鱼类免疫球蛋白生物合成的遗传控制研究综述

真骨鱼重链IgM恒定区基因由CH1～CH44个外显子所编码,以IgM分泌型表达,其跨膜域由2个外显子所编码,它以淋巴细胞膜受体形式被利用,TM1外显子被直接剪接到CH3外显子,而不是在CH4外显子内,这种不寻常的剪接方式导致产生Cμ4区的膜IgM。真骨鱼IgD重链除包括分泌型或膜结合型的C末端外,这个重组分子还包括1个重组的可变区、μ链的第1个恒定区及7个恒定区。IgD(δ)重链基因恰好位于IgM(μ)基因下游,第1个恒定区μ外显子被剪切形成δ转录本。     

中国大耳白肉兔IFN-γ、IL-2和IL-4基因的克隆测序与进化分析

实验应用反转录-聚合酶链式反应(RT-PCR)技术,在国内首次从ConA诱导培养的中国大耳白肉兔外周血淋巴细胞总RNA中扩增得到IFN-γ、IL-2和IL-4基因,并将其克隆到PGEM-T载体中,经菌落PCR鉴定、序列测定及序列分析,结果表明:①经克隆得到的IFN-γ基因(序列号:DQ852341),与Genbank中已登录的欧洲兔IFN-γ基因(序列号:AB010386)的核苷酸序列和推知氨基酸序列的同源性均为100%;与其他哺乳动物如犬、猫、人、猪、牛、羊、马、大熊猫和鼠等的核苷酸同源性在63.0%(鼠)～77.6%(人)之间;编码氨基酸同源性在41.7%(鼠)～65.7%(人)之间;②扩增得到的IL-2基因(序列号:DQ852342),与Genbank中已登录的欧洲兔IL-2基因(序列号:AF068057)的核苷酸序列和推知氨基酸序列的同源性分别为99.6%和100%;与其他哺乳动物如犬、猫、人、猪、牛、羊、马、大熊猫和鼠等的核苷酸同源性在64.8%(鼠)～86.0%(人)之间;编码氨基酸同源性在55.7%(鼠)～80.1%(人)之间;③扩增得到的IL-4基因(序列号:DQ852343),与Genbank中已登录的欧洲兔IL-4基因(序列号:AF169169)的核苷酸序列和推知氨基酸序列同源性均为100%;与其他哺乳动物如犬、猫、人、猪、牛、羊、马、大熊猫和鼠等的核苷酸同源性在57.0%(大熊猫)～69.8%(人)之间;编码氨基酸同源性在43.0%(鼠)～53.6%(人)之间。用这3个基因分别构建的进化树结果都表明,兔与人的亲缘关系相对较近,与鼠的亲缘关系最远,这与传统的分类地位基本吻合,即兔与鼠应分别归为兔形目和啮齿目动物。     

乌鳢免疫球蛋白M重链和免疫球蛋白轻链的克隆与特征分析

应用RACE-PCR方法克隆并鉴定了乌鳢免疫球蛋白M(i mmunoglobulin M,Ig M)重链(H)和免疫球蛋白轻链(L)全长cDNA。乌鳢IgH cDNA全长1 912个核苷酸(nt),包含1 797 nt的开放阅读框,编码598个氨基酸(aa)。IgH恒定区(CH)均包含1对保守的半胱氨酸残基形成链内二硫键,其中CH1区氨基末端存在保守的半胱氨酸残基与轻链形成链间二硫键,4个推测的N-糖基化位点(NXT和NXS)则分别位于CH1、CH2和CH4。序列比对发现乌鳢IgHCH1与CH2交界处氨基酸序列的插入使铰链区肽段较其他硬骨鱼IgH长,此外IgH CH4区羧基末端参与单体间聚合的半胱氨酸被赖氨酸替换,这反映乌鳢IgH分子结构的特异性。序列相似性比较显示乌鳢IgH与点带石斑鱼、黑鳍冰鱼、牙鲆、虹鳟的相似性依次为55%、50%、45%和36%,与斑马鱼类的相似性较低(为28%)。乌鳢IgL cDNA全长941 nt,包含729 nt的开放阅读框,编码242个aa。轻链可变区(VL)和恒定区(CL)均包含保守的半胱氨酸,形成链内和链间二硫键。序列比对分析表明乌鳢IgL与五条鰤和花狼IgL的相似性为78...     

