In the present study, 89 porcine reproductive and respiratory syndrome virus(PRRSV) isolates in China during 2007 to 2012 were randomly selected from the GenBank genetic sequence database. Evolutionary characteristics...In the present study, 89 porcine reproductive and respiratory syndrome virus(PRRSV) isolates in China during 2007 to 2012 were randomly selected from the GenBank genetic sequence database. Evolutionary characteristics of these isolates were analyzed based on the sequences of non-struc-tural protein 2(Nsp2) and glycoprotein 5(GP5). The genetic variations of the isolates were also compared with six representative strains. The results showed that a high degree of genetic diversity exists among the PRRSV population in China. Highly pathogenic PRRSV isolates, with a discon-tinuous deletion of a 30 amino acid residue in the Nsp2 region, remained the most dominant virus throughout 2007–2012 in China. Owing to the extensive use of representative vaccine strains, natu-ral recombination events occurred between strains. Three isolates – HH08, DY, and YN-2011 – were more closely related to vaccine strains than the other isolates. Both YN-2011 and DY were the evolu-tionary products of recombination events between strains SP and CH-1R. The results of the present study provide useful information for the epidemiology of PRRSV as well as for vaccine development.展开更多
Research Aims: Obesity and type 2 diabetes are known to be associated with increased risk of various types of cancer. However, the molecular biological mechanism of how the risk of cancer is increased in obesity or ty...Research Aims: Obesity and type 2 diabetes are known to be associated with increased risk of various types of cancer. However, the molecular biological mechanism of how the risk of cancer is increased in obesity or type 2 diabetes is not known. The aim this research is to investigate if the decreased expression of p27Kip1, a cell cycle repressor protein, plays a central role in this mechanism. Research Methods, Previous Studies and Theoretical Backgrounds: It is well known that the expression of p27Kip1 is increased by numerous nutritional or chemopreventive anti-cancer agents. But it has never been known that the expression of p27Kip1 could be decreased, rather than increased, and the risk of cancer could be increased, rather than decreased. This problem was solved recently and this new analytical method was used in this study. Results: 1) The expression of p27Kip1 was indeed significantly decreased in human obese type 2 diabetic individuals relative to the lean normal controls. 2) The expression of p27Kip1 was also significantly decreased in genetically obese rodents relative to the lean normal controls. Additionally, in obese rodents, the concentrations of glucose or insulin were significantly increased relative to the lean normal controls. 3) Using human cells cultured in vitro it was found that the increased concentrations of glucose or insulin decrease the expression of p27Kip1. Conclusions: These results suggest that higher concentrations of glucose or insulin increase the risk of various types of cancer in obesity or type 2 diabetes by decreasing the expression of p27Kip1.展开更多
目的 探讨胃癌细胞中的乙醛脱氢酶2(ALDH2) m RNA发生可变剪接。方法 设计ALDH2基因特异性引物,用胃癌细胞(AGS、HGC-27、MKN45)、正常人胃黏膜上皮细胞GES-1和人外周全血白细胞提取RNA,进行逆转录聚合酶链反应(RT-PCR)扩增,然后对ALDH...目的 探讨胃癌细胞中的乙醛脱氢酶2(ALDH2) m RNA发生可变剪接。方法 设计ALDH2基因特异性引物,用胃癌细胞(AGS、HGC-27、MKN45)、正常人胃黏膜上皮细胞GES-1和人外周全血白细胞提取RNA,进行逆转录聚合酶链反应(RT-PCR)扩增,然后对ALDH2扩增产物进行测序分析;使用DNAStar软件分析ALDH2变异体(V)的开放阅读框(ORF)。结果 ALDH2变异体1(V1)外显子2和外显子4发生可变剪接,V1外显子1的3’端和外显子3的5’端3个不同的位点发生可变剪接,V1存在8个长度超过100氨基酸的ORF。结论 ALDH2 m RNA存在多种可变剪接形式,提示其存在复杂的蛋白表达功能。展开更多
Fibroblast growth factor (FGF) is a key regulator of developmental processes. A FGF homolog (vFGF) is found in all lepidopteran baculoviruses. Autographa californica nucleopolyhedrovirus (AcMNPV) and Bombyx mori NPV (...Fibroblast growth factor (FGF) is a key regulator of developmental processes. A FGF homolog (vFGF) is found in all lepidopteran baculoviruses. Autographa californica nucleopolyhedrovirus (AcMNPV) and Bombyx mori NPV (BmNPV) vFGFs are chemotactic factors. Here we analyzed the vfgf of Helicoverpa armigera NPV (HearNPV), a group II NPV. The HearNPV vfgf transcripts were detected from 18 to 96 h post-infection (hpi) of Hz-AM1 cells with HearNPV and encoded a 36 kDa protein, which was secreted into the culture medium. HearNPV vFGF had strong affinity to heparin, a property important for FGF signaling via an FGF receptor. Unlike its AcMNPV homolog, HearNPV vFGF specially chemoattracted Hz-AM1, but not other insect cells such as Sf9 and Se-UCR and not the mammalian cells 293 and HepG2. HearNPV vFGF is also associated with the envelope of BV but is absent in occlusion-derived virus, which coordinated to the chemotatic activity analysis.展开更多
