GST/MKRN1融合蛋白的表达、纯化及多克隆抗体制备

目的:利用大肠杆菌BL21(DE3)表达GST/MKRN1融合蛋白,亲和层析分离纯化目的蛋白,进行动物免疫制备多克隆抗体。方法:MKRN1cDNA全长1449bp,编码482个氨基酸残基。将其基因片段克隆到pGEX-4T-1载体上,获得pGEX-4T-1-MKRN1原核表达重组质粒,转化大肠杆菌BL21(DE3),经IPTG诱导表达,在大肠杆菌表达系统中获得可溶性表达,经谷胱甘肽Sepharose4B介质填充的层析柱分离纯化蛋白,制备抗原免疫动物,得到pGEX-4T-1-MKRN1多克隆抗体。结果:ELISA结果显示血清抗体效价可达到1∶256000。通过Western免疫印迹及免疫细胞荧光分析,自制的多克隆抗体能特异地与MKRN1蛋白相互作用,可用于免疫细胞化学分析。结论:制备了效价和特异性良好的抗MKRN1多克隆抗体,经实验验证获得的免疫血清能够满足针对MKRN1的Western免疫印迹和细胞免疫组化检测的实验要求,为今后深入研究MKRN1表达的组织分布、细胞内定位及与端粒酶催化亚基(hTERT)之间相互作用的生物学意义提供了有用的实验工具。     

H9N2型禽流感病毒核蛋白的原核表达及多克隆抗体制备

目的:利用大肠杆菌表达H9N2禽流感病毒(AIV)核蛋白(NP)与GST的融合蛋白并分离纯化,进行动物免疫制备多克隆抗体。方法:根据AIV NP基因序列设计引物,将已经获得的NP基因定向克隆到GST融合原核表达载体pGEX-KG并转化大肠杆菌,在IPTG诱导下获得高效表达。经谷胱甘肽层析柱分离纯化蛋白,制备抗原免疫家兔,得到pGEX-KG-NP多克隆抗体。结果:SDS-PAGE分析显示融合表达蛋白GST-NP相对分子质量约82 000,表达量约占菌体总蛋白的20%。Western-blot和ELISA检测结果表明,重组NP能与鸡抗AIV抗体发生明显的抗原抗体反应。自制的多克隆抗体能特异地与NP相互作用,可用于AIV病原诊断。结论:获得了NP基因的高效表达产物;制备了效价和特异性良好的抗重组NP多克隆抗体。经实验验证表达产物具有活性,多克隆抗体效价高,特异性强,为AIV病原诊断试剂的研发奠定了基础。     

酸弗林蛋白酶酸性氨基酸簇分选蛋白-1的原核表达、纯化及多克隆抗体制备

目的：原核表达和纯化PACS-1,并制备其多克隆抗体。方法：通过RT-PCR扩增出PACS-1的编码基因,测序正确后克隆入原核表达载体pGEX4T-1,转化大肠杆菌BL21（DE3）,以IPTG诱导PACS-1与GST融合蛋白的表达并经Glutathione Sepharose 4B纯化;经SDS-PAGE和Western blot鉴定,应用纯化的蛋白免疫家兔制备多克隆抗体,用ELISA测定抗体的效价。结果：表达和纯化了PACS-1,并获得了较高效价的抗血清。结论：获得纯化的PACS-1及其多克隆抗体,为进一步研究PACS-1的功能奠定了基础。     

自噬相关基因Atg5的原核表达及多克隆抗体制备

目的：克隆自噬相关基因Atg5,在大肠杆菌中重组表达后制备抗Atg5多克隆抗体。方法：用RT-PCR方法从RAW264．7细胞基因组中克隆Atg5基因,连接至pQE80L原核表达载体后转化大肠杆菌DH50α进行诱导表达,SDS-PAGE及Westernblot鉴定表达蛋白;目的蛋白纯化后,以100μg／kg纯化的蛋白免疫新西兰兔,制备抗Atg5多克隆抗体;提取RAW264．7细胞总蛋白,以制备的抗Atg5多抗进行Westernblot反应,检测多抗的生物学活性。结果：克隆了Atg5基因,在大肠杆菌中表达了重组Atg5,SDS-PAGE分析显示表达产物相对分子质量与预期值一致,Western blot结果证明该产物具有较高的生物学活性,纯化蛋白免疫动物后制备了抗Atg5多克隆抗体。结论：在大肠杆菌中表达了重组Atg5,制备了抗Atg5多克隆抗体,为自噬的检测和研究提供了工具。     

