玉米根细胞中对钒酸盐敏感的H~＋－泵的研究

用奎吖咽（ｑｕｉｎａｃｒｉｎｅ）作荧光指标剂,测定玉米（ＺｅａｍａｙｓＬ．）根尖微粒体（ＭＩＣ）膜囊泡的Ｈ~＋－泵活性,结果表明１ｍｍｏｌ／ＬＮａＮ_３仅抑制该泵活性约８％,而０．８ｍｍｏｌ／Ｌ钒酸盐（Ｖａｎ）则可抑制其活性达８０％,说明ＭＩＣ制剂中Ｈ~＋－泵活性主要由质膜（ＰＭ）Ｈ~＋－ＡＴＰａｓｅ产生。此泵活性严格需要Ｍｇ~（２＋）,二价阳离子作用大小的顺序为Ｍｇ~（２＋）＞Ｍｎ~（２＋）＞Ｚｎ~（２＋）＞Ｃａ~（２＋）＝０;阴离子作用大小的１顺序为Ｂｒ~－＞Ｃｌ~－＞ＮＯ_３~－＞ＳＯ_４~（２－）,并初步证实当质膜同侧发生电子传递时,没有跨膜Ｈ~＋梯度（△μＨ~＋）生成。     

非侵入物理疗法——红光照射改善脂多糖诱发小鼠抑郁样行为

目的 抑郁的发生机制不清及药物的临床疗效不佳,导致其成为世界难题。已有研究发现甲醛的气态暴露或液态腹腔注射都可直接诱发小鼠抑郁样行为,而内源甲醛是否参与抑郁的发生尚不清楚。本研究探索脂多糖（lipopolysaccharide,LPS）是否通过刺激内源甲醛产生而诱发小鼠抑郁的分子机制;并观察非侵入物理疗法——630 nm红光照射是否能激活甲醛脱氢酶而降解甲醛,从而改善小鼠抑郁样行为。方法 雄性成年C57BL/6J小鼠随机分组：a.对照组,腹腔注射磷酸缓冲液（phosphate buffer solution,PBS）;b.抑郁模型组,按浓度梯度腹腔注射LPS;c.红光干预组,按浓度梯度腹腔注射LPS后并定时进行630 nm全身红光照射。采用旷场实验（open field test,OFT）、糖水偏爱（suorose preference test,SPT）、悬尾实验（tail suspension test,TST）、强迫游泳（forced swimming test,FST）等方法,评估小鼠的抑郁样行为;用甲醛荧光（Na-FA,特异甲醛荧光探针）定量法及整脑甲醛荧光成像法,检测小鼠脑...     

高粱泡的生长调控与结实状况

高粱泡(Rubus lambertionus Ser.)是一种有利用价值的野生果树资源。其优点为:(1)结果早,产量高,亩产量可达500kg以上;(2)适应性广,耐瘠薄,是开发利用低山丘陵的优良资源植物;(3)果实营养丰富,酸味纯正,尤其是所含红色素稳定性好,是加工果汁饮料的优质添加剂;(4)果实采收期在11月中旬到12月底,此时气温低,有利于浆果加工和贮藏,并可利用农闲季节的劳动力。上述特点表明,高粱泡有很好的开发利用前景。但本种在野生状态下蔓生性强,多刺,并具有枝顶生根的习性,因而树形紊乱而松散,栽培时搭架困难,植株占地面积大,而单位面积产量不易提高。为了便于操作管理和提高产量,减少栽培成本,增进经济效益,我们于1990～1991年进行了生长和株形调控试验,     

Circular RNA AFF4 modulates osteogenic differentiation in BM-MSCs by activating SMAD1/5 pathway through miR-135a-5p/FNDC5/Irisin axis

