二化螟隐花色素基因cryptochrome1和cryptochrome2的克隆与表达谱分析

隐花色素基因(cryptochrome,简称cry)是一类生物钟基因,参与生物体昼夜节律调控。本实验克隆了二化螟2个隐花色素基因,分别命名为Cs-cry1和Cs-cry2(Genbank登录号分别为HG780135和KF977409),其分别包含1605 bp和2289 bp的开放阅读框,分别编码由534和762个氨基酸组成的蛋白;Cs-cry1与其它鳞翅目昆虫cry1的相似性较高,而Cs-cry2与其它鳞翅目昆虫cry2的相似性较高,这与系统进化分析结果相一致;半定量RT-PCR研究表明Cs-cry1和Cs-cry2基因在二化螟成虫触角、头、雄、腹、足和翅等不同组织中均有表达。实验结果为二化螟昼夜节律分子机制研究提供了理论依据。     

苏云金芽孢杆菌及其在害虫防治上的应用(综述)

苏云金芽孢杆菌 (Bacillusthuringiensis,简称Bt)自 1 90 1年发现以来 ,一直在微生物学、昆虫学和生物化学等方面受到研究者的关注。由于Bt能形成对许多昆虫具特异性毒力的杀虫蛋白 ,因此从 1 959年开始Bt已被制成杀虫剂防治鳞翅目害虫。近 1 0年来 ,随着分子生物学和遗传工程技术的成熟和发展 ,使人们增加了有关晶体形成的分子生物学知识。Bt的杀虫活性主要是其能产生含有杀虫晶体蛋白 (ICPs)的伴孢晶体。一些杀虫蛋白基因 (又称cry基因 )已经成功用于转基因抗虫植物中。本文将从Bt微生物学、Bt制剂在害虫防治中以及Btcry基因在转基因抗虫植物中的应用等方面作一综述。     

鸭疫里默氏杆菌的GAPDH同源体:一种有生物活性的胞外蛋白(英文)

研究目的:对鸭疫里默氏杆菌的三磷酸甘油醛脱氢酶(GAPDH)进行鉴定和生物学特征分析。创新要点:首次证实鸭疫里默氏杆菌具有GAPDH的同源体酶(RaGAPDH)是一种无信号肽和跨膜区的胞外蛋白酶,具有将3-磷酸甘油醛转化为1,3-二磷酸甘油酸的活性,可与纤维蛋白溶酶原及纤维蛋白原发生结合,推测该酶可能是鸭疫里默氏杆菌的一个新发现的毒力因子。研究方法:1.对分离自重庆、四川地区的鸭疫里默氏杆菌(表1)菌体细胞表面蛋白(图1a)和CZ2、SC12、YC1三株菌胞外蛋白(图1b)的GAPDH活性进行检测,对其编码基因进行PCR鉴定(图2)和克隆测序分析(图3);2.采用染色体步移技术获得CZ2的GAPDH编码基因进行原核表达(图4a和4c);3.以获得的具有活性的重组GAPDH为抗原,制备鼠原多克隆抗体并采用Western-blot方法对鸭疫里默氏杆菌的胞外分泌蛋白进行检测分析(图4b);4.采用固相配体结合试验检测RaGAPDH与纤维蛋白溶酶原、血纤维蛋白原、肌动蛋白和纤连蛋白的结合作用(图5)。重要结论:鸭疫里默氏杆菌具有三磷酸甘油醛脱氢酶同源体,具有GAPDH活性,能与纤维蛋白溶酶原和血纤维蛋白原结合,可能是其重要的毒力因子。     

牛奶中苏云金芽胞杆菌的分离与鉴定

采用醋酸钠-抗生素分离法对超市牛奶样品进行苏云金芽胞杆菌(Bacillus thuringiensis,Bt)的分离,获得2株Bt菌株,分别命名为BtBRC-LJ1和BtBRC-LJ2。利用PCR方法对BtBRC-LJ1和BtBRC-LJ2菌株hblD和nheC肠毒素基因的分布进行检测。结果显示,这2个菌株均含有这两种肠毒素基因。     

