目的探讨乙型肝炎病毒DNA多聚酶(HBV DNA P)结构域蛋白RNase H对细胞凋亡易感基因(CAS)的转录激活作用。方法以HBV DNA P结构域蛋白RNase H的反式调节因子的基因表达谱芯片结果为基础,利用生物信息学技术确定CAS的启动子区域(CASp),扩增...目的探讨乙型肝炎病毒DNA多聚酶(HBV DNA P)结构域蛋白RNase H对细胞凋亡易感基因(CAS)的转录激活作用。方法以HBV DNA P结构域蛋白RNase H的反式调节因子的基因表达谱芯片结果为基础,利用生物信息学技术确定CAS的启动子区域(CASp),扩增CASp并克隆至真核报告载体pCAT3-Basic中,构建pCAT3-CASp报告载体。分别以该质粒单独或与pcDNA3.1(-)-RH共转染肝癌细胞系HepG2细胞,ELISA法检测氯霉素乙酰转移酶(CAT)的表达活性,并以pCAT3-Basic空载体、pCAT3-TXNRD1p分别转染HepG2细胞作为阴性和阳性对照。结果pCAT3-CASp和pcDNA3.1(-)-RH瞬时共转染的HepG2细胞的CAT表达活性是pCAT3-CASp的1.5倍,是pCAT3-Basic空载体的2.7倍。结论本实验进一步验证了我室利用基因表达谱技术研究RNase H蛋白反式激活作用的结果。我室克隆的CAS启动子具有顺式激活下游基因的活性;HBV的RNase H蛋白具有对CAS的反式激活作用。展开更多
A genetic association between single nucleotide polymorphisms (SNPs) and pulmonary hypertension syndrome (PHS) was established in a commercial population of broiler chickens. The associated SNPs were found in the NOS3...A genetic association between single nucleotide polymorphisms (SNPs) and pulmonary hypertension syndrome (PHS) was established in a commercial population of broiler chickens. The associated SNPs were found in the NOS3 and HIF1α genes (LOD > 6;p NOS3 gene interfere with its trans-activation and transcriptional activation activities under natural hypobaric hypoxia conditions and are located in a consensus sequence that is called the hypoxia response element (HRE). SNPs located in the HIF1α gene could act as alternative cryptic splicing sites in intron six, which may stimulate non-sense mediated early decay (NMD) of the primary transcript. A fragment of intron 3 of the EDN1 gene was also evaluated, but the polymorphisms found were not associated with PHS (lod 0.001). However, further studies on the regulatory transcription sequences of EDN1 are recommended. The findings of this study indicate that intronic sequences should be included when searching for polymorphisms that produce physiological changes. Introns have transcriptional regulatory sequences or post-transcriptional control signals, which are known as cis- and trans-activation regulatory elements and are able to alter the physiological processes of hypoxia adaptation when modified. Based on these findings, it can be concluded that the inheritance pattern of PHS is autosomal overdominant and has deleterious effects that are characterized by higher penetrance in heterozygous than in homozygous animals, which prevent broiler chickens from being able to adapt to high altitudes.展开更多
The hexanucleotide repeat mutation in the intron-1 of the chromosome 9 open reading frame (C9orf72) is a frequent cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Altered RNA folding pla...The hexanucleotide repeat mutation in the intron-1 of the chromosome 9 open reading frame (C9orf72) is a frequent cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Altered RNA folding plays a role in ALS pathogenesis in two ways: non-ATG translation of the repeat can lead to aggregates of the known C9orf72 specific dipeptide polymer, whereas the repeat also can form neurotoxic RNA inclusions that dose-responsively kill motor neurons. We report the presence of a homology in the 5’untranslated region (UTR) of the messenger RNA encoding C9orf72 with the iron responsive elements (IRE) that control expression of iron-associated transcripts and predict that this RNA structure may iron-dependently regulate C9orf72 translation. We previously report altered serum ferritin levels track with severity of ALS in patients. Here, we conduct bioinformatics analyses to determine the secondary structure of the 5’UTR in C9orf72 mRNA and find it aligned with IREs in the human mitochondrial cis-aconitase and L and H-ferritin transcripts. Comparison of the role of RNA repeats in Friedriech’s ataxia and fragile X mental retardation suggests the utility of RNA based therapies for treatment of ALS. Antisense oligonucleotides (ASO) have been reported to therapeutically target these GGGGCC repeats. At the same time, because the function of C9orf72 is unknown, knockdown strategies carry some risk of inducing or compounding haploinsufficiency. We propose, for consideration, an approach that may enhance its therapeutic dynamic range by increasing the 5’UTR driven translation of C9orf72 protein to compensate for any potential ALS-specific or ASO-induced haploinsufficieny.展开更多