基金supported by the Jilin Province Science and Technology Development Project(No.20140101123JC)the Fundamental Research Fund of Jilin Universitythe Program for Changjiang Scholars and Innovative Research Team in University(No.IRT1248)
文摘In the present study, 89 porcine reproductive and respiratory syndrome virus(PRRSV) isolates in China during 2007 to 2012 were randomly selected from the GenBank genetic sequence database. Evolutionary characteristics of these isolates were analyzed based on the sequences of non-struc-tural protein 2(Nsp2) and glycoprotein 5(GP5). The genetic variations of the isolates were also compared with six representative strains. The results showed that a high degree of genetic diversity exists among the PRRSV population in China. Highly pathogenic PRRSV isolates, with a discon-tinuous deletion of a 30 amino acid residue in the Nsp2 region, remained the most dominant virus throughout 2007–2012 in China. Owing to the extensive use of representative vaccine strains, natu-ral recombination events occurred between strains. Three isolates – HH08, DY, and YN-2011 – were more closely related to vaccine strains than the other isolates. Both YN-2011 and DY were the evolu-tionary products of recombination events between strains SP and CH-1R. The results of the present study provide useful information for the epidemiology of PRRSV as well as for vaccine development.
文摘Research Aims: Obesity and type 2 diabetes are known to be associated with increased risk of various types of cancer. However, the molecular biological mechanism of how the risk of cancer is increased in obesity or type 2 diabetes is not known. The aim this research is to investigate if the decreased expression of p27Kip1, a cell cycle repressor protein, plays a central role in this mechanism. Research Methods, Previous Studies and Theoretical Backgrounds: It is well known that the expression of p27Kip1 is increased by numerous nutritional or chemopreventive anti-cancer agents. But it has never been known that the expression of p27Kip1 could be decreased, rather than increased, and the risk of cancer could be increased, rather than decreased. This problem was solved recently and this new analytical method was used in this study. Results: 1) The expression of p27Kip1 was indeed significantly decreased in human obese type 2 diabetic individuals relative to the lean normal controls. 2) The expression of p27Kip1 was also significantly decreased in genetically obese rodents relative to the lean normal controls. Additionally, in obese rodents, the concentrations of glucose or insulin were significantly increased relative to the lean normal controls. 3) Using human cells cultured in vitro it was found that the increased concentrations of glucose or insulin decrease the expression of p27Kip1. Conclusions: These results suggest that higher concentrations of glucose or insulin increase the risk of various types of cancer in obesity or type 2 diabetes by decreasing the expression of p27Kip1.
文摘目的 探讨胃癌细胞中的乙醛脱氢酶2(ALDH2) m RNA发生可变剪接。方法 设计ALDH2基因特异性引物,用胃癌细胞(AGS、HGC-27、MKN45)、正常人胃黏膜上皮细胞GES-1和人外周全血白细胞提取RNA,进行逆转录聚合酶链反应(RT-PCR)扩增,然后对ALDH2扩增产物进行测序分析;使用DNAStar软件分析ALDH2变异体(V)的开放阅读框(ORF)。结果 ALDH2变异体1(V1)外显子2和外显子4发生可变剪接,V1外显子1的3’端和外显子3的5’端3个不同的位点发生可变剪接,V1存在8个长度超过100氨基酸的ORF。结论 ALDH2 m RNA存在多种可变剪接形式,提示其存在复杂的蛋白表达功能。
基金National Nature Science Foundations of China (30325002,30670077)National Basic Research Priorities Program of China (2003CB1140).
文摘Fibroblast growth factor (FGF) is a key regulator of developmental processes. A FGF homolog (vFGF) is found in all lepidopteran baculoviruses. Autographa californica nucleopolyhedrovirus (AcMNPV) and Bombyx mori NPV (BmNPV) vFGFs are chemotactic factors. Here we analyzed the vfgf of Helicoverpa armigera NPV (HearNPV), a group II NPV. The HearNPV vfgf transcripts were detected from 18 to 96 h post-infection (hpi) of Hz-AM1 cells with HearNPV and encoded a 36 kDa protein, which was secreted into the culture medium. HearNPV vFGF had strong affinity to heparin, a property important for FGF signaling via an FGF receptor. Unlike its AcMNPV homolog, HearNPV vFGF specially chemoattracted Hz-AM1, but not other insect cells such as Sf9 and Se-UCR and not the mammalian cells 293 and HepG2. HearNPV vFGF is also associated with the envelope of BV but is absent in occlusion-derived virus, which coordinated to the chemotatic activity analysis.
