心脏特异性高表达hAPE1基因小鼠的构建与鉴定

本研究拟建立心脏特异性表达hAPE1转基因小鼠,为研究hAPE1基因功能及其突变与心脏发育和心血管疾病的关系提供工具动物。将人APE1(human APE1,hAPE1)基因插入到心脏特异性启动子α-肌球蛋白重链(α-MHC)下游,构建了心肌细胞特异性表达hAPE1的转基因表达载体,显微注射法导入C57BL/6J小鼠受精卵中,经胚胎移植获得转基因首建者小鼠,建立hAPE1转基因小鼠,PCR鉴定转基因小鼠基因型,Western blotting鉴定h APE1蛋白在心脏中的表达并筛选高表达的转基因品系。研究表明,将含有心肌细胞特异性α-MHC启动子和hAPE1基因的转基因载体进行显微注射于小鼠胚胎中,接着将胚胎移植入假孕母鼠的输卵管中发育,建立了心脏组织特异性高表达hAPE1转基因小鼠品系,获得子代小鼠40只。PCR检测发现有15只小鼠在其基因组上整合有hAPE1基因,Western blotting检测hAPE1在这些小鼠心脏中高度特异性表达。本研究成功获得了在小鼠心肌细胞中特异性表达hAPE1的转基因小鼠,为研究基因在心脏发育与相关疾病中的功能提供了有利的工具。     

Dkk3系统性表达转基因小鼠的建立

目的建立系统性表达Dkk3转基因模型小鼠,为研究Dkk3生理功能及对骨生长发育的作用提供工具动物。方法通过ISH来观察Dkk3于C57BL/6J小鼠全身组织中的表达。把Dkk3基因插入系统性表达CMV启动子下游,构建转基因表达载体,显微注射法建立C57BL/6J Dkk3转基因小鼠。PCR鉴定转基因小鼠的基因型,RT-PCR检测Dkk3在骨髓中的表达,Western Blot检测Dkk3在肺脏、脑及肝脏中的表达,BrdU标记染色观察转基因小鼠骨生长情况。结果在生理状态下,Dkk3基因广泛表达,在骨、心脏及脑等组织高表达。建立的2个转基因小鼠品系中,转入的Dkk3基因在骨髓、脑、肝脏及肺组织中均有明显表达。BrdU整合率实验显示转基因小鼠长骨骺区细胞增殖明显低于同龄对照小鼠。结论建立了系统性表达Dkk3转基因小鼠,转入的Dkk3基因明显抑制小鼠长骨骨骺区细胞增殖,为Dkk3对骨生长发育的作用研究提供了有价值的工具动物。     

Cramp转基因小鼠的构建及鉴定

目的建立系统性表达Cramp转基因模型小鼠,为研究Cramp在衰老中的作用提供模型动物。方法把Cramp cDNA插入系统性表达CMV启动子下游,构建转基因表达载体,显微注射法建立Cramp转基因小鼠。PCR鉴定转基因小鼠的基因型,用RT-PCR和Western blotting方法筛选高表达品系。结果成功构建Cramp cDNA转基因载体,建立了Cramp转基因小鼠,通过RT-PCR和Western blotting方法筛选出3个高表达品系。结论建立了系统表达Cramp转基因小鼠,转入的Cramp基因在骨髓、脾脏、肝脏等组织高表达,为研究Cramp基因在衰老中的作用及机制提供了动物模型。     

肥大软骨细胞特异性表达Cre重组酶转基因小鼠的建立

肥大软骨细胞是软骨细胞的终末分化形式,在软骨内成骨过程中发挥十分关键的作用。为了研究肥大软骨细胞在骨骼发育过程中的功能,我们构建了在8.2 kb小鼠X型胶原基因（Col10a1）启动子控制下表达Cre重组酶的转基因小鼠品系（Col10a1-8.2-Cre）。采用显微注射法将11.5 kb的转基因片段引入小鼠基因组,共注射受精卵328枚,获得子代鼠51只,经PCR基因型鉴定有3只在基因组上整合有Cre重组酶基因。PCR检测发现Col10a1-8.2-Cre转基因在含有肥大软骨细胞的组织中表达。为了检测Cre重组酶表达的强度和组织特异性,转基因小鼠与ROSA26报告小鼠交配。子代ROSA26;Col10a1-8.2-Cre双转基因小鼠LacZ染色检测的结果显示,Cre重组酶在所有的肥大软骨细胞中表达。原位杂交的结果验证Col10a1-8.2-Cre转基因表达在肥大区的上端。以上结果表明,我们建立的肥大软骨细胞特异性表达Cre重组酶的转基因小鼠品系可以作为一种遗传学工具,介导目的基因在肥大软骨细胞中的敲除。     