Th1-response plays a crucial role in determining pathogenesis of organ-specific autoimmune diseases. It is believed that both IL-12 and INF-alpha are initiators to regulate Th1-response. In our experimental autoimmune...Th1-response plays a crucial role in determining pathogenesis of organ-specific autoimmune diseases. It is believed that both IL-12 and INF-alpha are initiators to regulate Th1-response. In our experimental autoimmune uveitis (EAU) model, both Lewis and Fischer 344 rats share the same MHC class II molecules, while Lewis rat is EAU susceptible and Fischer 344 rat is EAU resistant. However, under the same condition of immunization, if pertussis toxin (PTX) was injected intraperitoneally as an additional adjuvant, Fischer 344 rat can develop EAU. In this study we investigate which mechanisms are involved in the induction of EAU in CFA+R16+PTX-treated (CRP-treated) Fischer 344 rats. In vivo and in vitro data demonstrated that Th1-cytokine, IFN-gamma mRNA expression was significantly increased in disease target tissue-eyes and in draining lymph node cells of CRP-treated Fischer 344 rat. When IL-12 and IFN-alpha mRNA expression were compared in the experimental groups, only IFN-alpha mRNA expression was associated with EAU development. To distinguish the sources of IFN-alpha producing cells, it was observed that IFN-alpha expression was mainly produced by macrophages. It was further confirmed that normal macrophage from Fischer 344 rat was able to produce significant IFN-alpha in the presence of PTX. The data strongly suggested that IFN-alpha might be involved in initiating Th1-cell differentiation and in turn contribute to the induction of EAU. High IFN-alpha expression induced by PTX may represent a novel pathway to initiate Th1 response in Fischer 344 rat.展开更多
文摘目的探讨乙型肝炎病毒DNA多聚酶(HBV DNA P)结构域蛋白RNase H对细胞凋亡易感基因(CAS)的转录激活作用。方法以HBV DNA P结构域蛋白RNase H的反式调节因子的基因表达谱芯片结果为基础,利用生物信息学技术确定CAS的启动子区域(CASp),扩增CASp并克隆至真核报告载体pCAT3-Basic中,构建pCAT3-CASp报告载体。分别以该质粒单独或与pcDNA3.1(-)-RH共转染肝癌细胞系HepG2细胞,ELISA法检测氯霉素乙酰转移酶(CAT)的表达活性,并以pCAT3-Basic空载体、pCAT3-TXNRD1p分别转染HepG2细胞作为阴性和阳性对照。结果pCAT3-CASp和pcDNA3.1(-)-RH瞬时共转染的HepG2细胞的CAT表达活性是pCAT3-CASp的1.5倍,是pCAT3-Basic空载体的2.7倍。结论本实验进一步验证了我室利用基因表达谱技术研究RNase H蛋白反式激活作用的结果。我室克隆的CAS启动子具有顺式激活下游基因的活性;HBV的RNase H蛋白具有对CAS的反式激活作用。
文摘A genetic association between single nucleotide polymorphisms (SNPs) and pulmonary hypertension syndrome (PHS) was established in a commercial population of broiler chickens. The associated SNPs were found in the NOS3 and HIF1α genes (LOD > 6;p NOS3 gene interfere with its trans-activation and transcriptional activation activities under natural hypobaric hypoxia conditions and are located in a consensus sequence that is called the hypoxia response element (HRE). SNPs located in the HIF1α gene could act as alternative cryptic splicing sites in intron six, which may stimulate non-sense mediated early decay (NMD) of the primary transcript. A fragment of intron 3 of the EDN1 gene was also evaluated, but the polymorphisms found were not associated with PHS (lod 0.001). However, further studies on the regulatory transcription sequences of EDN1 are recommended. The findings of this study indicate that intronic sequences should be included when searching for polymorphisms that produce physiological changes. Introns have transcriptional regulatory sequences or post-transcriptional control signals, which are known as cis- and trans-activation regulatory elements and are able to alter the physiological processes of hypoxia adaptation when modified. Based on these findings, it can be concluded that the inheritance pattern of PHS is autosomal overdominant and has deleterious effects that are characterized by higher penetrance in heterozygous than in homozygous animals, which prevent broiler chickens from being able to adapt to high altitudes.
