3号染色体短臂21-22区域63个新基因在鼻咽癌组织中的差异表达

目的寻找与鼻咽癌发病密切相关的未知基闪。方法对63个定位于3号染色体短臂21-22 D3S1609-D3S1295区域的单拷贝并代表未知基因的EST簇进行网上克隆，在获取基因大片段或全长cDNA序列的基础上，应用半定量逆转录．聚合酶链反应检测63个未知基因在4种鼻咽癌细胞铢、32例鼻咽部低分化鳞状细胞癌组织和16例鼻咽部慢性炎症组织中的表达状况。结果49个未知基因在鼻咽癌组织和鼻咽部慢性炎症组织问的表达水平无显著性差异；8个未知基因在鼻咽癌和鼻咽部慢性炎症组织中均不表达；2个未知基因在鼻咽癌组织中表达明显增强；4个未知基因在鼻咽癌组织中表达明显减弱，其中Hs．27566基因在鼻咽癌细胞和组织中均显著低表达或不表达。结论在染色体3p21-22D3S1609．D3S1295区域构建了63个未知基因在鼻咽癌的表达差异谱：筛选出6个在鼻咽癌组织中差异表达的未知基因。     

3号染色体短臂21-22区域63个新基因在鼻咽癌组织中的差异表达

目的 寻找与鼻咽癌发病密切相关的未知基因。方法 对63个定位于3号染色体短臂21-22D3S1609-D3S1295区域的单拷贝并代表未知基因的EST簇进行网上克隆,在获取基因大片段或全长cDNA序列的基础上,应用半定量逆转录-聚合酶链反应检测63个未知基因在4种鼻咽癌细胞株、32例鼻咽部低分化鳞状细胞癌组织和16例鼻咽部慢性炎症组织中的表达状况。结果 49个未知基因在鼻咽癌组织和鼻咽部慢性炎症组织间的表达水平无显著性差异;8个未知基因在鼻咽癌和鼻咽部慢性炎症组织中均不表达;2个未知基因在鼻咽癌组织中表达明显增强;4个未知基因在鼻咽癌组织中表达明显减弱,其中Hs.27566基因在鼻咽癌细胞和组织中均显著低表达或不表达。结论 在染色体3p21-22D3S1609-D3S1295区域构建了63个未知基因在鼻咽癌的表达差异谱;筛选出6个在鼻咽癌组织中差异表达的未知基因。     

Cloning and characterization of a novel gene encoding a putative seven-span transmembrane protein localized in endoplasmic reticulum

To clone and analyze the structure of a novel gene, named EST-1 (endoplasmic reticulum-localized seven-span transmembrane protein-1) and to analyze the expression pattern and intracellular location of EST-1. Methods:The cDNA library was screened to isolate novel cDNA fragment. The structure of novel gene was analysed by computer software. Expression of EST-1 was analyzed by dot blot and Northern blotting, Intracellular localization was observed after EST-1-enhanced green fluorescence protein (EGFP) fusion gene was transfected into mammalian cells. Results: The full-length cDNA of mouse EST-1 was 1 802 bp, with a 1 293 bp open reading frame encoding 431 amino acids. It was predicated that protein encoded by FST-1 contained a signal peptide sequence at the N-terminus, seven putative transmembrane domaius,and an ER-retaining signal at the C-terminus, EST-1-EGFP fusion protein showed an ER-like intracellular distribution in mammalian cells. Expression pattern analysis showed that EST-1 is expressed in all tissues examined. Conclusion: EST-1 is encoding a putative seven-span transmembrane protein localized in endoplasmic retieulum. EST-1 was expressed in all tissues examined, suggesting an essential function of EST-1 in cells.     