高致病性禽流感H5N1血凝素蛋白表达及活性测定

通过PCR扩增高致病性禽流感H5N1的HA和HA1基因片段,利用原核表达系统表达重组HA和HA1蛋白,并用SDS-PAGE,Western-blotting和血凝试验进行重组HA蛋白的鉴定和血凝活性鉴定.结果表明,经过HA蛋白胞外段分析、重组载体的酶切鉴定得出的重组HA蛋白,在血凝试验中能与HA特异性抗体结合,并有较高的血凝活性.利用表达载体pET42a表达AIV-H5亚型的HA基因,为进一步利用重组蛋白研制AIV-H5抗体的ELISA检测方法,研制抗AIV-H5亚型的单克隆抗体提供基础.     

奶牛CD4基因选择性剪接的鉴定

目的:通过检测奶牛CD4基因选择性剪接,为研究CD4基因的结构和功能打下基础。方法:采集奶牛尾静脉血,提取血液总RNA后反转录成cDNA。通过反转录PCR扩增和测序,以鉴定CD4基因剪接体和单核苷酸多态性。结果:通过序列比对分析,发现奶牛CD4基因外显子8处存在缺失,扩增的两种CD4mRNA序列长度相差122bp(整个外显子8缺失)。另外,在牛CD4基因外显子8处检测到1个碱基突变(C/A)。结论:奶牛CD4基因发现两种相差外显子8的剪接体,并检测到1个SNP。     

大豆生育期基因E1～E4研究概述

大豆E基因家族对其生育期调控起着重要作用,明确不同大豆品种资源的E基因变异类型对提前预测大豆亲本和子代的生育期具有重要价值。随着分子生物学技术的不断发展,众多大豆E基因家族成员被鉴定,尤其是作为主效基因的E1～E4,其多个变异类型被陆续发现和鉴定。本文概述了E1～E4基因的特征、不同基因型及与生育期之间的关系,对今后如何高效开展大豆生育期预测及遗传改良提出展望。     

想长寿的人有指望了美找到人类长寿基因区域集中于人类第4染色体

美国波士顿儿童医院的分子遗传学家库凯勒博士与哈佛大学老年病学家佩尔斯8月27日在美国科学院的新闻发布会上宣布,他们在人体第4染色体上发现了长寿基因区域. 他们对137对90岁以上的同胞兄妹的基因进行了研究.科学家在他们的染色体组上共设置了400个标记,通过DNA鉴定,发现第4染色体上有一个数量约为100到500个的基因群,将其与已知功能的基因进行比较后,科学家确信其中含有一个或多个长寿基因.     

不同线粒体基因作为DNA条形码鉴定按蚊的比较分析

蚊虫是最为重要的医学昆虫之一,准确鉴定其种类是防控的重要基础,但基于形态学鉴定困难较多。线粒体基因组序列获取便捷、已公布数据全面,作为DNA条形码开展分子鉴定具有突出优势。为进一步评估不同线粒体基因序列作为DNA条形码在蚊科昆虫鉴定中的作用,本研究以按蚊属为例,选取在GenBank数据库中线粒体全基因组序列公布最多的5种,每种随机下载5条序列,通过进化速率、遗传距离、条形码间隙和系统发育分析,比较了线粒体全部13个蛋白质编码基因分别作为DNA条形码鉴定种类的可靠性。结果表明按蚊线粒体的13个蛋白质编码基因中,ND5基因进化速率最快,而COI基因最为保守。除COIII基因外,其余基因均可作为DNA条形码开展分子鉴定,但其中ND4L基因的条形码间隙不显著,可能存在鉴定不准确的情况。剩余线粒体基因中,ATP8、COI、COII、CytB和ND5基因间隙显著且在种内和种间均具有较强的稳定性,优先推荐选用为DNA条形码,ATP6、ND1、ND2、ND3、ND4和ND6基因则存在种内或（和）种间不保守的情况,可以作为备选序列。研究结果为科学选用DNA条形码序列进行蚊科昆虫的鉴定提供了参考依据。     

