应用抑制性差减杂交技术克隆小鼠胸腺细胞发育相关新基因

目的:克隆胸腺细胞发育相关新基因.方法:应用抑制性差减杂交技术(suppression subtractive hybridization, SSH),构建了胸腺基质细胞系cDNA差减杂交文库,结合RACE及RT-PCR进一步克隆并验证新基因的cDNA全长序列.结果:筛选两个不同胸腺基质细胞系的差异表达基因,获得了差异表达的cDNA片段,克隆后挑选阳性克隆进行测序,成功克隆8个新基因片段.对其中两个新基因克隆C55和C91进行Northern杂交分析,mRNA转录体长度分别为1.4 kb及1.5 kb,C55的表达在两种胸腺基质细胞系中存在显著差异.进一步克隆了C55和C91两个新基因的cDNA全长序列,已被GenBank所接受.结论:抑制性差减杂交技术是克隆新基因片段的有效方法;成功克隆8个新基因片段及两个新基因的cDNA全长序列.     

应用抑制性差减杂交技术克隆小鼠胸腺细胞发育相关新基因

目的：克隆胸腺细胞发育相关新基因。方法：应用抑制性差减杂效技术（ｓｕｐｐｒｅｓｓｉｏｎ ｓｕｂｔｒａｃｔｉｖｅ ｈｙｂｒｉｄｉｚａｔｉｏｎ,ＳＳＨ）构建了胸腺基质细胞系ｃＤＮＡ关减杂效库,结合ＲＡＣＥ及ＲＴ－ＰＣＲ进一步克隆并验证新基因的ｃＤＮＡ全长序列。结果：筛选两个不同胸腺基质细胞系的差异表达基因,获得了差异表达的ｃＤＮＡ片段,克隆后挑选阳性克隆进行测序,成功克隆８个新基因片段。对其中两个新     

高脂血症敏感兔肝组织差减cDNA文库的构建

目的：构建高脂血症敏感兔肝组织表达基因的抑制差减cDNA文库。方法：分别从兔高脂血症敏感组和非敏感组肝组织分离mRNA，合成双链cDNA，酶切后将敏感组cDNA分成两组，分别与不同的接头连接，再通过再轮差杂交和两次抑制PCR得到两者之间差异表达的cDNA，将PCR产物与T／A载体连接构建差减cDNA文库，挑取克隆进行PCR扩增鉴定，结果：建的差减cDNA文库包含500个克隆，其中463个有插入片段，大小范围在250－700bp之间。结论：用抑制性差减杂交及T／A克隆技术成功构建了高脂血症敏感免疫差异表达基因差减cDNA文库。     

大鼠神经元Arnt2基因cDNA序列的分析

目的 克隆并分析神经元凋亡差异表达5号EST全长cDNA。方法 以大鼠大脑Marathon Ready cDNA为模板，采用SMART RACE技术克隆神经元凋亡差异表达5号EST全长cDNA，产物亚克隆刘pGEM-T easy质粒载体后进行序列测定以及同源性分析。结果 经过3次5’RACE扩增，得到的5号EST cDNA长度为5663bp，其中包含1个2136bp的完整的开放读码框序列，与已知大鼠基因芳香烃受体核转位因子2（Aryl hydrocarbon receptor nuclear translocator2，Arnt2）完全同源：该cDNA 3’瑞非编码区长达3323bp，包含3个AATAAA加尾信号和1个由12个腺嘌呤核苷酸组成的polyA序列。结论 5号EST目标基因为大鼠基因Arnt2，该基因3’端完整的非编码区cDNA序列为首次报道。神经元凋亡差异表达基因Arnt2的克隆鉴定为深入研究小脑颗粒神经元低钾性凋亡机制奠定了基础。     

抑制性消减杂交法构建甲状腺癌差异表达基因文库

目的：筛选并克隆在甲状腺癌组织与正常甲状腺组织之间差异表达的基因。方法：(1)应用抑制性消减杂交(SSH)进行基因差示表达分析,构建人甲状腺癌组织与正常甲状腺组织之间差异表达的cDNA消减文库;(2)克隆、鉴定甲状腺癌组织特异性高／低表达的基因;(3)登录Genbank,运用Blastn程序进行同源性分析。结果：成功构建了高消减效率的人甲状腺癌cDNA消减文库,对其中数个克隆的插入cDNA片段进行测序,经检索Genbank表明,正向SSH产物中有3个片段与来源于结肠上皮腺癌和Lung Epidermoid carcinoma的EST有100％同源性,提示它们来自恶性肿瘤相关基因。反向SSH产物中有5个片段为未知新序列,提示它们可能来自于在甲状腺癌中特异性低表达的新基因。结论：通过抑制性消减杂交技术,构建了人甲状腺癌cDNA消减文库,为下一步筛选鉴定甲状腺癌特异性基因及其全长克隆、功能研究等工作打下了基础。     