A novel serine protease SNC19 associated with human colorectal cancer

Objective To study the structure and function of a novel serine protease gene associated w ith human colorectal cancer SNC19.Methods The cDNA sequence was determined by both manual and automatic sequencing techniq ues. The full length cDNA sequence was obtained by the 5’-Rapid Amplification of cDNA Ends technique and web-based analysis. Open reading frame analysis and protein function prediction were also performed. Northern blot was used to det ect the expression of SNC19 in various human normal tissues and tumor cell lines . Fluorescent in situ hybridization combined with fluorescent R-banding techni que was employed to map the SNC19 gene on human chromosome.Results Full length SNC19 cDNA, size 3152 bp, encodes a protein highly homologous to a m ouse serine protease epithin. In normal human tissues, high SNC19 expression le vels were observed in the kidney, pancreas, prostate, small intestine and colon; moderate SNC19 expression levels were observed in the placenta, lung, liver, sp leen thymus, testis and peripheral blood lymphocytes; and extremely low expressi on levels were observed in the heart, brain, skeletal muscle and ovary. In tumo r cell lines, colorectal cancer cells SW480, SW620, SW1116 and Colo205, breast c ancer cell Bcap37 and gastric cancer cells MKN28 and SGC7901 showed high levels of SNC19 expression; cervical cancer cell HeLa-S3, lung cancer PAA, oral epithe lial cancer cell KB and lymphoma cell Raji showed moderate levels of SNC19 expre ssion; and tongue squamous cancer cell Tca8113, leukemia cells HL-60, K562, MOL T-4, lung cancer cell A549 and melanoma cell G361 showed very low levels of SNC 19 expression. SNC19 was mapped to human chromosome 11q24-25. Conclusion SNC19 encodes a novel human serine protease with 855 amino acid residues. As a novel serine protease associated with human colorectal cancer, the expression of SNC19 in various tissues and cell lines may have very important impact on their phenotypes and biological behaviors.     

日本血吸虫thioredoxin基因的克隆和表达

目的 结合分子生物学和生物信息学方法筛选鉴定日本血吸虫新基因。方法 从日本血吸虫(Schistosoma japonicum，大陆株)成虫cDNA库中获取表达序列标签(expressed sequence tag，EST)，用电子拼接的方法延伸序列，用NCBI提供的BLAETx程序和Genbank数据库进行同源性分析以筛选基因；设计特异性引物从日本血吸虫成虫mRNA中扩增筛选基因并预测和分析；扩增产物克隆到原核表达载体并表达。结果 筛选出日本血吸虫Thioredoxin全长基因并对其进行了序列分析，克隆全长cDNA至PET原核载体并表达成功。结论 结合EST、电子延伸和传统的分子生物学方法是高效筛选S.jiaponicum功能基因的有效策略。     

Identification and expression of a novel human testis-specific gene by digital differential display

Background Evidence for the importance of genetic factors in male infertility is accumulating. This study was designed to identify a novel testis-specific gene related to spermatogenesis by a new strategy of digital differential display (DDD).Methods Based on the generation of expressed sequenced tags (ESTs), comparing the testis libraries with other tissue or cell line libraries by the DDD program, we identified a new contig of the ESTs which were derived from testis libraries and represented a novel gene. Multi-tissue RT-PCR was performed to analyse its tissue-specific expression. The full-length cDNA of the new gene was obtained using the BLAST program. Sequencing was performed and the result was analysed. Semiquantitative RT-PCR and Northern blot analyseis of mRNA from differential normal tissues were performed to clarify the expression pattern of the new gene. The sequence of the opening reading frame was integrated into the pQE-30 vector expressed in Escherichia coil strain M15(pREP4). With IPTG induction, the target protein was detected.Results A full-length cDNA sequence of the new gene named SPATA12 (GeneBank accession number AY221117) in human testis was identified. SPATA12 was 2430 bp in length, located in chromosome 3p21.1-3p21.2. The sequence of the opening reading frame was 676 - 1248 bp, as was confirmed by RT-PCR and sequencing. The cDNA encodes a novel protein of 190 amino acids with a theoretical molecular weight of 20417. 8 and isoelectric point of 5. 23. The sequence has no significant homology with any known protein in databases. Semi-quantitative RT-PCR and Northem-blot analyses of multiple tissues showed that SPATA12 was expressed significantly in normal human testis. The expression recombinant of SPATA12 was constructed and a high level of the histidine-tagged fusion protein was obtained.Conclusions DDD can be confirmed by SPATA12 as a novel computational biology-based approach for identification of the testis-specific expression genes. SPATA12 may function as a testicular germ cell associated gene that plays some roles in spermatogenesis. Moreover, a great amount of SPATA12 protein could be obtained by the gene recombination technique, thus providing a reliable foundation for investigating the biological function of this new protein.     

