用蛋白质及同功酶醋酸纤膜电泳法对近交系小鼠进行遗传监测

本文报道了纯系小鼠遗传质量监测的一种简便而精确的方法——蛋白质及同功酶醋酸纤膜电泳法,并用此法检查确定了我国4个近交系小鼠[津白1(TA1)、津白2(TA2)、615和AMMS1]在Hbb(血红蛋白β链)、Es-1(血清酯酶-1)、Es-2(血清酯酶-2)、Es-3(肾酯酶-3)、Id-1(异柠檬酸脱氢酶-1)和Ldr-1(乳酸脱氢酶调节体-1)6个位点等位基因的分布。同时对我国常用的9个品系共15个封闭群的纯系小鼠在以上6个位点生化标记基因的纯合程度也进行了检查,发现两个封闭群有3个位点的标记基因发生变异。最后对检查结果和方法进行了探讨。     

小鼠胚胎组织、成体组织和胚胎癌细胞酯酶同功酶谱的比较研究

本文比较了129品系小鼠几种胚胎组织及其相应的成体组织的酯酶同功酶谱。几种胚胎组织都可检测到共同的具有相同迁移率的C区酶带和E区酶带。在这些胚胎组织的功能发育过程中,C区酶带被其它区带所取代;E区酶带在成体组织中有的活性降低,有的完全消失。从这些比较分析中可以观察到酯酶同功酶从“胚胎型”向“成体型”的转变。与这些结果相对应,F9-1和B7-2胚胎癌细胞克隆株及来源于早期胚胎细胞的细胞系细胞也都具有酯酶C和E的活性。     

利用结构多样性的对硝基苯酚羧酸酯和脂肪醇乙酸酯评估7个枯草芽胞杆菌酯水解酶的指纹图谱

基于GenBank公布的枯草芽胞杆菌168基因组序列,克隆表达了30个预测的酯水解酶基因。结果发现:其中7个酶对对硝基苯酚酯表现出明显的酯水解活力。它们在α/β水解酶家族中分属5个不同的亚家族。通过显色底物和pH指示剂进行的高通量筛选,分别绘制了这7个酶的底物指纹谱。考察了酶催化手性酯水解反应的对映选择性,结果表明:对硝基苄基酯酶PnbA和S-脱乙酰化酶Cah对手性醇的乙酸酯具有较广的底物谱,而PnbA和羧酸酯酶Nap分别对DL-薄荷醇乙酸酯和2-氯-1-苯乙醇乙酸酯/2-萘乙醇乙酸酯有极好的对映选择性(E>200)。此外,发现酯酶YitV催化2-氯-1-苯乙醇乙酸酯水解的反应遵循反-Kazlauskas规则。     

坝上长尾鸡pmel基因核心启动子的鉴定

为探明坝上长尾鸡的前黑素小体蛋白(Pre-melanosomal protein,Pmel)基因核心启动子区,首先构建了双荧光素酶表达载体,通过脂质体瞬时转染鸡胚成纤维细胞DF1,并利用双荧光素酶检测试剂盒进行启动活性检测。成功克隆了坝上长尾鸡pmel基因5?侧翼区片段1268bp,预测启动子区(-1200–+68)含有2个CpG岛和多种转录因子结合位点,构建了9个含有不同长度pmel基因启动子片段的表达载体及1个核心启动子区突变载体,说明鸡pmel基因启动子的核心区域为-840–+68bp,其中-840–-590bp和-525–-266bp区域为正调控区,-590–-525bp区域为负调控区,多态位点(-456、-435、-410、-374和-341)对pmel基因启动子活性有较大影响。     