人DFF45蛋白多克隆抗体制备及其初步应用

目的：表达、纯化带GST标签的DNA裂解因子45（DNA fragmentation factor 45 ,DFF45）融合蛋白并制备多克隆抗体。方法：构建pGEX-5X-1/DFF45原核表达质粒,转化大肠杆菌BL21,用IPTG诱导融合蛋白表达,经纯化后免疫日本大耳白兔得到多克隆抗体并用CNBr-activated Sepharose? 4B进行纯化。用间接ELISA法检测抗体效价,Western blot鉴定抗体特异性,同时用免疫荧光染色鉴定抗体特异性并观察DFF45的细胞定位。进一步检测DFF45在人类几种细胞系的表达差异情况。结果：成功构建原核表达质粒,表达、纯化DFF45蛋白并免疫动物后得到多克隆抗体。间接ELISA法显示抗体效价达1:20 000,Western blot确定抗体具有高度特异性。应用该抗体检测发现DFF45在人类几种细胞系中表达存在差异并观察到其细胞定位。结论：DFF45多克隆抗体的成功制备及其在人类细胞系的差异表达,为进一步研究DFF45基因与肿瘤及其相关疾病的关系奠定了基础。     

人类博卡病毒(HBoV)非结构蛋白NS1基因的克隆、原核表达及多克隆抗体的制备

目的:克隆、表达、纯化人类博卡病毒(HBoV)非结构蛋白NS1,制备抗NS1多克隆抗体。方法:利用PCR扩增HBoV非结构蛋白NS1基因,将其克隆至pMAL-c2X表达载体上,重组质粒转化大肠杆菌DH10B,IPTG诱导表达。表达的融合蛋白经Amylose Resin亲和层析柱纯化后,免疫新西兰大白兔制备多克隆抗体。用间接ELISA法检测抗体效价。结果:原核表达融合蛋白MBP-NS1,并获得了其多克隆抗体,抗体效价达到1∶32000。结论:在原核表达系统中表达、纯化了融合蛋白,制备抗NS1多克隆抗体,为进一步研究该病毒非结构蛋白基因的转录和翻译机制提供可靠的工具。     

人接头蛋白NRBP的表达、纯化及多克隆抗体制备

目的:制备接头蛋白NRBP的兔多克隆抗体,并检测该抗体的效价及特异性。方法:PCR方法以重组质粒PEF-NRBP为模板,获得NRBP全长及NRBP(1-99Aa)cDNA,构建到原核表达质粒pET-21a及pGEX-6P-1中。分别转入大肠杆菌BL21菌株,IPTG诱导表达后,纯化并鉴定表达产物将其免疫家兔,间接ELISA法及免疫印迹等方法鉴定抗体。结果:成功获得人NRBP的cDNA,构建得到相关的原核表达质粒,在大肠杆菌中可诱导性高表达,纯化后蛋白免疫家兔制备得到的抗血清经ELISA检测为阳性结果,4只免疫家兔的抗体效价约为1:5 200～1:40 000。Western印迹结果显示,该抗体可特异性的识别真核细胞外源性及内源性约60kDa的NRBP蛋白,并且具有较强免疫沉淀能力。结论:NRBP多克隆抗体具有很好的特异性和敏感性,该抗体的成功制备为进一步研究NRBP的功能提供了重要工具。     