一种新型单羧酸转运体基因的分离与克隆

目的 分离、克隆编码肾脏甲酸盐（formate)和（或）草酸盐（oxalate)转运体的cDNA,以研究Cl^-在近端肾小管转运的机制。方法 根据细菌Oxlt(formate-oxalate交换体）的基因序列在哺乳动物表达序列标签（express sequence tag,EST)数据库中查找与其相似的cDNA。按筛选到的cDNA设计探针,应用小鼠多组织杂交膜分析该基因的组织表达谱。结果 在小鼠肾cDNA文库中有一个与Oxlt极其相似的EST,序列分析显示了其有一编码429个氨基酸蛋白质的开放阅读框。从编码的顺序中可发现该序列与单羧酸转运家族（monocarboxylate transporter,MCT)极为相近,与小鼠MCT1的氨基酸一致性为30％,与小鼠MCT2为33％,与大鼠MCT329％。其中第14－158个氨基酸中有25％与OxlT相同。Northern印迹发现,新的基因在小鼠肾脏中表达最多,肝脏和心脏中极少表达。结论 该基因是一新型的MCT家族成员,主要在肾脏中表达,其功能可能是介导肾小管的formate转运。     

鼻咽癌易感/抑瘤基因的功能基因组学研究

鼻咽癌组织在染色体3p,9p,6q,11q,13 q和14q等区域存在较高的等位基因不平衡,表明这些区域存在与鼻咽癌相关的抑瘤基因.采用cDNA代表性差异分析等方法成功获得了候选的鼻咽癌易感/仰瘤基因,并进行了基因功能研究.发现:(1)Cx基因的表达增强是由于肿瘤细胞为突破细胞通讯功能的障碍,试图重建细胞间隙连接的一种表达变异;(2)BRD7基因是一个与细胞周期调控密切相关的核转录调控因子;(3)NAG7基因具有双重生物学功能--在抑制低侵袭能力的HNE1细胞增殖的同时,能够增加HNE1和6-10B细胞的侵袭潜能;(4)NGX6可以与Ezrin发生交互作用,参与鼻咽癌转移;(5)SPLUNC1基因的表达下调是鼻咽癌早期预警的分子诊断标志物.这些易感/抑瘤基因的功能基因组学研究为阐明鼻咽癌的发病机制打下了坚实的理论基础.     

人B淋巴细胞活化相关新基因的克隆

目的：分离新的与B细胞活化相关基因。方法：采用差异显示反转录PCR（DDRT－PCR）技术对人扁桃体活化和静止B细胞mRNA的差异表达进行分析。差异显示的片段经过Northern杂交验证后,作为探针进行人活化B细胞cDNA文库的筛选。结果：差异显示分析共获得明显的差异表达的标签序列(expressed sequence tag,EST)62条,其中主要在静止B细胞表达的有32条,在活化B细胞表达的有30条,经Northern 杂交验证,共获得阳性的片段25条,以在活化B细胞中高表达的EST30为探针,经3轮筛选人活化B细胞文库后获得1个新的全长为2048bp的cDNA克隆,该克隆含有1个630bp的开放读码框,其推断的氨基酸序列N端与酵母的动力蛋白KAR3部分同源,结论：克隆了1条可能与B细胞活化相关的新基因。     

肝细胞癌候选相关基因IDD01的克隆与鉴定

目的鉴定表达序列标签(EST)在肝细胞癌(HCC)和癌旁非癌组织表达,扩增其全长.方法采用半定量RT-PCR方法,对21例HCC患者的癌组织和癌旁非癌组织EST mRNA的表达情况进行检测,通过cDNA末端快速扩增(RACE)技术扩增、测序获得全长,Blast检索GenBank.结果此EST在HCC癌组织中高表达,癌旁非癌组织中低表达(P＜0.05);序列全长为1 333 bp,含有完整开放阅读框(ORF)和Poly(A)尾;Blast检索为一功能未知基因.结论获得一个和HCC相关候选新基因,为进一步研究其功能打下基础.     

双阳型梅花鹿脾脏细胞cDNA文库的构建和四个EST的发现

目的：开发和利用中国梅花鹿的基因资源,以期拥有一批梅花鹿基因的专利,并在专利保护下生产具有自己知识产权的基因工程药物。方法：用Trizol试剂提取梅花鹿脾脏细胞中的总RNA,分离得到mRNA后,用逆转录方法合成与mRNA互补的cDNA单链,再以此cDNA单链为模板,得到与该cDNA互补的另一条DNA链,将得到的DNA双链分子通过合适的Adapter连入pSPORT1质粒,将此重组质粒通过电转化方法导入E.coli DH5α菌,得到脾脏细胞的cDNA文库。筛选出阳性重组子,测序并分析得到的ESTS序列。结果：成功地构建了双阳型梅花鹿脾脏细胞cDNA文库;并对部分库容cDNA进行了克隆和测序,在这一过程中发现4个与已知基因同源的表达序列标签(ESTS),其中2个EST分别是梅花鹿视网膜母细胞瘤的同源基因和梅花鹿维生素K依赖性蛋白前体cDNA的部分序列。结论：通过构建cDNA文库的方法成功地得到了一批有价值的梅花鹿的基因片段。     