果子狸苦味受体Tas2R2基因的克隆与序列分析

采用PCR和克隆测序方法首次从果子狸基因组中获得一全长为1 037 bp的苦味受体Tas 2R2基因DNA序列.该序列含有完整的1个外显子(无内含子),大小为915 bp,编码304个氨基酸残基.其蛋白质等电点为9.84,分子量为34.87 ku.高级结构预测显示果子狸Tas2R2蛋白由4个胞外区、7个跨膜区和4个胞内区组成,该蛋白上含有N糖基化位点、丝氨酸磷酸化位点、色氨酸磷酸化位点各3个和酪氨酸磷酸化位点1个.亲水性/疏水性分析表明,果子狸Tas2R2蛋白质为疏水性蛋白,其亲水性区段所占比例较小.种间同源性比较显示,果子狸Tas 2R2基因与猫、犬、大熊猫、牛、马、黑猩猩和小鼠的eDNA序列同源性分别为93.0％、89.4％、89.9％、85.4％、85.9％、84.6％、72.2％;氨基酸序列同源性分别为88.8％、81.1％、83.2％、75.9％、77.8％、75.5％、61.3％.果子狸、猫、犬、大熊猫、牛、马、黑猩猩和小鼠的Tas 2R2基因编码序列构建的进化树表明果子狸与猫的亲缘关系最近.     

罗非鱼免疫球蛋白（IgM）重链基因全长cDNA序列分析

从已经构建的罗非鱼白细胞cDNA文库中测定获得罗非鱼免疫球蛋白（IgM）重链的eDNA序列,全长1885bp,有一个完整ORF阅读框长1770bp,5’UTR为29bp,3’-UTR为86bp,编码588个氨基酸。罗非鱼与大黄鱼、斜带石斑鱼、南极鳕鱼、乌鳢、鳜鱼、伯氏豚[鱼叚]虎鱼、牙鲆、花狼鱼、硬头鳟的IgM重链氨基酸序列有较高的同源性,最高达到69％,表明已经获得罗非鱼IgM重链基因;对所得氨基酸进行二级结构预测发现,罗非鱼IgM重链基因全长cDNA序列所编码的氨基酸分子量为41453．94Da。该试验结果为罗非鱼IgM重链基因功能的实验性鉴定工作奠定了基础。     

猪流行性腹泻毒株S基因分离鉴定及序列分析

根据NCBI上传的猪流行性腹泻病毒(porcine epidemic diarrhea virus,PEDV)[GenBank:JN547228(CH/S)],设计引物对阳性病料进行鉴定并回收,与pMD18-T构建重组载体并测序。对猪流行性腹泻病毒的基因多样性及序列保守性进行分析,一是以经典毒株为主,包括CV777、KPEDV-9和CH/S株等为代表的G1基因型,另一种是以近几年分离的毒株为主,包括HB3-CH2012、CXHZ-CH2013、HNCZ-CH2013等为代表的G2基因型。基因同源性分析比较结果表明,这4株PEDV之间的序列同源性为97.6%～100.0%,与经典株CV777的同源性为92.7%～92.8%。同源分析显示,PEDV不同毒株间的基因同源性仍高度相似,但PEDV流行毒株已呈现进化分支的趋势。     