大鼠RVLG cDNA的克隆、原核表达和小鼠抗RVLG蛋白多克隆抗体的制备

为了识别大鼠卵巢中的生殖细胞,在原核系统中表达和纯化RVLG蛋白并制备了多克隆抗体.采用RT-PCR方法从大鼠睾丸组织中扩增获得RVLG cDNA片段,然后克隆到pMD19-T载体上进行测序,经双酶切回收目的基因片段后,将其插入到原核表达载体pGEX-4T-1上,转入大肠杆菌BL21(DE3)中诱导表达.纯化后的GST-RVLG融合蛋白免疫昆明(KM)小鼠,最后给小鼠腹腔注射S180细胞制备抗RVLG腹水多克隆抗体.用Western blotting及免疫组织化学法鉴定RVLG腹水多克隆抗体的特异性,间接ELISA法测定该抗体的效价.序列分析表明,所克隆的RVLG cDNA片段比GenBank中报道的大鼠RVLG cDNA(NM_001077647)多60 bp,原因是由于RVLG的可变剪切方式造成的.本研究成功构建了重组表达质粒pGEX-RVLG,且GST-RVLG融合蛋白在大肠杆菌BL21(DE3)中高效表达,表达的目的蛋白占菌体总蛋白的10%以上.制备的抗体可特异性识别RVLG蛋白,其效价达1:20 000.获得的高效价、高特异性的小鼠抗RVLG蛋白腹水多克隆抗体为下阶段研究RVLG的特异性表达奠定了基础.     

沙门菌外膜蛋白D的原核表达及多克隆抗体制备

目的:在大肠杆菌中表达沙门菌外膜蛋白(OMP)D,纯化后制备兔抗OMPD抗体。方法:用PCR方法从鼠伤寒沙门菌中扩增出ompD基因,并插入融合表达载体pET-28a(+)的多克隆位点,构建重组表达质粒pET28a(+)-ompD;以重组质粒转化大肠杆菌BL21(DE3),筛选阳性重组菌株,经IPTG诱导目的蛋白表达,在变性条件下对目的蛋白进行亲和层析纯化;以表达的OMPD蛋白免疫家兔,制备抗OMPD的多克隆抗体并进行鉴定。结果:扩增了ompD基因,测序证实正确后亚克隆于表达载体pET-28a(+)中,经PCR筛选和酶切鉴定获得阳性克隆,经诱导在大肠杆菌中表达出相对分子质量为40×103的目的蛋白并进行纯化;纯化的OMPD免疫家兔后,能有效地刺激特异性抗体的产生,抗血清的效价达到1∶10000以上,且具有良好的特异性。结论:构建ompD基因的原核表达载体,并在大肠杆菌中获得高效表达;制备出兔抗OMPD抗体,效价及特异性均良好,为进一步制备肠黏膜高亲和力疫苗奠定了基础。     

拟南芥甘露糖苷酶Ⅰ和人 N-乙酰葡萄糖胺转移酶Ⅰ的原核表达及其多克隆抗体制备

目的：在大肠杆菌中分别重组表达拟南芥甘露糖苷酶Ⅰ（ATMDSI）和人N-乙酰葡萄糖胺转移酶I（HsGnTI）,制备其多克隆抗体,为基因表达鉴定提供检测抗体。方法：用PCR方法克隆ATMDSI、HsGnTI基因片段,连接至pBV220表达载体后转化大肠杆菌DH5α,获得表达菌株,通过42℃升温诱导表达,制备纯化ATMDSI和HsGnTI;纯化的蛋白以80μs／ks的剂量免疫大耳白兔,经3次免疫后,采集血清制各其相应的多克隆抗体;采用Western印迹检测多克隆抗体的特异性。结果：获得ATMDSI和HsGnTI基因片段,并构建了其相应的原核表达载体pBV220-ATMDSI、pBV220-HsGnTI,在大肠杆菌中表达了重组ATMDSI和HsGnTI,SDS-PAGE分析显示其相对分子质量分别为45．3×10^3和46．9×10^3,与理论值一致;用纯化的蛋白免疫大耳白兔后制备了抗ATMDSI、HsGnTI多克隆抗体,Western印迹结果证明该抗体具有较高的特异性。结论：获得了特异性较高的抗ATMDSI、HsGnTI多克隆抗体血清,为甘露糖苷酶Ⅰ和N-乙酰葡萄糖胺转移酶Ⅰ的研究提供了检测抗体。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.