文摘The hexanucleotide repeat mutation in the intron-1 of the chromosome 9 open reading frame (C9orf72) is a frequent cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Altered RNA folding plays a role in ALS pathogenesis in two ways: non-ATG translation of the repeat can lead to aggregates of the known C9orf72 specific dipeptide polymer, whereas the repeat also can form neurotoxic RNA inclusions that dose-responsively kill motor neurons. We report the presence of a homology in the 5’untranslated region (UTR) of the messenger RNA encoding C9orf72 with the iron responsive elements (IRE) that control expression of iron-associated transcripts and predict that this RNA structure may iron-dependently regulate C9orf72 translation. We previously report altered serum ferritin levels track with severity of ALS in patients. Here, we conduct bioinformatics analyses to determine the secondary structure of the 5’UTR in C9orf72 mRNA and find it aligned with IREs in the human mitochondrial cis-aconitase and L and H-ferritin transcripts. Comparison of the role of RNA repeats in Friedriech’s ataxia and fragile X mental retardation suggests the utility of RNA based therapies for treatment of ALS. Antisense oligonucleotides (ASO) have been reported to therapeutically target these GGGGCC repeats. At the same time, because the function of C9orf72 is unknown, knockdown strategies carry some risk of inducing or compounding haploinsufficiency. We propose, for consideration, an approach that may enhance its therapeutic dynamic range by increasing the 5’UTR driven translation of C9orf72 protein to compensate for any potential ALS-specific or ASO-induced haploinsufficieny.
文摘Th1-response plays a crucial role in determining pathogenesis of organ-specific autoimmune diseases. It is believed that both IL-12 and INF-alpha are initiators to regulate Th1-response. In our experimental autoimmune uveitis (EAU) model, both Lewis and Fischer 344 rats share the same MHC class II molecules, while Lewis rat is EAU susceptible and Fischer 344 rat is EAU resistant. However, under the same condition of immunization, if pertussis toxin (PTX) was injected intraperitoneally as an additional adjuvant, Fischer 344 rat can develop EAU. In this study we investigate which mechanisms are involved in the induction of EAU in CFA+R16+PTX-treated (CRP-treated) Fischer 344 rats. In vivo and in vitro data demonstrated that Th1-cytokine, IFN-gamma mRNA expression was significantly increased in disease target tissue-eyes and in draining lymph node cells of CRP-treated Fischer 344 rat. When IL-12 and IFN-alpha mRNA expression were compared in the experimental groups, only IFN-alpha mRNA expression was associated with EAU development. To distinguish the sources of IFN-alpha producing cells, it was observed that IFN-alpha expression was mainly produced by macrophages. It was further confirmed that normal macrophage from Fischer 344 rat was able to produce significant IFN-alpha in the presence of PTX. The data strongly suggested that IFN-alpha might be involved in initiating Th1-cell differentiation and in turn contribute to the induction of EAU. High IFN-alpha expression induced by PTX may represent a novel pathway to initiate Th1 response in Fischer 344 rat.
