目的建立全身表达24-脱氢胆固醇还原酶基因(Dhcr24)转基因小鼠动物模型,研究该基因过表达对小鼠代谢的影响。方法RT-PCR法克隆小鼠Dhcr24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Dhcr24转基因小鼠。PCR鉴...目的建立全身表达24-脱氢胆固醇还原酶基因(Dhcr24)转基因小鼠动物模型,研究该基因过表达对小鼠代谢的影响。方法RT-PCR法克隆小鼠Dhcr24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Dhcr24转基因小鼠。PCR鉴定Dhcr24转基因小鼠的基因型,RT-PCR和Western Blot检测基因表达水平,血生化检测仪检测转基因小鼠血生化指标的改变。结果建立了2个不同表达水平的Dhcr24转基因小鼠品系,转入的Dhcr24基因在肝和脾组织中的表达高于内源的Dhcr24。血生化检测证实:乳酸脱氢酶(LDH)、总蛋白(TP)、白蛋白(Alb)和血肌酐(SCr)较野生型小鼠明显降低,而高密度脂蛋白胆固醇(HDL-c)和碱性磷酸酶(ALP)较野生型小鼠明显增加,并且Dhcr24转基因雌鼠的体重比野生型小鼠明显降低,均有显著差异。但Dhcr24转基因雄鼠各项指标与野生型小鼠相比没有显著差异。结论成功建立了全身表达Dhcr24转基因小鼠,并证实Dhcr24基因对雌性小鼠的体重和血生化指标,包括LDH,TP,Alb,SCr,HDL-c and ALP具有明显的影响。展开更多
Background: Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive malformation syndrome characterized by a disorder in cholesterol metabolism. SLOS is caused by mutations in the DHCR7 gene which encodes 7-dehydr...Background: Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive malformation syndrome characterized by a disorder in cholesterol metabolism. SLOS is caused by mutations in the DHCR7 gene which encodes 7-dehydrocholesterol reductase, an enzyme that catalyses the final step in cholesterol biosynthesis. We have previously established the clinical and photobiological features of the photosensitivity that is frequently a feature of SLOS. Objectives: In this study, we have performed mutational analysis of the DHCR7 gene in individuals from five fa milies with SLOS. In each family, one member was affected by severe photosensiti vity as a manifestation of SLOS. Methods: Fifteen samples (including family cont rols)-were screened using polymerase chain reaction amplification and direct au tomated sequencing. Results: Six different DHCR7 mutations were identified of wh ich five were single point mutations that causedmissense amino acid substitution s (P51H, T93M, L99P, E448K and R450L). The other was a splice site mutation (G →C in splice acceptor site) affecting the intron 8-exon 9 splice junction (IVS 8-1G→C). This splice sitemutation and four of the five missense mutations have been previously published as causal in SLOS but the P51H is a novel mutation wh ich has not previously been reported. Conclusions: This is the first study in wh ich DHCR7 gene mutational analysis has been performed on SLOS subjects with seve re photosensitivity and indicates that no single mutation is responsible for the photosensitivity which characterizes this disorder.展开更多
文摘目的建立全身表达24-脱氢胆固醇还原酶基因(Dhcr24)转基因小鼠动物模型,研究该基因过表达对小鼠代谢的影响。方法RT-PCR法克隆小鼠Dhcr24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Dhcr24转基因小鼠。PCR鉴定Dhcr24转基因小鼠的基因型,RT-PCR和Western Blot检测基因表达水平,血生化检测仪检测转基因小鼠血生化指标的改变。结果建立了2个不同表达水平的Dhcr24转基因小鼠品系,转入的Dhcr24基因在肝和脾组织中的表达高于内源的Dhcr24。血生化检测证实:乳酸脱氢酶(LDH)、总蛋白(TP)、白蛋白(Alb)和血肌酐(SCr)较野生型小鼠明显降低,而高密度脂蛋白胆固醇(HDL-c)和碱性磷酸酶(ALP)较野生型小鼠明显增加,并且Dhcr24转基因雌鼠的体重比野生型小鼠明显降低,均有显著差异。但Dhcr24转基因雄鼠各项指标与野生型小鼠相比没有显著差异。结论成功建立了全身表达Dhcr24转基因小鼠,并证实Dhcr24基因对雌性小鼠的体重和血生化指标,包括LDH,TP,Alb,SCr,HDL-c and ALP具有明显的影响。
文摘Background: Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive malformation syndrome characterized by a disorder in cholesterol metabolism. SLOS is caused by mutations in the DHCR7 gene which encodes 7-dehydrocholesterol reductase, an enzyme that catalyses the final step in cholesterol biosynthesis. We have previously established the clinical and photobiological features of the photosensitivity that is frequently a feature of SLOS. Objectives: In this study, we have performed mutational analysis of the DHCR7 gene in individuals from five fa milies with SLOS. In each family, one member was affected by severe photosensiti vity as a manifestation of SLOS. Methods: Fifteen samples (including family cont rols)-were screened using polymerase chain reaction amplification and direct au tomated sequencing. Results: Six different DHCR7 mutations were identified of wh ich five were single point mutations that causedmissense amino acid substitution s (P51H, T93M, L99P, E448K and R450L). The other was a splice site mutation (G →C in splice acceptor site) affecting the intron 8-exon 9 splice junction (IVS 8-1G→C). This splice sitemutation and four of the five missense mutations have been previously published as causal in SLOS but the P51H is a novel mutation wh ich has not previously been reported. Conclusions: This is the first study in wh ich DHCR7 gene mutational analysis has been performed on SLOS subjects with seve re photosensitivity and indicates that no single mutation is responsible for the photosensitivity which characterizes this disorder.