猪IgG H链基因CH2-CH3的克隆和分析

根据已发表的猪IgG H链序列,设计了1对通用引物,从猪外周血淋巴细胞提取总RNA,经RT-PCR扩增IgG H链基因CH2-CH3序列,并克隆入pMD18-T Simple载体,转化大肠杆菌DH5α感受态细胞,经SalI和XbaI双酶切鉴定,筛选出阳性克隆。核酸序列测定分析表明,IgG H链基因CH2-CH3序列全长为669 bp,编码CH2-CH3的221个氨基酸和J区的1个脯氨酸。利用DNASTAR软件将其与猪IgG H链各CH2-CH3序列进行比较,发现其与U03778-1、U03779-2a、U03780-2b、U03781-3、U03782-4的核苷酸序列同源率分别为92.1%、98.4%、98.5%、93.0%和97.2%,推导的氨基酸序列同源率分别为86.5%、96.4%、96.5%、87.0%和94.2%。经进化树分析提示,该序列可能为一个新的亚型。     

3株传染性支气管炎病毒蛋鸡源河南株的S1基因序列分析

为了解河南省致蛋鸡产蛋量下降的传染性支气管炎病毒(IBV)的流行特征,从河南南阳、信阳和安阳等市的发病鸡场中鉴定出3株IBV,分别命名为CK/CH/HN/NY1206/2017、CK/CH/HN/XY911/2017和CK/CH/HN/AY119/2018,并应用RT-PCR技术对3个IBV分离株的S1基因进行扩增与序列分析。结果显示,3个IBV分离株S1基因全长都为1 617 nt,编码539 aa,并且都属于基因型4/91(CHⅡ);CK/CH/HN/NY1206/2017株S1基因裂解位点为RRSRR,CK/CH/HN/XY911/2017株S1基因裂解位点为RRSRR,CK/CH/HN/AY119/2018株S1基因裂解位点为RRFRR;3个分离株间核苷酸序列及其推导的氨基酸序列具有较高同源性,与位于同一基因型的参考毒株间同源性较高,与我国使用的Mass型常规疫苗H120和H52株的核苷酸和氨基酸同源性最低,分别仅为78.3%～78.4%和74.8%～75.4%,与4/91(CHⅡ)型疫苗4/91株的核苷酸和氨基酸同源性较高,分别达到94.7%～99.3%和93.9%～98.1%。综上,河南省致蛋鸡产蛋量下降的IBV流行株基因型相对统一,使用4/91(CHⅡ)型疫苗应可提高蛋鸡抗IBV的效率。     

犬γ-干扰素基因的克隆、序列分析及蛋白质结构预测

根据Gen Bank上犬γ-干扰素基因(IFN-γ)序列(序列号WO318193),利用Primer 5.0软件设计特异性引物,应用RT-PCR技术从100μg/ml Con A刺激24 h后的犬外周血淋巴细胞总RNA中扩增出γ-干扰素基因,测序后应用DNAStar软件对克隆的犬γ-干扰素基因进行序列分析,并与Gen Bank上发表的犬、牛、大熊猫、鸡、牦牛、人、猪、野猪、斑马鱼、土拨鼠等的IFN-γ基因序列进行同源性比较。结果显示,克隆的犬IFN-γ基因大小501 bp,编码166个氨基酸,与犬、牛、大熊猫、鸡、牦牛、人、猪、野猪、斑马鱼、土拨鼠IFN-γ基因的核苷酸序列同源性分别为98.4%、81.6%、26.1%、26.1%、22.7%、22.7%、80.8%、81.0%、28.5%和25.0%;氨基酸序列同源性分别为95.8%、72.5%、5.4%、5.4%、6.6%、6.6%、68.9%、69.5%、5.4%和5.4%。运用DNAstar软件对犬γ-干扰素进行蛋白结构预测的结果显示,犬γ-干扰素蛋白含有10个α-螺旋、9个β-折叠、11个β-转角和5个无规则卷曲。     

大白菜PHK4基因cDNA3'端序列的克隆及分析

采用 3'RACEcDNA末端扩增技术,克隆出大白菜PHK4基因3'端cDNA序列.该序列长810bp,其中编码区序列546bp,编码181个氨基酸,其编码序列、氨基酸序列与拟南芥AHK4基因的同源性分别为90%和96%,说明PHK4基因与AHK4基因编码区的同源性较高,而PHK4基因3'UTR区与AHK4基因3'UTR区的同源性为52%,远低于编码区.     

