同基因的

The inhibitor for DNA methyltransferase, 5-azacytidine (5-azaC), can demethylate the methylated DNA and restore transcription of genes. High dose homocystine can mediat DNA methylation and suppress gene expression.

应用甲基转移酶抑制剂5-氮杂胞苷(5-azacytidine， 5-azaC)可以使甲基化的启动子去甲基化，启动基因重新转录；高浓度同型半胱氨酸(homocystine， Hcy)可以介导基因甲基化而抑制其表达。

He mechanism underlined this effect may be linked to the demethylation of RIZ1 promoter.

的RIZ1 基因表达可能同RIZ1 基因启动子去甲基化作用有关。

The PSCA_3 fragment was selected for its superior expression level in eukaryotic cells.Then the sig-PSCA_3-Fc-GPI genetic fragment was cloned into pVAX1-neo-IRES-GM/B7 vector to construct the final immunological inhanced DNA vaccine pVAX1-PSCA_3-FcGB. Immunofluorescence and flow cytometry were used to confirm the expression of PSCA_3 fragment by transfected into Cos7 cell.Finally,the anti-tumor effect of pVAX1-PSCA_3-FcGB was tested in murine prostate cancer model generated by RM-1 cell line.The animal was immunized with pVAX1-PSCA_3-FcGB DNA vaccine by intramuscular injection plus electroporation,pVAX1 and pVAX1-PSCA_1-FcGB plasmid were used as control.The inhibitory effect of tumor was investigated by observion of forming time,volume and inhibition ratio of tumor.Results:DNA sequencing conformed that the heterological PSCA fusion antigen fragment which was synchronized by overlapping-extending-PCR,was consistent to design.Enzyme digestion analysis showed that the 1 to 4 copies heterological PSCA fusion antigen fragments were constructed successfully.

方法(1)检索GenBank，选择包含人主要T细胞抗原表位序列的人PSCA基因片段，应用异种化抗原设计技术，保留人T细胞抗原表位，设计异种化PSCA融合抗原片段；(2)根据核酸序列按中心模板法设计引物，应用重叠延伸PCR技术拼接合成异种化PSCA融合抗原片段基因，以PCR、限制性酶切和DNA序列测定法进行鉴定：(3)利用DNA限制性内切酶BssHⅡ和MluⅠ酶切后粘端互补的特点，采用同尾酶法构建1—4拷贝异种化PSCA融合抗原片段(PNCA_1-PSCA_4)，并将上述片段分别插入真核表达载体pCI-neo-Fc-GPI中，转染293T细胞，借助免疫荧光+流式细胞术考察插入片段表达效率，最终选定PSCA_3片段进行下一步研究；(4)将sig-PSCA_3-Fc-GPI基因片段自pCI-PSCA_3-Fc-GPI质粒上切下，插入pVAX1-neo-IRES—GM/B7载体中，构建免疫增效DNA疫苗pVAX1-PSCA_3-FcGB，并应用转染Cos7细胞+免疫荧光/流式细胞术方法鉴定其在真核细胞中的表达情况；(5)给8周龄雄性C57BL/6小鼠皮下种植RM-1细胞，制备小鼠前列腺癌模型，并采用股四头肌肌肉注射+电脉冲法(Electroporation，EP)接种DNA疫苗质粒pVAX1-PSCA_3-FcGB，同时接种pVAX1空载体质粒和pVAX1-PSCA_1-FcGB质粒作为对照，通过观察计算免疫动物的成瘤时间、肿瘤体积和抑瘤率，来评价该DNA疫苗在小鼠体内的抑瘤效果。

The results of phylogenetic trees and Southern blotting suggest all the nine strains of microsporidia are various species of the genus Nosema.

由微孢子虫ssurRNA基因序列同源性分析所构建的系统进化发育树及Southern杂交分析表明，这9种微孢子虫同为Nosema属，为同属不同种。

According to the alignment of Blastn and Blastx, one differentially exp ressed fragment, A7, was 97% identical in nucleotides to the 26S ribosomal RNA gene of Photinia fraseri and 91% in amino acids to cytochrome P450 monooxygenase in maize, respectively. Another differentially exp ressed fragment, A16, was 85% in nucleotides and 93% in amino acids identical to alpha-expansin 2 in Triphysaria versicolor.

核酸和氨基酸比对分析中同源性最高的是片段A7和A16.A7的核苷酸序列同源于红叶石楠Photinia fraseri 26S核糖体RNA (97%)、蛋白同源于玉米的细胞色素P450单加氧酶(91%)， A16的核苷酸(85%)及蛋白(93%)同源于直果草属 Triphysaria versicolor 的α-expansin 2基因。