淡色库蚊抗药性相关基因--NYD-MLC2基因的克隆与分析

目的:获取淡色库蚊抗药性相关基因NYD-MLC2的cDNA全长序列并鉴定其在抗性品系和敏感品系中的表达差异。方法:根据抑制性差减杂交(SSH)结合cDNA芯片分离获得的淡色库蚊抗药性相关NYD-MLC2基因片段序列设计引物,采用快速扩增cDNA末端法(rapidamplificationofcDNAends,RACE)扩增NYD-MLC2基因3′、5′端,经对位拼接获得全长序列,并进行生物信息学分析;荧光定量PCR验证此基因在抗性和敏感品系的表达差异。结果:获得淡色库蚊NYD-MLC2cDNA全长序列,开放阅读框为630bp(GenBank/NCBIDQ140391),编码210个氨基酸。蛋白质序列分析显示,NYD-MLC2与冈比亚按蚊(Anophelesgambiae)一个未知功能的蛋白同源性最高,为91%;实时荧光定量PCR结果显示,NYD-MLC2在淡色库蚊溴氰菊酯抗性品系中的表达量是敏感品系的4.08倍。结论:获得淡色库蚊抗药性相关NYD-MLC2基因cDNA全长序列,并证实其在淡色库蚊溴氰菊酯抗性品系中高表达,提示NYD-MLC2与淡色库蚊溴氰菊酯抗药性相关,值得进一步研究。     

应用抑制性差减杂交技术构建铁皮石斛差减cDNA文库的探讨

【目的】探讨构建铁皮石斛抑制差减文库的方法,为克隆石斛碱生物合成相关功能基因奠定基础。【方法】采用抑制性差减杂交(SSH)技术,分别以4年生和1年生铁皮石斛叶片互补脱氧核糖核酸(cDNA)作为检测子(tester)与驱赶子(driver),将所获得差减cDNA片段克隆入质粒表达载体(Point^TMXa-1 T-Vector),转化大肠杆菌JM109,聚合酶链反应(PCR)扩增鉴定插入片段。【结果】成功地构建了与石斛碱生物合成相关的差减cDNA文库,获得的正、反向差减文库分别含560、220个重组子;插入片段的平均大小为550bp。【结论】所构建的差减cDNA文库适合进一步克隆分析石斛碱相关功能基因研究。     

淡色库蚊抗性相关基因--NYD-GBE基因的克隆与分析

目的:获取淡色库蚊抗药性相关NYD-GBE基因cDNA全长序列并验证其在抗性品系和敏感品系中的表达差异。方法:根据抑制性差减杂交(SSH)结合cDNA芯片分离获得的淡色库蚊抗性相关NYD-GBE基因片段设计引物,采用快速扩增cDNA末端法(rapidamplificationofcDNAends,RACE)扩增糖原分支酶基因5′、3′端,经对位拼接获得全长序列,并用相应的软件进行生物信息学分析。结果:获得淡色库蚊NYD-GBEcDNA全长序列,开放阅读框为2070bp(GeneBank/NCBIDQ102393),编码689个氨基酸。蛋白质序列分析显示,NYD-GBE与冈比亚按蚊(Anophelesgambiae)和拟暗果蝇(Drosophilapseudoobscura)一个未知功能的蛋白同源性最高,为82%和72%,与人糖原分支酶的基因同源性次之为60%。荧光定量PCR结果显示,NYD-GBE在淡色库蚊溴氰菊酯抗性品系中的表达量是敏感品系的19.7倍。结论:获得淡色库蚊抗药性相关NYD-GBE基因全长cDNA序列,并证实其在淡色库蚊溴氰菊酯抗性品系中高表达,提示NYD-GBE与淡色库蚊溴氰菊酯抗性相关,值得进一步研究。     

肾癌差异表达基因克隆的研究

目的 克隆并鉴定肾癌与正常肾之间差异表达的基因。方法 应用抑制性消减杂交技术构建人肾癌组织与正常肾组织差异表达的cDNA消减文库,并从中克隆鉴定出肾癌差异表达的基因。结果 构建成功了高消减效率的人肾癌cDNA消减文库,对其中5个克隆插入的cDNA片段进行测序后经Genbank检索表明,5个片段均为未知新序列,其中GYIZ-RCC18为3个拷贝,提示以上5个cDNA征段可能来自3个新基因。Northern杂交分析显示,GYIZ-RCC18在肾癌组织中有明显表达,而在正常肾组织中无表达,这证明GYIZ-RCC18是肾癌相关的新基因。结论 人肾癌cDNA消减文库的建立为进一步筛选,克隆肾癌特异性表达的新基因奠定了基础。     