Web2.0,以个人为中心的互联网时代的到来

本文介绍了Web2．0的知识和背景，对Web2．0出现的基础以及典型技术和应用作了阐述，同时对其作出了前景展望。     

盐胁迫对葡萄苗期多胺和激素代谢的影响

【目的】 研究盐胁迫条件下,葡萄叶片中多胺含量、多胺氧化酶、多胺合成酶活性以及激素的动态变化,研究不同盐胁迫强度对多胺类物质及激素代谢的影响。【方法】 采用盆栽基质培养模拟盐胁迫环境,设置4个NaCl处理梯度:0 (CK)、1、2和3 g/kg。多胺和激素含量的测定采用高效液相色谱法,多胺合成及分解酶活性的测定采用紫外分光光度计比色法。【结果】 盐胁迫处理后,葡萄叶片中多胺含量和脱落酸含量较对照而言显著增加,玉米素含量显著降低,随胁迫时间的延长,Put、Spm、Spd、ABA以及PAO、DAO、ADC、ODC、SAMDC活性均呈先上升后下降趋势,在10 d及10 d后达到峰值。ZT呈逐渐下降的趋势,并随胁迫强度增大而减小;进行显著性分析后,叶片中多胺含量与Put、Spm、Spd含量呈极显著正相关,DAO、ADC、ODC活性与Put含量呈显著正相关,PAO与SAMDC活性与Spm和Spd含量也呈极显著正相关。【结论】 3种多胺经酶的合成代谢后和激素共同缓解葡萄苗所遭受到的盐胁迫,期间主要发生作用的是多胺合成酶,盐胁迫下多胺与激素含量之间的变化关系也十分密切。     

市级综合气象信息分析与管理系统的设计与实现

以抚顺地区3个国家基本站50余年气象资料为依托,采用Microsoft Excel工作表实现由气候和农业气候2部分构成的气象与农业综合信息处理系统的基本思路、方法、内容、用途和使用情况。为了实现气候分析及应用的科学化、客观化、系统化、规范化、程序化及连续化的业务目标,按业务流程设计与实现的,包括资料处理、气候趋势模拟、气候预测、气候鉴定、季节性信息化处理、农作物产量预报、气候生产潜力分析等一系列内容在内的系统建设。关键是解决了大量的计算问题,建立了区域性通用模式。     

Multi-variable grey model (MGM (1,n,q)) based on genetic algorithm and its application in urban water consumption

Urban water consumption has some characteristics of grey because it is influenced by economy, population, standard of living and so on. The multi-variable grey model （MGM（1,n））, as the expansion and complement of GM（1,1） model, reveals the relationship between restriction and stimulation among variables, and the genetic algorithm has the whole optimal and parallel characteristics. In this paper, the parameter q of MGM（1,n） model was optimized, and a multi-variable grey model （MGM（1 ,n,q）） was built by using the genetic algorithm. The model was validated by examining the urban water consumption from 1990 to 2003 in Dalian City. The result indicated that the multi-variable grey model （MGM（1,n,q）） based on genetic algorithm was better than MGM（1,n） model, and the MGM（1,n） model was better than MGM（1,1） model.     

