中华蜜蜂气味结合蛋白AcerOBP14的表达及配体结合特性分析

[目的]气味结合蛋白(odorant binding proteins,OBPs)在昆虫寄主定位、产卵地选择等行为中发挥着重要作用,明确中华蜜蜂Apis cerana cerana AcerOBP14与配体的结合特性有助于阐明中华蜜蜂嗅觉识别的分子机制.[方法]通过qRT-PCR测定OBP14在20日龄中华蜜蜂成年工蜂...     

新疆典型蝗虫适生区分布预测

新疆草原面积广阔,农牧业地位突出,蝗灾对当地经济、生态威胁很大,近年新疆极端天气日渐频发,蝗灾监测与防治任务艰巨。以意大利蝗、西伯利亚蝗和亚洲飞蝗为代表的蝗虫数据为基础,综合考虑对蝗虫各生命周期有重要影响的环境因素,运用BIOCLIM模型、领域模型(DOMAIN)、马氏距离模型(MAHAL)、广义线性模型(GLM)、随机森林模型(RF)、提升回归树模型(BRT)、支持向量机模型(SVM)、最大熵模型(MaxEnt)等八种经典物种分布模型及集成模型对新疆典型蝗虫适生区展开了预测。结果表明：(1)不同模型对新疆典型蝗虫适生区预测存在差异,其中DOMAIN最差(曲线下面积(AUC)=0.688,真实技巧统计(TSS)=0.301),而提升回归树(BRT)最佳(AUC=0.920,TSS=0.910),基于BRT、SVM和MaxEnt 3个集成模型预测的新疆蝗虫适生区可靠性更高;(2)新疆典型蝗虫不同等级适生区面积约56.844万km²,占新疆总面积的36%,其中高适生区面积16.568万km²;(3)新疆典型蝗虫适生区主要集中于北疆阿勒泰、塔城地区...     

广西西部石灰岩地区生物多样性保护意义与持续利用设想

广西西部石灰岩地区包括北热带、南亚热带和中亚热带的广阔范围,生物多样性和文化多样性的丰富性和独特性不仅在中国,而且在世界上都称得上是一个独一无二的区域。但是,长期以来,对它的研究并不充分,资源管护能力亟待提高,仍处于一种比较贫困的状态。为此,集中相应的人力物力,加大保护的力度并和区域经济的可持续发展密切结合起来是一项迫切的任务。该文主要对这个区域生物多样性保护的基本情况和发展途径作简要介绍,期待引起各方面的关注。     

Dilated cardiomyopathy caused by tissue-specific ablation of SC35 in the heart

Many genetic diseases are caused by mutations in cis-acting splicing signals, but few are triggered by defective trans-acting splicing factors. Here we report that tissue-specific ablation of the splicing factor SC35 in the heart causes dilated cardiomyopathy (DCM). Although SC35 was deleted early in cardiogenesis by using the MLC-2v-Cre transgenic mouse, heart development appeared largely unaffected, with the DCM phenotype developing 3-5 weeks after birth and the mutant animals having a normal life span. This nonlethal phenotype allowed the identification of downregulated genes by microarray, one of which was the cardiac-specific ryanodine receptor 2. We showed that downregulation of this critical Ca2+ release channel preceded disease symptoms and that the mutant cardiomyocytes exhibited frequency-dependent excitation-contraction coupling defects. The implication of SC35 in heart disease agrees with a recently documented link of SC35 expression to heart failure and interference of splicing regulation during infection by myocarditis-causing viruses. These studies raise a new paradigm for the etiology of certain human heart diseases of genetic or environmental origin that may be triggered by dysfunction in RNA processing.     