家族性急性髓系白血病相关新基因ELF2C cDNA全长的克隆

目的克隆家族性急性髓系白血病相关新基因全长,在分子水平上探讨急性白血病发生发展的机制。方法以构建的家族性急性髓系白血病抑制性？肖减性文库中1个有差异表达的新基因EST序列（zywb4）为基础,综合应用电子克隆和cDNA末端快速扩增法（RACE）技术克隆家族性急性髓系白血病相关新基因的全长cDNA。结果获得家族性急性髓系白血病差异表达新基因ELF2C的全长cDNA和432bp的开放阅读框（ORF）,Blast检索为一功能未知基因,被GenBank收录,注册号为DQ359746。结论成功获得一个家族性急性髓系白血病相关新基因ELF2CcDNA全长,为进一步研究其功能提供了依据。     

Suppression subtractive hybridization for identifying differentially expressed genes in renal cell carcinoma

Objective To construct a renal cell carcinoma (RCC) cDNA subtractive library using suppres sion subtractive hybridization.Methods Polyadenylated RNA ［Poly (A)(+) RNA］ was isolated from tissues of RCC and norm al kidney, and single- strand cDNAs and double-strand cDNAs were synthesized in turn. RCC cDNAs were divided into two groups and ligated to the specific adaptors l and 2, and then h ybridized with normal kidney cDNA twice with two rounds of suppression PCR. Sec ond round PCR products were cloned to T/A plasmid vectors to set up the subtract ive library. One hundred clones were randomly picked to perform enzyme digest a nalysis, and some underwent sequence analysis and Northern blot to identify RCC specifically expressed genes. SMART RACE procedure was operated to clone full l ength novel RCC specifically expressed genes.Results A human RCC subtractive library with high subtractive efficiency was successfull y set up. The amplified library contains 350 positive clones. Random analysis of 100 clones with enzyme restriction showed that 85 plasmids in the clones cont ained 50-400 bp inserts. Sequence analysis was performed for 10 clones. All t he 10 sequences were unknown before and derived from 6 unique, novel genes among which the cDNA insert RCC18 had five copies. Northern blot analysis showed tha t RCC18 cDNA was highly expressed in RCC, but no signal could be detected in nor mal kidney. Using SMART RACE technique, we obtained the full length of the nove l gene RCC18.Conclusions The constructed cDNA subtractive library of human RCC is a highly efficient one and lays a solid foundation for large scale screening and cloning new and speci fic oncogenes or tumor suppressor genes of RCC. The novel specifically expresse d genes provided an important clue for studying the mechanisms of occurrence and development of RCC.     

应用抑制消减杂交技术克隆人大肠癌转移相关新基因

目的 克隆新的大肠癌转移相关基因，为进一步阐述大肠癌转移的分子机制提供线索。方法 利用抑制消减杂交技术，以1对来自同一亲本、转移能力不同的大肠癌细胞株SW620和SW480为研究对象．构建2种大肠癌转移促进基因和转移抑制基因的cDNA消减库。随机挑取库克隆进行差异筛选．对所得的差异片段进行测序和同源性分析，利用Northern Blot对新基因的表达情况进行验证。结果 两种消减库分别含有235和232个白色克隆．90％以上的白色克隆含有插入片段。随机挑取约200个阳性克隆进行差异筛选．共获得29个差异片段。测序及同源分析发现15个为未知基因，GenBank登陆号为CD485499-CD485513。其中与5号染色体序列同源的基因有6个。结论 抑制消减杂交技术是筛选、克隆大肠癌转移相关新基因的有效手段：5号染色体上可能存在多个与大肠癌转移相关的新基因位点：筛选到的新基因片段为进一步克隆基全长、研究基因功能提供了实验基础。     

应用抑制消减杂交技术克隆人大肠癌转移相关新基因

目的 克隆新的大肠癌转移相关基因,为进一步阐述大肠癌转移的分子机制提供线索。方法 利用抑制消减杂交技术,以1对来自同一亲本、转移能力不同的大肠癌细胞株SW620和SW480为研究对象,构建2种大肠癌转移促进基因和转移抑制基因的cDNA消减文库。随机挑取文库克隆进行差异筛选,对所得的差异片段进行测序和同源性分析,利用Northern Blot对新基因的表达情况进行验证。结果 两种消减文库分别含有235和232个白色克隆,90%以上的白色克隆含有插入片段。随机挑取约200个阳性克隆进行差异筛选。共获得29个差异片段。测序及同源分析发现15个为未知基因,GenBank登陆号为CD485499-CD485513。其中与5号染色体序列同源的基因有6个。结论 抑制消减杂交技术是筛选、克隆大肠癌转移相关新基因的有效手段;5号染色体上可能存在多个与大肠癌转移相关的新基因位点;筛选到的新基因片段为进一步克隆其全长、研究基因功能提供了实验基础。     