Molecular detection of virulence genes in Campylobacter species isolated from livestock production systems in South Africa

Campylobacter species are a major cause of foodborne bacterial infections in both developed and developing countries worldwide. Campylobacter jejuni is responsible for the majority of infections. This study was conducted to identify virulenceassociated genes in Campylobacter species isolated from livestock production systems in South Africa. A total of 250 fecal samples consisting of cattle(n=50), chickens(n=50), goats(n=50), sheep(n=50) and pigs(n=50) were randomly collected from livestock in Eastern Cape and KwaZulu-Natal provinces of South Africa between April and October 2018. The samples were analyzed for the presence of virulence genes in Campylobacter species using molecular PCR-based methods. It was found that 77 and 23% of Campylobacter jejuni and Campylobacter coli respectively were isolated from all the livestock samples. There were positive significant(P0.05) correlations amongst all the virulence genes that were investigated. Chisquare and Fisher's exact tests were implemented to test for the effect of livestock species on the presence or absence of virulence genes. The study demonstrated that most of livestock species can potentially cause zoonotic infections and food poisoning due to the high prevalence of Campylobacter. The high prevalence of virulence genes highlights the significance of Campylobacter in livestock production systems in South Africa. This requires the implementation of one-health approaches to reduce the impact of foodborne and zoonotic diseases for the welfare of human and animal health.     

红苕饲粮中添加铜和/或喹乙醇对猪生产性能及某些血液生化指标的影响

选体重约38公斤的长白(♂)×成华(♀)杂交猪20头,随机分为四组,饲予四种不同的饲粮,研究饲粮中添加铜和/或喹乙醇对猪生产性能和某些血液生化指标的影响。结果表明:基础组、加铜组、加喹乙醇组和两者同时加组全期日增重分别为674、761、796、678克,日采食量分别为2.50、2.65、2.74、2.40公斤,饲料利用率分别为3.73、3.49,3.44、3.54,添加铜和/或喹乙醇对试验第65天血清铜兰蛋白、尿素氨及屠宰率、背膘厚和眼肌面积无显著影响(p>0.05);添加铜使65天血清碱性碱酸酶活性极显著增高(p<0.01),添加喹乙醇有使之升高的趋势,两者同时添加时,碱性酸磷酶活性降低。     

不同施肥水平对木薯氮磷钾养分积累、分配及其产量的影响

 【目的】通过比较不同施肥水平下木薯氮磷钾养分积累、分配和产量的差异,探讨粤北坡岗地优质高产木薯氮磷钾养分的最佳用量。【方法】以木薯品种南美119为材料,采用“3414”方案,在粤北翁源进行大田试验。试验共设14个处理。【结果】施肥处理的氮素主要分配到地上部,不施肥处理的氮素则主要分配到根部;不同施肥处理的磷素均主要分配到地上部;不施肥处理和不施钾处理的钾素主要分配到根部,不施氮处理的钾素在根、冠间分配较均衡。在木薯不同生长阶段,植株氮磷钾含量均呈下降趋势,但施氮、磷、钾化学肥料处理植株氮磷钾含量的下降速度小于不施氮、磷、钾化学肥料的处理。处理N2P2K2的氮、磷、钾含量和积累量在各生育期均为最大,不施肥处理（N0P0K0）的氮、磷、钾含量和积累量在各生育期均为最小（P＜0.05）。产量最高的是N2P3K2处理,为22 694.06 kg·hm-2,其次是N2P2K2处理,为21 417.87 kg·hm-2。【结论】木薯产量、氮磷钾养分积累及其在根冠间的分配,对施肥水平高度敏感, 适当比例的氮磷钾肥配合施用既可以显著增加木薯植株的氮磷钾含量和积累量,又可以提高产量。在粤北坡岗地木薯生产中,氮素最重要,在氮素得到满足的条件下,磷素较钾素更重要。在本试验条件下,氮磷钾养分最佳用量为358.80 kgN·hm-2、89.10 kg P2O5·hm-2和187.50 kg K2O·hm-2。     

Current progress on genetic interactions of rice with rice blast and sheath blight fungi