日本血吸虫真核生物翻译起始因子2α亚基全长cDNA的克隆与功能分析

目的 对用表达序列标签(EST)策略从日本血吸虫(Schistosoma japonicum)尾蚴cDNA文库中筛选出的新基因进行全长cDNA克隆及功能预测。方法 将插入于pTriplEx2质粒上的cDNA进行测序，测序结果经BLAS Tn程序搜索，发现该插入cDNA序列与曼氏血吸虫真核生物翻译起始因子2α亚基(eukaryotic translation initiation factor 2 alpha subunit，elF2α)基因高度同源。根据该EST序列设计与pTriplEx2质粒上的5′端测序引物相匹配的PCR下游引物，从该cDNA文库中扩出包含eIF2α全长ORF的cDNA片段。将PCR产物纯化后克隆到pGEM-T载体上，并对此克隆进行测序得到其全长cDNA序列。用NCBI站点的BLASTx及BLASTn程序对所获得的新基因序列进行同源性搜索；用blast two sequence程序对同源性高的基因进行核苷酸及氨基酸水平的同源性比较。同时用网上分析软件进行基序和保守区域的搜索。结果 发现一个与曼氏血吸虫eIF2α亚基mRNA高度同源的日本血吸虫新基因，核苷酸与氨基酸水平的同一性分别为87％和79％，编码由327个氨基酸组成的蛋白序列。结论 用EST策略筛选到一个日本血吸虫新基因，编码eIF2α亚基，全长编码序列与曼氏血吸虫eIF2α亚基mRNA高度同源。     

应用生物信息学方法筛选华支睾吸虫功能基因-Cdc42样蛋白

目的通过建立华支睾吸虫成虫cDNA文库,筛选其功能基因,以研制华支睾吸虫的药物靶标。方法应用SMART方法构建华支睾吸虫成虫cDNA文库,进行大量EST测序,然后应用生物信息学方法分析EST序列。结果从华支睾吸虫成虫cDNA文库中筛选出Cdc42样蛋白基因。结论应用生物信息学方法从华支睾吸虫成虫cDNA文库中筛选出Cdc42样蛋白基因。     

人类cyclophilin A基因cDNA的克隆和序列测定

目的:克隆人类环孢霉素A受体亚型cyclophilinA(CypA)基因,对该基因进行序列测定。方法:利用EST重叠序列拼排技术,设计特异性CypA引物,以人外周血白细胞总RNA为模板,进行RT-PCR扩增,纯化PCR产物,装pGEM-T载体,进行DNA序列测定。结果:成功克隆了人类Cyp A基因cDNA序列的开放阅读框,经DNA序列测定证实序列正确。结论:通过克隆人CypA基因,并克隆人pGEM-T载体,为下一步的基因表达和功能研究奠定了实验基础。     

人巨核白血病细胞诱导分化后差异表达基因的mRNA差别显示和克隆

目的：克隆巨核白血病细胞诱导分化后表达变化的mRNA，从中寻找对诱导分化起关键作用的基因，最终揭示巨核白血病细胞诱导分化的分子机制。方法：人巨核白血病细胞HIMeg经13-顺式维甲酸处理4 d后，收集细胞总RNA，进行mRNA差别显示、cDNA片段克隆和序列分析。结果：获得5个差示cDNA片段，经RNA点杂交分析后发现其中3个为假阳性，1个因没有杂交信号而无法确定，只有1个cDNA片段得到证实，其对应的mRNA在诱导分化后表达下降。该cDNA片段的核苷酸序列已在GenBank中登录，登录号为AF026526。结论：克隆到一个未知基因的cDNA片段，其全长cDNA序列、基因结构及生物功能有待进一步研究。     

Point mutation of 2.8 kb EcoRI fragment of the NPC transforming gene in NPC cell lines

Ｐｏｉｎｔｍｕｔａｔｉｏｎｏｆ２．８ｋｂＥｃｏＲＩｆｒａｇｍｅｎｔｏｆｔｈｅＮＰＣｔｒａｎｓｆｏｒｍｉｎｇｇｅｎｅｉｎＮＰＣｃｅｌｌｉｎｅｓＤｅｎｇＸｉｙｕｎ邓锡云，ＣａｏＹａ曹亚，ＣａｏＬｉ曹莉，ＬｅｏＭＬｅｅ黎民敬ａｎｄＹａｏＫａｉｔａｉ姚开泰Ｏ...     