心脏特异表达Dhcr24转基因小鼠的建立和表型分析

目的建立心脏特异表达小鼠24-脱氢胆固醇还原酶基因（Dhcr24）转基因小鼠,研究该基因在心脏中表达对小鼠心脏发育,形态和功能维持中的作用。方法RT-PCR法克隆小鼠24-脱氢胆固醇还原酶基因,把Dhcr24基因插入-αMHC启动子下游,构建转基因表达载体,通过显微注射法建立Dhcr24 C57BL/6J转基因小鼠。并利用特异引物PCR法鉴定转基因小鼠的基因型,RT-PCR和Western Blotting检测基因表达水平,光学显微镜和超声检测不同月龄Dhcr24转基因小鼠心脏的组织结构改变。结果建立了2个品系的心脏特异表达Dhcr24转基因小鼠。转入的Dhcr24基因在心脏组织的表达水平超过内源性Dhcr24的3倍。心脏组织学和超声检查证实：Dhcr24转基因小鼠的心室壁变厚,心腔变小,但心脏功能保持正常。结论成功建立了心脏特异表达Dhcr24转基因小鼠,Dhcr24基因在心脏组织的过度表达对小鼠心脏发育和功能维持中的作用需要进一步探讨。     

特异性检测胰腺组织表达Cre重组酶转基因小鼠的方法

利用组织特异性分子标志物启动子调控Cre重组酶,研制了6种在不同组织中特异性表达Cre重组酶的转基因小鼠.这些转基因小鼠的基因型鉴定均使用设计在Cre基因编码区的通用引物.为了特异性检测胰腺组织表达Cre重组酶的转基因小鼠,在大鼠胰岛素RIP启动子上和Cre基因上设计1对引物进行PCR扩增,并通过凝胶电泳进行分析.PCR结果显示,设计在Cre基因上的通用引物可以从6种不同组织特异性Cre重组酶转基因小鼠基因组DNA中扩增获得480 bp产物;利用本研究设计的特异性引物可以从胰腺组织表达Cre重组酶转基因小鼠基因组DNA中扩增200 bp的目的条带.这一结果表明,利用特异性引物进行PCR反应,可有效地将胰腺组织表达Cre重组酶转基因小鼠与其他多种组织的Cm重组酶转基因小鼠鉴别开来.     

广泛表达人载脂蛋白E3转基因小鼠的建立

目的建立人载脂蛋白E3（apolipoprotein E3,ApoE3）转基因小鼠,研究该基因在多种组织中表达水平的变化对动物的影响,探索该基因的功能。方法RT-PCR法克隆人ApoE3基因,把该基因插入CMV启动子下游,构建转基因表达载体,通过显微注射法建立转ApoE3基因C57BL／6J小鼠。并利用特异引物PCR法鉴定转基因小鼠的基因型,Western blot检测基因表达水平。通过生化指标分析初步鉴定ApoE3基因的功能。结果建立了2个系的高表达人ApoE3转基因小鼠。结论成功建立了CMV启动子启动的高表达人ApoE3基因转基因小鼠,为进一步探索该基因的功能奠定了基础。     