Analysis of genetic interactions between rice and its pathogenic fungi Magnaporthe oryzae and Rhizoctonia solani should lead to a better understanding of molecular mechanisms of host resistance, and the improvement of strategies to manage rice blast and sheath blight diseases. Currently, dozens of rice resistance (R) genes against specific races of the blast fungus have been described. Among them, ten were molecularly characterized and some were widely used for breeding for genetic resistance. The Pi-ta gene was one of the best characterized rice R genes. Following the elucidation of its molecular structure, interaction, distribution, and evolution, user friendly DNA markers were developed from portions of the cloned genes to facilitate the incorporations of the Pi-ta mediated resistance into improved rice varieties using marker assisted selection (MAS). However, rice blast is still a major threat for stable rice production because of race change mutations occurring in rice fields, which often overcome added resistance based on single R genes, and these virulent races of M. oryzae pose a continued challenge for blast control. For sheath blight, progress has been made on the exploration of novel sources of resistance from wild rice relatives and indica rice cultivars. A major quantitative trait locus (QTL), named qSB9-2, was recently verified in several mapping populations with different phenotyping methods, including greenhouse methods. The ability to identify qSB9-2 using greenhouse methods should accelerate the efforts on the qSB9-2 fine mapping and positional cloning.     

Virus Location and Lymphocyte Apoptosis in Lymph Nodes of Piglets Infected with PCV-2

The present study has been performed to understand the location of the virus, type of apoptotic cells, and their relation to lymph nodes of piglets infected with porcine circovirus type Ⅱ （PCV-2）. Nine 32-day-old conventional piglets free of infection with PCV-2 were used, and distributed into three groups： control group （n = 3）, piglets inoculated with PCV-2 alone （PCV-2, n = 3）, and PCV-2 inoculated and KLH immunostimulated group （PCV-2 ＋ KLH, n = 3）. Superficial inguinal lymph nodes from all piglets were collected for histological examination after 32 days postinoculation, and immunohistochemistry for PCV-2 detection. Location of apoptotic cells was detected with TdT-mediated dUTP nick end labeling （TUNEL） and cell cycle, and the apoptotic rates were measured by flow cytometry. The characteristic histopathological lesions of the piglets in PCV-2 and PCV-2 ＋ KLH were lymphocyte depletions in the cortex and paracortex of the lymph nodes, epithelioid-like macrophage infiltration, and intracytoplasmic inclusion bodies presented in epithelioid-like macrophages. PCV-2 was mainly found in epithelioid-like macrophages by immunohistochemistry. In the lymph nodes, lymphocytes presented higher apoptotic rates in the cortex by TUNEL, special B-cell areas, and similar apoptotic cells were found in this compartment in the control. The apoptotic rates of the lymph nodes were 0.41, 3.34, and 4.88% in the control, PCV-2, and PCV-2 ＋ KLH groups by flow cytometry, respectively. The apoptotic rates of lymph nodes for PCV-2 and PCV-2 ＋ KLH piglets were significantly higher than those for the control group （P〈0.05 and P〈0.01）. The proliferation index （PI） was 0.17_＋0.01, 0.12_＋0.01 and 0.12_＋0.04 in the control, PCV-2, and PCV-2 ＋ KLH group, the PI of the control group was higher than that of the other groups, but without the statistical difference. PCV-2 can induce lymphocyte depletion in lymph nodes of piglets by blocking cell proliferation and promoting apoptosis. This is one o     

内脐蠕孢属、平脐蠕孢属和凸脐蠕孢属的研究

本文报道了平脐蠕孢属(Bipolaris)一个新种,一个新组合,5个新记录以及凸脐蠕孢属(Exserohilum)一个新记录。讨论了内脐蠕孢属(Drechslera)、平脐蠕孢属、凸脐蠕孢属与长蠕孢属(Helminthosporium)的关系,并就我国已报道的长蠕孢属真菌按Alcorn等~([1,3,4,5,24])人的意见,逐个进行了订正。