A cDNA located on chromosome 7q32 shows loss of expression in epithelial cell line of nasopharyngeal carcinoma

ｅｔｈｏｄｓ　Ｔｈｅｇｅｎｏｔｙｐｅｓｏｆｐｏｌｙｍｏｒｐｈｉｃｍｉｃｒｏｓａｔｅｌｌｉｔｅｍａｒｋｅｒｓｏｎ 7ｑ32ｉｎＤＮＡｆｒｏｍ 2 4ｂｉｏｐｓｉｅｓｏｆｎａｓｏｐｈａｒｙｎｇｅａｌｃａｒｃｉｎｏｍａａｎｄｍａｔｃｈｅｄｎｏｒｍａｌｂｌｏｏｄｃｅｌｌｓｗｅｒｅｉｄｅｎｔｉｆｉｅｄ Ｔｈｅｅｘｐｒｅｓｓｉｏｎｌｅｖｅｌｓｏｆ 2 0ｅｘｐｒｅｓｓｅｄｓｅｑｕｅｎｃｅｔａｇｓ (ＥＳＴｓ)ｏｎ 7ｑ32ｂｅｔｗｅｅｎｈｕｍａｎｎａｓｏｐｈａｒｙｎｇｅａｌｃａｒｃｉｎｏｍａｅｐｉｔｈｅｌｉａｌ 1(ＨＮＥ1)ａｎ…     

一个新的基因转录本的克隆及序列分析

目的：筛选与精子发生和(或)睾丸发育相关的基因。方法：将不同发育阶段(胚胎和成人)的睾丸组织cDNA探针与人睾丸cDNA芯片进行杂交，通过杂交信号的比较，筛选出差异表达的基因。结果与结论：经测序发现该基因全长1316bp，包含1个1056bp的开放阅读框，编码351个氨基酸。生物信息学序列分析表明，它是p44S10基因家族的一条新的转录本基因，该基因的氨基酸序列编码一26S蛋白酶体调控亚基，在进化中高度保守，提示了该基因在生物体中的重要作用。     

正常肾上腺和嗜铬细胞瘤新全长基因的克隆及功能分析

目的 从正常肾上腺和嗜铬细胞瘤组织克隆新的全长cDNA并进行功能预测。方法 用表达序列标签（EST）测序、生物信息学分析、芯片拼接、cDNA末端快速护增及RT－PCR等方法检查104份来自正常肾上腺的样品及双份来自嗜铬细胞瘤的样品。结果 从肾上腺细胞文库中克隆全长cDNA126条,其中从正常肾上腺（AD）中克隆104条,嗜铬细胞瘤（PC）22条,通过测序获得克隆50条,电子克隆77条。2条通过RACE获得全长。95条经UniGene查询或放射杂交法（RH）作了染色体定位,根据预测功能其中包括一些重要的功能基因,包括信号蛋白、离子通道相关蛋白、参与激素合成酶类、分化相关蛋白、重要的转录因子及翻译启始因子等。7个由不同剪切方式而产生的新全长cDNA。表明在体内mRNA成熟过程中剪切方式的多样性及复杂性。结论 通过大规模EST测序结合生物信息学手段可在较短时间内从肾上腺组织文库中克隆127条新的全长cDNA,其中有些可能在肾上腺功能调控以及肿瘤发生中发挥重要作用。     

肝细胞癌中差异表达的表达序列标签的生物信息学分析

目的：采用生物信息学方法分析、预测在原发性肝细胞癌(HCC)中差异表达的表达序列标签(EST)的结构与功能,指导实验研究。方法：应用Blastn、SequencherTM、ORF Finder和DNASIS等软件分析肝细胞癌中差异表达的EST的全长、开放读码框、电子表达谱、染色体定位和编码蛋白质的功能。结果：获得2条新的cDNA全长序列;2条EST分别定位于2p13～15、3p14;高表达EST主要表达于肿瘤组织,低表达EST主要表达于正常组织;高表达基因编码蛋白质参与细胞信号转导、前mRNA加工和细胞骨架组装,低表达基因编码蛋白质与机体T淋巴细胞介导的免疫反应有关。结论：生物信息学技术有助于高效、快速地克隆、鉴定新基因。