大鼠肝再生中1个表达上调新基因的克隆表达及分析

目的　克隆肝再生相关新基因。方法　以抑制性消减杂交得到的1个EST为模板制备探针,运用Southern印迹方法,从构建的再生肝76 h c DNA文库中调取了它的c DNA全长,并利用基因原核表达技术,表达并纯化出它的蛋白产物,制作了该蛋白的兔源多抗,分别用所制该基因的探针,采用点杂交技术检测了0～76 h的再生肝材料。结果　获得了1个新基因全长,BL AST检索结果为1未知功能基因,暂时命名为liver regeneration relatedprotein(L RRP) ,大鼠基因组数据库中检索结果证实L RRP位于19q12且由4个外显子和3个内含子组成,递交Gen Bank获登录号为AY0 98917。表达纯化出了它的融合蛋白产物,并得到了它的多克隆抗体。点杂交结果也证实了基因在肝切除后76 h明显上调。结论　L RRP基因全长的克隆和它的高效多克隆抗体的获得为进一步研究该基因的功能奠定了基础。     

Cloning the full-length cDNA of a gene responsible for vascular smooth muscle cell proliferation in atherogenesis and study of function

Objective To clone the full-length cDNA of a gene responsible for vascular smooth muscle cell(v-SMC)proliferation in atherogenesis,and study its function.Methods Oxidized low density lipoprotein(ox-LDL)at optimal concentration was used as the stimulant to induce v-SMC proliferation in culture medium.A cDNA subtractive library of v-SMC proliferation specific to ox-LDL stimulation was established using subtractive hybridization technique.Methods,including blotting,Northern hybridization and gene sequencing,were used to clone new gene fragments.By using full-length cDNA screening and protein expression techniques,one full-length cDNA was cloned and its function was studied.Results One full-length cDNA was cloned.The new gene(Genbank AF 174647) expressed a 44 kDa protein,which mijht be associated with the activity of ox-LDL.Conclusion The new gene cloned may be associated with SMC proliferation in atherogenesis.     

应用抑制性消减杂交技术从斑秃脱发区毛乳头中克隆出一条自身抗原基因

目的　寻找斑秃脱发区毛乳头中特异表达的基因片段 ,探讨斑秃发病机制。方法　应用抑制性消减杂交构建斑秃脱发区毛乳头差异表达基因的cDNA文库 ,并通过PCR筛选、杂交验证和同源性检索对差异表达基因进行分析。结果　成功建立了高消减效率的斑秃脱发区毛乳头cDNA消减文库 ,并克隆到一条斑秃毛乳头特异表达的基因片段DP3( 3 0 7bp) ,应用cDNA斑点杂交及Northern杂交证实它仅在脱发区毛乳头特异表达 ,同源性检索其为一条甲状腺相关的自身抗原基因。结论　DP3在斑秃脱发区毛乳头的特异表达提示其可能参与斑秃的发病过程 ,它的克隆为斑秃发病机制的自身免疫学说进一步提供了实验依据     

cDNA microarray in isolation of novel differentially expressed genes related to human glioma and clone of a novel full-length gene

Background This investigation was undertaken to obtain differentially expressed genes related to human glioma using cDNA microarray and the characterization of one novel full-length gene. Methods Total RNA was extracted from human glioma tissues and normal brain tissues, and mRNA was used to make probes. After hybridization and washing, the results were scanned using a computer system. The gene named 681F05 clone was an expressed gene to human glioma through four-time hybridization and scanning. Subsequently northern blot analysis was performed by northern blot, 5‘RACE and bioinformatics. Results Fifteen differentially expressed genes to human glioma were obtained through four-time hybridization and scanning. Northern blot analysis confirmed that 681F05 clone was low-expressed in human brain tissues and over-expressed in human glioma tissues. The analysis of BLASTn and BLASTx showed that 681F05 clone is two cDNA clones encoding two novel proteins that are highly identified to the cyclophilin isoform 10 of C. Elgans, respectively. Sequence analysis revealed the two cDNA clones are two different splicing variants of a novel cycophilin-like gene (PPIL3a and PPIL3b). Conclusions cDNA microarray technology can be successfully used to identify differentially expressed genes. The novel full-length gene of human PPIL3 may be correlated with the formation of human glioma.