The average percent value of G C (49.3%) was less than that of A T (50.7%), there was a bias of the content of G, T in the third codon; The number of transition G-A and T-C were 22, 15 respectively, which were higher than that of transition A-G and C-T, the number of tranversion C-A, T-G is 2 respectively, and other tranversion patterns didnt occur; the probability of transition was higher than that of tranversion , Ts/Tv = 9.5-19, there was the highest number of transition in the third codon. The gamma parameter a of the lst,nd and 3rd codon positions were 0.00572,0.01237 and 1.05239 respectively, they showed that there was adifferent substitution rate at different codon position. Frequences of synonymous codon usage were relatively biased. The average rates of synonymous and nonsynonymous substitution were 0.0787, 0.0011 respectively, there was a significant difference between dS and dN (Z = 4.713, p.01), and the low ratio( CD = 0.0284 .3) of dN/dS ratio impled that there were selective constraints against the nonsynonymous sites in cyt-b gene, The distribution of nonsynonymous codon substitution pattern related to Grantharm distance indicated that the purified selection at 2nd codon positions was more intensive than that at 1st codon positions. The phylogenetic trees supported the view of the double origin of Chinese goose, which means that domestic Chinese goose was derived from Anser cygnoides and domestic European goose, and Yili was derived from Anser anser.

碱基含量分析可知，序列的G C含量(49.3％)＜A T含量(50.7％)，密码子第三位点的G、T含量都有较强的偏倚性；序列间G→A和T→C的转换数(22次和15次)高于A→G和C→T的转换数(10次和9次)，C→A、T→G颠换数均为2次，其余颠换模式均未发生；转换数明显高于颠换数，Ts／Tv=9.5～19，密码子第三位点的转换数最高，呈现了相当强烈的转换偏倚性；密码子第一、二和三位点的gamma分布参数α值分别为0.00572、0.01237和1.05239，表明密码子第一位点的替换速率变异最大，第二位点次之，第三位点的替换速率变异相对较小；编码同一氨基酸的同义密码子并非随机使用，表现出一定程度的使用偏倚性；同义替换速率和非同义替换速率分别为0.0787和0.0011，dS与dN值间的差异极显著(Z=4.713，p＜0.01)，而ω=0.0284，明显小于0.3，表明雁属鹅细胞色素b基因序列经历了中度净化选择作用；单步非同义替换(Sing-step nonsymonymous codon substitution，SSNCS)分布模式与Grantharm距离之间的关系说明密码子的三个位点所受的净化选择强度不同；构建的最大简约树与邻接树拓扑结构一致，支持中国家鹅的双起源学说，即除伊犁鹅外的其它中国鹅品种起源于鸿雁，伊犁鹅和欧洲的郎德鹅、莱茵鹅起源于灰雁。

With the methods of Reverse transcription-PCR and cDNA sequencing, the expression of FHIT gene was detected in radiation carcinogenesis. The results show that: 1, The FHIT gene's sequence in normal BALB/c mice compare with the sequence of mice in Ge neBank which absents exon 3, but the function of FHIT protien doesn't alter.

结果发现：1、正常BALB／c 小鼠的FHIT基因序列同GeneBank中小鼠的FHIT基因序列比较缺少了外显子 3，但其表达的蛋白功能并未发生改变；2、FHIT基因在辐射损伤与辐射致癌的早期过程中，对照组血液、胸腺及骨髓均未出现异常的FHIT转录本的表达，不同剂量照射组中血液、胸腺及骨髓均有部分样品出现分子量较小的异常FHIT 转录本的表达。

Arabidopsis thaliana, a Cruciferous grass, is a model plant for molecular biology and has a close genetic relationship with brassicas. The genome sequencing was completed successfully al the end of 2000, which provided rich gene resource for biological research and application. Full use of these gene resources and searching the valuable genes for crop genetic improvement will become the targets of research.

拟南芥，是分子生物学研究的模式植物，与油菜同属于十字花科具有较近的亲缘关系。2000年底拟南芥全基因组测序工作的完成，为生物学的研究和应用提供了大量基因资源，充分挖掘这些基因资源以寻找有利用价值的基因应用于作物遗传改良将成为今后研究的重点。

In this thesis, using maize of same nucleus but different cytoplasms and same cytoplasm but different nuclei as the experimental materials, RNA editing of mitochondrial atp6 and cox2 gene in different tissues was analyzed.

本文以同核异质、同质异核48-2、黄早四两组玉米为材料，对不同器官组织线粒体的功能基因atp6、cox2进行了RNA编辑分析。

The 329 bp terminal inverted repeat sequence can't form the conserved fold-back secondary structure as that of many Streptomyces linear replicons. Lacking of typical Streptomyces tap/tpg locus for te-lomere replication, pPR2.3c encodes a protein with two domains resembling the telomere associated protein of Strepto-myces and helicase of Haemophilus respectively. No typical Streptomyces iteron-rep locus for replication from the cen-trally located origin, two DNA fragments containing almost all pPR2 were cloned and introduced by transformation into S.

其端粒末端反向重复序列的长度为329 bp，不能像多数链霉菌的线型质粒那样能形成保守的&折返&的二级结构。pPR2虽然没有参与链霉菌端粒复制的保守的tap/tpg基因，但是pPR2.3c基因编码了一个双结构域蛋白，分别同链霉菌的端粒复制相关蛋白Tap和嗜血杆菌的解旋酶具有相似性。pPR2缺少典型的链霉菌重复序列-复制基因区段，将几乎覆盖全长pPR2的两段DNA进行克隆后，不能转化变铅青链霉菌。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。