Bone marrow-derived mesenchymal stem cells (BM-MSCs), the common progenitor cells of adipocytes and osteoblasts, have been recognized as the key mediator during bone formation. Herein, our study aim to investigate molecular mechanisms underlying circular RNA (circRNA) AFF4 (circ_AFF4)-regulated BM-MSCs osteogenesis. BM-MSCs were characterized by FACS, ARS, and ALP staining. Expression patterns of circ_AFF4, miR-135a-5p, FNDC5/Irisin, SMAD1/5, and osteogenesis markers, including ALP, BMP4, RUNX2, Spp1, and Colla1 were detected by qRT-PCR, western blot, or immunofluorescence staining, respectively. Interactions between circ_AFF4 and miR-135a-5p, FNDC5, and miR-135a-5p were analyzed using web tools including TargetScan, miRanda, and miRDB, and further confirmed by luciferase reporter assay and RNA pull-down. Complex formation between Irisin and Integrin αV was verified by Co-immunoprecipitation. To further verify the functional role of circ_AFF4 in vivo during bone formation, we conducted animal experiments harboring circ_AFF4 knockdown, and born samples were evaluated by immunohistochemistry, hematoxylin and eosin, and Masson staining. Circ_AFF4 was upregulated upon osteogenic differentiation induction in BM-MSCs, and miR-135a-5p expression declined as differentiation proceeds. Circ_AFF4 knockdown significantly inhibited osteogenesis potential in BM-MSCs. Circ_AFF4 stimulated FNDC5/Irisin expression through complementary binding to its downstream target molecule miR-135a-5p. Irisin formed an intermolecular complex with Integrin αV and activated the SMAD1/5 pathway during osteogenic differentiation. Our work revealed that circ_AFF4, acting as a sponge of miR-135a-5p, triggers the promotion of FNDC5/Irisin via activating the SMAD1/5 pathway to induce osteogenic differentiation in BM-MSCs. These findings gained a deeper insight into the circRNA-miRNA regulatory system in the bone marrow microenvironment and may improve our understanding of bone formation-related diseases at physiological and pathological levels.Subject terms: Stem cells, Diseases     

Epitranscriptomic technologies and analyses

RNA can interact with RNA-binding proteins(RBPs), mRNA, or other non-coding RNAs(ncRNAs) to form complex regulatory networks. High-throughput CLIP-seq, degradome-seq, and RNA-RNA interactome sequencing methods represent powerful approaches to identify biologically relevant ncRNA-target and protein-ncRNA interactions. However, assigning ncRNAs to their regulatory target genes or interacting RNA-binding proteins(RBPs) remains technically challenging. Chemical modifications to mRNA also play important roles in regulating gene expression. Investigation of the functional roles of these modifications relies highly on the detection methods used. RNA structure is also critical at nearly every step of the RNA life cycle. In this review, we summarize recent advances and limitations in CLIP technologies and discuss the computational challenges of and bioinformatics tools used for decoding the functions and regulatory networks of ncRNAs. We also summarize methods used to detect RNA modifications and to probe RNA structure.     

三氟苯嘧啶不同种子处理方式对稻飞虱的控制效应

为探明三氟苯嘧啶不同种子处理方式对稻飞虱的田间防治效果、防治时长以及对稻田蜘蛛和水稻的安全性,为该药剂种子处理防治稻飞虱提供科学依据,本研究设置10％三氟苯嘧啶悬浮剂按不同浓度(0.375、0.75、1.125和1.5 g a.i./kg种子)对水稻种子分别以干种子拌种(干拌)、清水浸种后拌种(湿拌)和药剂浸种3种方式,清水处理作为空白对照.结果表明,3种处理方式下的水稻发芽率和出苗率均与空白对照间无显著差异,播种后100 d,各浓度对稻飞虱的防治效果均在90％以上;当药剂浓度相同时,干拌与湿拌防治时长要优于药剂浸种;不同浓度三氟苯嘧啶药剂处理在3种方式下稻田蜘蛛种群数量均略低于空白对照田蜘蛛数量.因此,水稻生产中使用三氟苯嘧啶0.375～1.5 g a.i./kg种子干拌或湿拌处理,可有效降低田间稻飞虱种群数量,对天敌蜘蛛影响较小,对水稻种子发芽、出苗安全,可在水稻生产中推广使用.     