菘蓝属植物的同工酶分析及其系统学意义

采用聚丙烯酰胺凝胶电泳,比较了菘蓝属（Isatis L.)5种2变种1多倍体品种及1外类群种共计20个样本的酯酶同工酶和超氧化物歧化酶同工酶的酶谱差异,并运用数量分类学的原理和方法对酶谱数据进行了聚类分析。20个样本的酯酶同工酶酶谱共有18条酶带,可分为慢带区（A区）、中带区（B区）和快带区（C区）3个区,其中A区的Rf0.09酶带为所有样本共有,而B区和C区不仅酶带数多,而且活性较强,并表现出很大差异。20个样本的超氧化物歧化酶同工酶酶谱有8条酶带,略有差异。聚类分析结果表明,20个样本被明显分成10组,与形态性状分类结果基本一致。利用酶带的有无、酶带的活性差异以及聚类分析结果,可以初步作出菘蓝属类群间亲缘关系的判定。     

八倍体小黑麦的酯酶同工酶

在小黑麦的酯酶同工酶研究中,一些报道指出,六倍体小黑麦的胚乳产生5条快速移动带,带1、2和3来自小麦,带5来自黑麦,带4是杂种带;小麦和黑麦胚乳样品机械混合物的酶谱中,只有1、2、3和带5。在比较六倍体小黑麦(AABBRR)和某些八倍体小黑麦(AABBDDRR)时,我们看到在两者的酯酶同工酶酶谱中都有上述E_1区5条标志带。同时,我们也发现,有一些八倍体小黑麦表现出另外     

中华按蚊和雷氏按蚊嗜人亚种八种同工酶的遗传学分析及其亲缘关系的研究

本文对中华按蚊和雷氏按蚊嗜人亚种及它们的杂种后代的同工酶进行电泳分析。结果表明,二蚊种的酯酶均有4个基因,并存在遗传上的多态性。利用酯酶抑制谱也肯定了遗传分析的结果。磷酸甘油脱氢酶(GPD)于中华按蚊有2个基因,雷氏按蚊嗜人亚种仅1个基因。碱性磷酸酯酶(APH)、过氧化物酶(POD)在中华按蚊都较在雷氏按蚊嗜人亚种多出1条酶带。乳酸脱氢酶(LDH)、辛醇脱氢酶(ODH)和苹果酸脱氢酶(MDH)的酶带二蚊种相同。酸性磷酸酯酶(ACP)在二蚊种内都未能显示清晰酶带。这些事实指出二者是关系很近的近缘种。对不同地理区域中华按蚊、雷氏按蚊嗜人亚种和贵阳按蚊的酯酶比较也获得一些关于它们演化关系的信息,并发现这3个种的具有分类特性的酯酶带。     

D染色体组对小麦酯酶同工酶的影响

应用垂直平板聚丙烯酰胺凝胶电泳,分析了灌浆期种子胚乳的酯酶同工酶。结果表明,具有 D 染色体组的节节麦、偏凸山羊草和粗厚山羊草都有1条迁移率相同的 E_(1-1)带。在普通小麦(AABBDD)和二粒系小麦(AABB)的酶谱中,E_(1-1)和 E_(1-2)各自由两条紧密靠近的带构成。这两个种的 E_3区都有5条带。虽然两个种的小麦之间这些带的迁移率没有差异,但是,其活性不同,而且表现出规律性的变化。二粒系和普通小麦之间正反交杂种的酶谱大多倾向于母本类型,表现出 D 染色体组的剂量效应。     

中国西部麦红吸浆虫(双翅目:瘿蚊科)酯酶同工酶与种群遗传结构研究(英文)

