated a wide range of glycans are on the surface of mammalian sperm. Species specific lectin bindings were also observed. Clustering analysis revealed that the distances of the five species according to the lectin binding profiles are consistent with that of the genome sequence based phylogenetic tree except for rabbit. The procedure that we established in this study could be generally applicable for sperm from other species or defect sperm from the same species. We believe the lectin binding profiles of the mammalian sperm that we established in this study are valuable for both basic research and clinical studies.     

宁夏枸杞内生细菌的多样性及其抑菌活性研究

【目的】对宁夏枸杞各药用部位内生细菌的分布特征、遗传多样性和抑菌活性进行分析。【方法】采用菌落计数和16S rRNA基因序列分析法研究枸杞内生细菌的分布特征、遗传多样性,采用琼脂扩散法测定其抑菌活性。【结果】从各药用组织器官中分离出内生细菌34株,隶属于7科11属,内生细菌的数量和群落组成存在明显的组织特异性,其数量表现为根皮>叶>花>果实,而多样性则表现为花>根皮>叶>果实。芽孢杆菌属为枸杞优势内生菌群,分布于所有组织中;抑菌实验结果表明有76.5%的内生菌对一种或多种病原菌的生长有抑制作用,芽孢杆菌属菌株R2、R7、L3和短波单胞菌属的R3拮抗番茄炭疽杆菌和玉米大斑病菌的能力较强,而多数菌株对大肠杆菌和金黄色葡萄球菌的抑制能力较弱。【结论】枸杞可培养内生细菌遗传多样性丰富,对植物病原菌有较强的抑制活性。     

Ace2, rather than ace1, is the major acetylcholinesterase in the silkworm, Bombyx mori

Abstract  Two acetylcholinesterase ( ace ) genes have been reported in many insect species. In pests such as Helicoverpa assulta and Plutella xylostellas , ace 1 gene encodes the predominant synaptic enzyme that is the main target of organophosphorus (OP) and carbamate pesticides. It has been reported that pesticide selection has an impact on the ace gene evolution. The domesticated silkworm, Bombyx mori , also has two ace genes. We studied ace gene expression and enzyme activities in silkworm as this has not faced pesticide selection over the past decades. The expression levels of two ace genes, Bm- ace 1 and Bm- ace 2, were estimated by quantitative real-time polymerase chain reaction. Bm- ace 2 was expressed more highly than Bm- ace 1 in all tested samples of different developmental stages or tissues, suggesting ace 2, rather than ace 1, is the major type of acetylcholinesterase (AChE) in Bombyx mori . This is inconsistent with the aforementioned lepidopterons agricultural pests, partly be due to the widespread use of pesticides that may induce high expression of the ace 1 gene in these pests. Besides high expression in the head, Bm- ace 1 also expresses highly in the silk glands and Bm- ace 2 is abundant in the germline, implying both ace genes may have potential non-hydrolytic roles in development. Furthermore, we found that the mRNA levels of two ace genes and their ratios ( ace 2/ ace 1) change day to day in the first and third instars. This challenges the conventional method of estimating enzymatic activity using crude extract as an enzyme solution, as it is a mixture of AChE1 and AChE2. An efficient and simple method for separating different AChEs is necessary for reliable toxicological analyses.     

湖北省荆门荆山余脉种子植物区系研究

对湖北省荆门荆山余脉种子植物区系进行了统计分析。结果表明:(1)物种多样性丰富,共有野生种子植物128科、576属、1226种;(2)优势科、属明显;(3)分布区类型多样,地理成分复杂;(4)温带性质明显,热带成分丰富,与热带植物区系有较高的亲缘关系,并表现出一定的过渡性;(5)区划上属于华东植物地区。     

piRNA-Triggered MIWI Ubiquitination and Removal by APC/C in Late Spermatogenesis

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Highlights? MIWI is a substrate of APC/C, and piRNA loading is essential for MIWI ubiquitination ? piRNA loading promotes MIWI binding to the APC/C substrate-binding subunit ? MIWI and piRNAs are coordinately eliminated in late spermatids ? Inhibition of MIWI destruction in late spermatids prevents sperm maturation     

产氢菌Enterobacter sp.和Clostridium sp.的分离鉴定及产氢特性

在高温水体中分离得到2株具有较高产氢活性的微生物菌株Z-16和C-32。根据两菌株的16SrDNA序列分析,初步鉴定菌株Z-16为Enterobactersp.,菌株C-32为Clostridiumsp.。研究了起始pH值、反应温度、碳源等对菌株放氢活性的影响。菌株Z-16的最适产氢条件为:反应系统起始pH7·0,反应温度35℃,以蔗糖为产氢底物。在最适条件下,菌株Z-16的氢转化率为2·68molH2/mol蔗糖。菌株C-32的最适产氢条件为:反应系统起始pH8·0,反应温度35℃,以麦芽糖为产氢底物。在最适条件下,菌株C-32的氢转化率为2·71molH2/mol麦芽糖。以葡萄糖为碳源时,菌株Z-16和菌株C-32的氢转化率分别为2·35和2·48molH2/mol葡萄糖。     

Improving freezing tolerance of transgenic tobacco expressing sucrose: sucrose 1-fructosyltransferase gene from Lactuca sativa

Sucrose: sucrose 1-fructosyltransferase (1-SST) cDNA from Lactuca sativa, coding the enzyme responsible for lower degree polymers fructan biosynthesis, was cloned by RT-PCR and RACE methods. The 1-SST cDNA under the control of CaMV 35S promoter was introduced into tobacco by Agrobacterium-mediated leaf disc transformation protocol. Fructan synthesis in vitro and carbohydrate analysis showed that sense transgenic tobacco plant displayed sucrose: sucrose 1-fructosyltransferse activity. After freezing stress, significant increases in electrolyte leakage and malondialdehyde were found in the wild type and anti-sense transgenic plants, while no apparent differences were observed in sense transgenic plants. Meanwhile, water soluble carbohydrate, fructan and fructose of sense transgenic plants remarkably increased, compared with those of wild type and anti-sense plants. No significant difference was detected in superoxide dismutase activity between transgenic and wild type plants. The above results demonstrated that the expression of 1-SST gene improved the freezing resistance of transgenic tobacco plants.     

家蚕对浓核病毒中国株(BmDNV-3)抗性及感性品系中肠的差异蛋白质分析

【目的】通过比较家蚕Bombyx mori抗性及感性品系的中肠蛋白质表达谱,获得家蚕对家蚕浓核病毒中国株（BmDNV-3）抗性相关的蛋白。【方法】利用双向电泳(2-DE)对感性品种华八35和抗性品种秋丰接种病毒后48 h的蛋白质表达谱进行比较分析,并对其中的差异蛋白进行MALDI-TOF-TOF质谱分析,通过NCBInr和MSDB数据库进行蛋白点的鉴定和功能分析。【结果】获得重复性较好的差异蛋白点16个,其中质谱鉴定出5种蛋白,它们分别是糖基转移酶（glycosyltransferase）、糖基转移酶-S（GlcAT-S）、21.5 kD小热休克蛋白（21.5 kD small heat shock protein）、V-ATP酶（vacuolar ATP synthase）和精氨酸激酶（arginine kinase）。这5种蛋白在抗性品系秋丰中的表达量均高于感性品系华八35。【结论】糖基转移酶和糖基转移酶-S仅在抗性品系中存在,提示它们可能是与抗性有关的蛋白。此外,增强的应激反应和能量代谢也可能与家蚕对BmDNV-3的抗性产生相关。