甲基营养菌MP688萄糖脱氢酶基因分离鉴定及性质研究

目的：鉴定甲基营养菌MP688中的葡萄糖脱氢酶基因。方法：对甲基营养菌MP688基因组序列进行比对和分析,找到与已知细菌葡萄糖脱氢酶同源性最高的基因序列mpq_2164,且该基因所编码蛋白经分析具有跨膜结构域。设计51物扩增mpq_2164和缺失跨膜区域序列的s-mpq_2164,将PCR产物克隆到表达载雄pET-15b上,在大肠杆菌BL21中完成异源重组表达,然后通过组氨酸标签镍柱亲和层析纯化,采用DCIP法测定葡萄糖脱氢酶的活力。结果：分离了甲基营养菌MP688中的葡糖糖脱氢酶基因,并实现了s-mpq_2164的高效异源重组表达;MPQ2164的氯基酸序列与已知的葡萄糖脱氢酶相似性很低,但酶活测定结果表明S-MPQ-2164具有很高的葡糖糖脱氢酶活性。结论：MPQ_2164是-个依赖于吡咯喹啉醌的葡萄糖脱氢酶,去掉跨膜结构域有利于该蛋白的异源嘉{大,     

人p53启动子萤光素酶报告基因的构建及其活性测定

目的：克隆p53基因的启动子,插入萤光素酶报告基因载体,并检测启动子活性。方法：采用PCR技术从人肝癌细胞系HepG2基因组中扩增人p53启动子,插入萤光素酶报告基因载体pGL4．0-empty,将重组质粒转染293T、ZR75-1、HepG2、A549细胞,测定p53启动子的转录活性。结果：构建了p53启动子的萤光素酶报告基因;通过测序及质粒酶切鉴定,所构建的p53启动子正确;活性实验表明,报告基因在多种细胞中显示构建的p53启动子活性,并呈现一定的剂量效应;转录因子USF能以剂量效应方式提高p53报告基因的转录活性。结论：克隆了人p53启动子,为进一步研究调控p53的转录因子奠定了基础。     

C2ORF40 suppresses breast cancer cell proliferation and invasion through modulating expression of M phase cell cycle genes

Recently, it has been suggested that C2ORF40 is a candidate tumor suppressor gene in breast cancer. However, the mechanism for reduced expression of C2ORF40 and its functional role in breast cancers remain unclear. Here we show that C2ORF40 is frequently silenced in human primary breast cancers and cell lines through promoter hypermethylation. C2ORF40 mRNA level is significantly associated with patient disease-free survival and distant cancer metastasis. Overexpression of C2ORF40 inhibits breast cancer cell proliferation, migration and invasion. By contrast, silencing C2ORF40 expression promotes these biological phenotypes. Bioinformatics and FACS analysis reveal C2ORF40 functions at G2/M phase by downregulation of mitotic genes expression, including UBE2C. Our results suggest that C2ORF40 acts as a tumor suppressor gene in breast cancer pathogenesis and progression and is a candidate prognostic marker for this disease.     

Classifying human operator functional state based on electrophysiological and performance measures and fuzzy clustering method

The human operator’s ability to perform their tasks can fluctuate over time. Because the cognitive demands of the task can also vary it is possible that the capabilities of the operator are not sufficient to satisfy the job demands. This can lead to serious errors when the operator is overwhelmed by the task demands. Psychophysiological measures, such as heart rate and brain activity, can be used to monitor operator cognitive workload. In this paper, the most influential psychophysiological measures are extracted to characterize Operator Functional State (OFS) in automated tasks under a complex form of human–automation interaction. The fuzzy c-mean (FCM) algorithm is used and tested for its OFS classification performance. The results obtained have shown the feasibility and effectiveness of the FCM algorithm as well as the utility of the selected input features for OFS classification. Besides being able to cope with nonlinearity and fuzzy uncertainty in the psychophysiological data it can provide information about the relative importance of the input features as well as the confidence estimate of the classification results. The OFS pattern classification method developed can be incorporated into an adaptive aiding system in order to enhance the overall performance of a large class of safety–critical human–machine cooperative systems.