弓形虫主要表面抗原1截短型片段的克隆与表达

为构建弓形虫主要表面抗原1(SAG1)的原核重组表达质粒并获得重组表达蛋白,采用聚合酶链反应(PCR) 从弓形虫RH 株基因组DNA中扩增SAG1基因,经克隆和测序后,亚克隆至原核表达载体pGEX-4T-1,转化大肠杆菌BL21,PCR和双酶切鉴定阳性菌株,表达产物用SDS-PAGE和Western blot进行鉴定观察其诱导的抗体应答.结果表明,PCR扩增出SAG1基因的特异片段,获得的阳性克隆序列与Gen Bank中的SAG1基因序列一致,SAG1基因被亚克隆到表达载体pGEX-4T-1,在BL21中表达了SAG1,表达的蛋白能被弓形虫感染兔血清识别.以上结果说明,已成功构建了弓形虫SAG1的重组表达质粒,在大肠杆菌中表达的SAG1具有良好的免疫学活性.     

几株Bt菌株对紫外线的抗性探讨

采用不同照射时间的紫外光（UV）对1株野生型Bt菌株及3株Bt菌株Bt001、Bt200、Bt087进行照射处理后再置于双碟上培养16h，结果表明，Bt野生菌株在UV处理3min后已基本全部失活，而Bt001、Bt200、Bt087在UV处理8min后仍有活性。从UV处理时间的长短及平板上出现菌落数的多少得知，尽管菌株Bt001、Bt200、Bt087对UV的抗性都比野生Bt菌株强得多，但并不相等。其中，Bt200相对弱些，UV处理9min后已无菌落；Bt087最弱，UV处理8min后已无菌落；而菌株Bt001对UV的抗性最强，UV处理13min后仍有菌范出现。这说明不同的Bt菌株，其遗传背景是不同的。另外，Bt001经紫外线照射9min，培养16h后发现有9个菌落发生明显的变异，菌落呈棕黄色，菌落明显比原始菌落小。涂片，油镜下观察其菌体要比原始菌体小，此为明显发生突变的菌株。     

电激法转移质粒扩大苏云金杆菌杀虫谱

应用高压电激法,把载有表达不同杀虫谱晶体蛋白基因的两种质粒同时转入晶体缺陷型的BT菌株,或者把载有表达单一晶体蛋白基因的质粒转入不同亚种且产生晶体的天然BT菌株中,通过生物测定法,快速而简便地筛选出杀虫谱扩大及杀虫毒力提高的重组菌株。所筛选到的菌株产生的伴孢晶体,同时对鳞翅目及双翅目昆虫幼虫有毒杀作用,并且重组菌株所产生的伴孢晶体的形状有异于其出发菌株的伴孢晶体。     

Cognitive Set and Coping Strategy Affect Mothers' Sensitivity to Infant Cries: A Signal Detection Approach

We used Signal Detection methodology to examine how cognitiveset affects mothers' response to an infant cry. We asked whether a cry from a "difficult" versus an "easy" infant would elicit a change in sensitivity or response bias in mother processing of these cries. Thirty-eight mothers of 4- to 6-month-old infants participated in a Signal Detection task in which they were asked whether they could detect differences between a standard cry and 1 to 4 cry variants. Cry variants differed from the standard cry in small, systematic changes in fundamental frequency. The task was conducted in 2 parts; each part constituted a condition wherein mother received a cognitive set manipulation that labeled the identical cry as coming from either a'difficult'or an "easy" infant. An increase in mothers' sensitivity was associated with the "difficult" infant cognitive set. We examined as well how a coping strategy(illusion of control) affected cry signal processing. Mothers who Exhibited high illusory control were least -sensitive in detecting differences between cries. Two information-prcessing, measures response time and heart rate, were also collected and showed that greater sensitivity was associated with more efficient processing of the cry signal.     