人载脂蛋白C3基因转基因小鼠的建立及血脂变化分析

目的制备系统性表达人载脂蛋白C3（APOC3）基因的转基因小鼠,建立高血脂小鼠模型。方法将人APOC3基因插入系统性表达启动子下游,构建转基因表达载体,通过显微注射法建立人APOC3转基因C57BL/6J小鼠。并利用特异引物PCR法鉴定转基因小鼠的基因型,Western blot检测基因表达水平,血生化分析检测不同月龄转基因小鼠与同龄野生型小鼠的血脂指标,脂肪染色观察肝脏脂肪水平。结果建立了高表达人APOC3基因的转基因小鼠品系;转入的人APOC3基因在血液、肝脏、小肠、肌肉、心脏、肾脏、脾脏中均有明显表达;不同月龄转基因小鼠的血浆甘油三酯水平明显高于同龄野生型小鼠;转基因小鼠的肝脏脂肪含量高于野生型小鼠。结论系统性表达人APOC3基因的转基因小鼠表现高脂血症表型,可以作为高血脂以及高血脂相关的心血管病的工具动物。     

Dkk3心脏特异表达转基因小鼠心脏功能分析

目的建立心脏特异表达Dkk3转基因模型小鼠,研究Dkk3对心脏发育及和心肌病的调节作用。方法把Dkk3基因插入心肌特异启动子-αMHC下游,构建转基因表达载体,显微注射法建立C57BL/6J Dkk3转基因小鼠,PCR鉴定转基因小鼠基因型,采用Northern blot检测Dkk3在心脏组织中的表达,HE染色和超声检查转基因小鼠心脏结构和功能。结果建立了3个不同表达水平的Dkk3转基因小鼠品系。转入的Dkk3基因在心脏组织的表达水平均高于同龄对照小鼠。组织学分析显示Dkk3小鼠室壁变厚,心腔减小,心肌细胞排列轻度紊乱。超声检查显示心室壁变厚,收缩期容积和舒张期容积显著减小,射血分数,短轴缩短率增加。结论Dkk3过表达导致转基因小鼠室壁变厚,心腔减小,心肌细胞排列轻度紊乱,心肌舒张功能轻度失调。     

神经组织特异表达CTF1转基因小鼠的建立

目的建立神经组织特异表达CTF1的转基因模型小鼠,为研究CTF1生物学功能及与老年痴呆等疾病发病机制的关系提供工具动物。方法把CTF1基因插入神经组织特异的启动子PDGF下游,构建转基因表达载体,显微注射法建立C57BL/6J CTF1转基因小鼠。PCR鉴定转基因小鼠基因型,采用Western Blot方法鉴定CTF1在脑组织中的表达,对转基因小鼠脑组织进行石蜡切片,HE染色,显微镜观察组织结构形态的改变。结果建立了2个不同表达水平的CTF1转基因小鼠品系。转入的CTF1基因在脑组织的表达水平均高于同龄对照小鼠。组织学分析显示CTF1转基因小鼠大小脑组织基本结构形态未见异常。结论成功建立了稳定遗传的神经组织特异表达CTF1转基因小鼠品系,为CTF1的生物学功能及与老年痴呆等疾病发病机制关系的研究提供了有力的模型工具。     

Human CD2 3'-flanking sequences confer high-level, T cell-specific, position-independent gene expression in transgenic mice

We have localized a set of T cell-specific DNAase I hypersensitive sites in the 3'-flanking region of the human CD2 gene. A 5.5 kb BamHI-XbaI fragment containing these DNAase I hypersensitive sites conferred efficient, copy number-dependent, T cell-specific expression of a linked human CD2 minigene, independent of the position of integration in the transgenic mouse genome. When linked to the mouse Thy-1.1 gene or the human beta-globin gene, this fragment conferred the same T cell-specific expression, independent of its orientation. These results suggest that this flanking region is both necessary and sufficient for full tissue-specific activation of homologous and heterologous genes in transgenic mice.     

Pol II-expressed shRNA knocks down Sod2 gene expression and causes phenotypes of the gene knockout in mice