本文用PAGE方法测定了我国西部麦红吸浆虫Sitodiplosismosellana (G啨ｈｉｎ) 3个地理种群酯酶同工酶 ,分析了其遗传规律及种群的遗传结构。采样地点有春麦区的皋兰县 (36.3°N ,1 0 3.9°E)和武威市(37.9°N ,1 0 2 .6°E)及冬麦区的长安县 (34.1°N ,1 0 8.9°E)。结果分析认为该酶受两个基因位点控制 ,命名为Est 1和Est 2。Est 1可能为质体基因 ,其酶谱为所有带中移动最快的一条 ,每个个体都有。Est 2为重复基因位点 ,共观察到 8个等位基因 ,在所有种群中表现为 8条带 ,依其迁移速度命名为a、b、c、d、e、f、g、h。Est 2在每个个体中表现 1 - 4条带 ,且为一多态位点 ,因此该等位酶可作为一个稳定的遗传标记。在所有研究种群的个体中 ,共观察到 1 9种酶谱类型。在冬麦区长安种群中个体酶谱类型多达1 7个 ;春麦区个体酶谱类型少 ,在皋兰种群内有 5个、武威种群内有 4个。在所有的种群中 ,以d、e、g 3个等位基因的频率最高。冬麦区长安种群内有 8个等位基因、而春麦区种群仅有 3个。通过对Est 2单个基因位点的遗传一致度和聚类分析表明 ,春麦区两种群亲缘关系较近 ,且都与冬麦区种群较远。上述所有分析显示麦红吸浆虫有一定程度的种下分化 ,遗传漂移可能是引起该分化的主要原因。不同种群间有可能发生过     

黄淮区粳稻抗稻瘟病基因Pi-ta、Pi-b、Pi54、Pikm的分子检测

利用水稻稻瘟病抗病基因Pi-ta、Pi-b、Pi54 和Pikm的功能标记对2016年山东省水稻中晚熟组区试、机插秧组区试的32个参试品系及连云港农业科学院科企水稻联合体黄淮粳稻区试16个品系进行了分子标记检测,结合稻瘟病抗性接种鉴定,对基因型与表型进行相关性分析。结果表明48个品种中携带Pi-ta、Pi-b、Pi54和Pikm抗性基因的品种数分别为15个、25个、26个和21个,其中鲁资稻7号、连粳14JD24含有4个基因的抗性等位基因,YS-6-6、济稻1号、D400等13个品种分别含有3个基因的抗性等位基因,临稻10号、丰稻2号、天和糯303等8个品种不含抗性等位基因。稻瘟病鉴定结果表明,48份品种中,济稻1号、圣稻072、连粳14JD24等4个品种表现中抗（MR）;临稻10、YS-6-6、圣稻053等26个品种表现中感（MS）;晶稻180、临13-105、圣稻504等15个品种表现感病（S）;H11-15、润农9号、晶稻160表现高感（HS）。Pi-ta、Pi-b、Pi54、Pikm 4个抗性基因已在黄淮区粳稻抗稻瘟病育种中得到广泛应用。其中Pikm与稻瘟病抗性综合指数存在显著相关性（r=0.477 5,P<0.01）。     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Entwicklungsgeschichte und Ultrastruktur von Pollenkitt und Exine bei nahe verwandten entomophilen und anemophilen Angiospermensippen derAlismataceae,Liliaceae, Juncaceae,Cyperaceae, Poaceae undAraceae

Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.

     

Identification and Characterization of the First Equine Parainfluenza Virus 5

正Dear Editor,Parainfluenza virus 5 (PIV5), known as canine parainfluenza virus in the veterinary field, is a negative-sense,nonsegmented, single-stranded RNA virus belonging to the Paramyxoviridae family (Chen 2018). The virus was first reported in primary monkey kidney cells in 1954 (Hsiung1972), then it has been frequently discovered in various     

Pathogenic Characterization and Full Length Genome Sequence of a Reassortant Infectious Bursal Disease Virus Newly Isolated in Pakistan

<正>Dear Editor,Infectious bursal disease (IBD) is one of the most important diseases of the poultry. The IBD virus (IBDV), a nonenveloped virus belonging to the Birnaviridae family with a genome consisting of two segments of double-stranded RNA (segments A and B), targets B lymphocytes of bursa of Fabricious leading to immunosuppression. In Pakistan,poultry farming is the second biggest industry and IBD is the second biggest disease threating the poultry sector.However, there is limited genome information of IBDV