家族性高胆固醇血症患者低密度脂蛋白受体基因新突变位点的鉴定

家族性高胆固醇血症(hypercholesterolemia familial,FH)是由于低密度脂蛋白受体(low density lipoprotein receptor,LDLR)基因突变导致的常染色体显性遗传性疾病,临床上表现为多发黄色瘤、高水平血浆LDL、早发性冠心病及有阳性家族史。本研究通过临床症状结合血脂测定诊断出一个FH家系,其纯合子FH患者的血浆总胆固醇水平高达19．05mmol／L,LDL达17．06mmol／L,并有黄色瘤;而杂合子FH患者的血浆总胆固醇水平为7．96mmol／L,LDL为5．55mmol/L,并有心绞痛症状和黄色瘤。我们对该FH家系患者LDLR基因的PCR扩增DNA片段进行测序,发现纯合子FH患者LDLR基因Exon4区域内发生了GAG683GCG突变,即编码LDLR第683位的谷氨酸被丙氨酸替换,而杂合子FH患者该位点呈现杂合突变。此基因型与临床诊断遗传谱完全一致。同时,利用获得Epstein-Barr(EB)病毒转化型人永生淋巴细胞株(EBV-Ls)与荧光探针DiI标记的LDL结合反应,再通过流式细胞仪检测结果显示,具有功能性LDLR的EBV-Ls细胞比例,在纯合子FH患者(7．02％)和杂合子FH患者(62．64％)均比健康对照者(84．69％)低,纯合子FH患者LDLR活性仅为健康对照者的8．29％、而杂合子FH患者LDLR活性约为健康对照者的73．96％,前者呈现非常显著的降低。这些EBV-Ls细胞LDLR的功能变化分析,有力地支持了该FH家系的临床诊断和DNA测序结果。经查阅最新的UMD-LDLR完全版证实,本研究发现鉴定的GAG683GCG突变是人LDLR基因的新突变位点。     

Nucleic acid binding activity of pns6 encoded by genome segment 6 of rice ragged stunt oryzavirus

Rice ragged stunt disease, caused by rice ragged stuntoryzavirus (RRSV), was first discovered in 1976–1977 inIndonesia and Philippines [1]. Subsequently the diseasewas found in most rice-growing countries in south-easternand far-eastern Asia [2] and may inflict heavy loss on thecrop. RRSV is the type species of the genus Oryzavirus in thefamily Reoviridae. The virus particle is icosahedral witha diameter of about 65–70 nm and the genome consistsof 10 double stranded RNA (dsRNA) segm…     

Expression of a modified Cry1Ie gene in E. coli and in transgenic tobacco confers resistance to corn borer

The wild-type Crylle gene from Bacillus thuringiensis was modified for its efficient expression in transgenic plants. Modified Crylle gene (designated as Cryllem) was cloned into prokaryotic expressionvector pET28b and its expression in E.coli was confirmed by SDS-PAGE analysis. Bioassays using crude expression products in E.coli revealed that CrylIem protein had a similar toxicity to corn borer as wild-type CrylIe. CrylIem gene was then inserted downstream of the maize ubiquitin-1 promoter in plant expression vector p3301. Transgenic tobacco plants carrying Cryllem showed insecticidal activity against corn borer.     

一种浓缩噬藻体的反冲超滤技术

噬藻体(Cyanophage)是一类感染蓝藻的病毒,形态上同于噬菌体,近期的研究表明,噬藻体作为水体环境中活跃的动态因子,在控制水体初级生产力和有害藻类水华(Harmful Algal Bloom,HAB)方面可能发挥着重要的作用,甚至影响水体生态系统中食物链的结构,因此研究水体中噬藻体的生理生态学特性对于了解其生态功能是非常重要的,但是由于自然水体中的噬藻体浓度往往较低,难以直接对其进行定性或定量研究,所以对天     

Co-localization of hypocretin-1 and hypocretin-2 in the cat hypothalamus and brainstem

Hypocretin-1 (hcrt-1) and hypocretin-2 (hcrt-2) are two recently discovered hypothalamic neuropeptides. In the present study, using double immunofluorescent techniques, the co-localization of hcrt-1 and hcrt-2 was examined in neuronal soma and fibers/terminals located, respectively, in the cat hypothalamus and brainstem. In the hypothalamus, all hcrt-1 positive neuronal soma also displayed hcrt-2 immunoreactivity. In the brainstem, both hcrt-1 and hcrt-2 antibodies labeled the same fibers/terminals, indicating that hcrt-1 and hcrt-2 co-localize not only in the neuronal soma (hypothalamus) but also in their fibers/terminals (brainstem). If both peptides are released following neuronal activity, then the distinct effects of these peptides in the brain are likely to depend on the types of postsynaptic receptors that are activated.     

两种肚倍型蚜虫之两种同功酶及可溶性蛋白的比较

应用电泳分析方法,对青麸杨上幼锤形信子与长枣形倍子内蚜虫进行了酯酶同功酶、过氧化物同功酶及可溶蛋白质的比较研究。结果表明：经形态学鉴定同为肚倍蚜可致瘿形成纺锤形与长枣形倍子。2种倍形内蚜虫在可溶性蛋白及酯酶同功酶上有较大差异。相异系数分别为02571,0067。说明肚倍蚜种内已出现分化,不同变形体倍子内蚜虫在分子水平上已具有向不同生物型分化的趋势。