RNA interference (RNAi) has been used increasingly for reverse genetics in invertebrates and mammalian cells, and has the potential to become an alternative to gene knockout technology in mammals. Thus far, only RNA polymerase III (Pol III)-expressed short hairpin RNA (shRNA) has been used to make shRNA-expressing transgenic mice. However, widespread knockdown and induction of phenotypes of gene knockout in postnatal mice have not been demonstrated. Previous studies have shown that Pol II synthesizes micro RNAs (miRNAs)-the endogenous shRNAs that carry out gene silencing function. To achieve efficient gene knockdown in mammals and to generate phenotypes of gene knockout, we designed a construct in which a Pol II (ubiquitin C) promoter drove the expression of an shRNA with a structure that mimics human miRNA miR-30a. Two transgenic lines showed widespread and sustained shRNA expression, and efficient knockdown of the target gene Sod2. These mice were viable but with phenotypes of SOD2 deficiency. Bigenic heterozygous mice generated by crossing these two lines showed nearly undetectable target gene expression and phenotypes consistent with the target gene knockout, including slow growth, fatty liver, dilated cardiomyopathy, and premature death. This approach opens the door of RNAi to a wide array of well-established Pol II transgenic strategies and offers a technically simpler, cheaper, and quicker alternative to gene knockout by homologous recombination for reverse genetics in mice and other mammalian species.     

Silencing of the mineralocorticoid receptor by ribonucleic acid interference in transgenic rats disrupts endocrine homeostasis

Currently, gene disruption by homologous recombination in embryonic stem cells is only feasible in mice. To circumvent this problem, we silenced mineralocorticoid receptor (MR) expression by RNA interference in knockdown rats generated through lentiviral transgenesis. Analysis of the F1 progeny at 3 wk of age revealed strongly decreased MR levels. This was specific for the targeted gene and related to the abundance of the short interfering RNA. Reminiscent of MR knockout mice, the transgenic rats showed a reduced body weight, elevated serum aldosterone levels, increased plasma renin activity, and altered expression of MR target genes. Some of these effects correlated with the degree to which MR mRNA expression was reduced. Whereas disruption of the MR by gene targeting in mice leads to postnatal death, our strategy also allowed obtaining adult knockdown rats with defects in hormone and electrolyte homeostasis resembling pseudohypoaldosteronism. In conclusion, this is the first example of a human disease model based on RNA interference in rats.     

Tissue-specific and hormonally regulated expression of a rat alpha 2u globulin gene in transgenic mice.

To investigate the tissue-specific and hormonal regulation of the rat alpha 2u globulin gene family, we introduced one cloned member of the gene family into the mouse germ line and studied its expression in the resulting transgenic mice. Alpha 2u globulingene 207 was microinjected on a 7-kilobase DNA fragment, and four transgenic lines were analyzed. The transgene was expressed at very high levels, specifically in the liver and the preputial gland of adult male mice. The expression in male liver was first detected at puberty, and no expression was detected in female transgenic mice. This pattern of expression is similar to the expression of endogenous alpha 2u globulin genes in the rat but differs from the expression of the homologous mouse major urinary protein (MUP) gene family in that MUPs are synthesized in female liver and not in the male preputial gland. We conclude that these differences between rat alpha 2u globulin and mouse MUP gene expression are due to evolutionary differences in cis-acting regulatory elements. The expression of the alpha 2u globulin transgene in the liver was abolished by castration and fully restored after testosterone replacement. The expression could also be induced in the livers of female mice by treatment with either testosterone or dexamethasone, following ovariectomy and adrenalectomy. Therefore, the cis-acting elements responsible for regulation by these two hormones, as well as those responsible for tissue-specific expression, are closely linked to the alpha 2u globulin gene.     

心脏特异表达NOL3转基因小鼠的建立

目的建立心脏特异表达NOL3转基因小鼠,用于研究该基因在心肌病发病中的作用。方法Western blot检测小鼠NOL3表达谱。构建aMHC-NOL3表达载体,显微注射法建立NOL3转基因小鼠。PCR鉴定转基因鼠的基因型,心脏超声检测转基因及野生型小鼠心脏功能及几何构型。结果NOL3在1月龄野生型鼠心脏、脑、骨骼肌中的高表达,在心脏中的表达不随年龄而改变。通过转基因小鼠的筛选,得到了3个NOL3转基因品系,其中1个品系心脏NOL3蛋白表达量与野生型鼠相比明显增加。单转NOL3基因的小鼠心脏功能及几何构型与野生型小鼠相比无显著变化。结论成功建立了心脏特异表达NOL3转基因小鼠,为进一步和心肌病小鼠模型杂交,研究该基因在心肌病发病中的作用提供了工具。