The effects of within-group and between-group methodologies in the study of perceptions of infant crying

Recent studies have indicated that various infant cry patterns can be reliably distinguished when directly compared with other infant cry patterns. The purpose of this study was to compare the effects of this within-group method of cry presentation (in which listeners are exposed to 2 types of cry patterns) with the effects of a between-group methodology (in which listeners are exposed to only 1 type of infant cry pattern). 4 groups of adult listeners rated the tape-recorded cries of low- and high-risk infants on 4 Likert-type scale items during experimental phases. In phase 1, subjects were exposed to either the cries of low-risk or high-risk infants but not both. In phase 2, subjects were exposed to both low-risk and high-risk infant cries. In phase 3, subjects were exposed to the cries they heard in phase 1. Whereas all scale items differentiated the low- and high-risk infant cries during the within-group analyses of phase 2, all scale items did not differentiate low- and high-risk infant cries during the between-group phase of the experiment. The specific pattern of results indicate that within-group methods of cry presentation accentuate the perceptual distance among cry types and may actually create many reliable differences that would not be found in between-group comparisons.     

Adult perceptions of pain and hunger cries: a synchrony of arousal

180 male and female nonparent adults rated tape-recordings of the initial, middle, and final 10-sec segments of pain and hunger cries on 4 7-point Likert-type scale items describing how urgent, arousing, aversive, and sick the cry segments sounded. Multivariate analyses of variance showed that the final segment of the pain cry was perceived as less urgent, arousing, and aversive than the initial and middle segments. The hunger cry was perceived as increasingly more urgent, arousing, and aversive from the initial to the middle to the final cry segments, with the final segment receiving higher ratings than the final segment of the pain cry. The middle segment of both cries was the most sick sounding. While females were more aroused than males as the hunger cry intensified, and females were less aroused than males as the pain cry subsided, the initial segments of the pain cry were particularly potent stimuli to both males and females. These results suggest that different segments of cries resulting from the same stimulus provide different messages that communicate the presumed level of infant arousal.     

江苏省苏北地区土壤苏云金杆菌及其杀虫特性

根据不同的土壤类型,从江苏省苏北地区6市采集土样422份,分离出苏云金杆菌76株.血清学分析表明,它们分属于H_3、H_7、H_10、H_21和H_43型,另一株为自凝菌.通过对76个分离株的生物毒力测定,筛选出4林对赤松毛虫、小菜蛾、玉米螟等具有高毒力的菌株,为开发高效苏云金杆菌杀虫剂提供了重要的菌种资源.     

5 种药剂对台湾乳白蚁( Coptoterme sformo sanus) 的室内生物测定

在室内测定了5 种药剂对台湾乳白蚁的传毒性. 结果表明,吡虫啉作用迅速,用药后1 、2 天的死亡率均达36 %以上;巴丹作用十分缓慢,第9 天的最大死亡率为12139 %. 阿维菌素、Bt 对台湾乳白蚁的作用,与对照药剂灭蚁灵相近,药后4 、5 天出现死亡高峰,死亡率均达32 %以上,可作为白蚁灭治药物,进一步进行探讨研究.     

Adults'' Tolerance of Cries: An Experimental Investigation of Acoustic Features

Variations in the aversiveness of a newborn's distress cry were examined using experimental manipulation of 3 acoustic features of the cry (fundamental frequency, intonation, spectral complexity) and of the information given to subjects about the infant's health status. The subjects (N = 164 medical students) were allowed to control the sound pressure level (range: 50 dB [A]-105 dB[A]) of the different cry versions by repeatedly pressing a button (operant titration). For the nonmanipulated (original) cry version, the accepted sound pressure level decreased as fundamental frequency increased at above 610 Hz. This effect was modified by experimental manipulation of spectral complexity as well as intonation. A preference of intonated cries over monotonous cries was most pronounced between 534 and 686 Hz. Significant interactions of the information variable with the intonation and the complexity variables suggest that the listener's reaction to certain physical cry characteristics can be altered substantially by inducing different cognitive sets.