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基于episomal CRISPR/Cas9载体的基因敲入方法
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作者 邹征伟 赖兴强 李伟强 《中山大学学报(医学版)》 CAS CSCD 北大核心 2018年第5期660-668,共9页
【目的】研究一种在哺乳动物细胞中高效的基因敲入方法,比较带有oriP-EBNA1序列的episomal CRISPR/Cas9载体与普通CRISPR/Cas9载体的基因敲入效率是否有差别。【方法】首先利用慢病毒载体构建稳定表达红色荧光蛋白DsRedE2的人胚肾细胞系... 【目的】研究一种在哺乳动物细胞中高效的基因敲入方法,比较带有oriP-EBNA1序列的episomal CRISPR/Cas9载体与普通CRISPR/Cas9载体的基因敲入效率是否有差别。【方法】首先利用慢病毒载体构建稳定表达红色荧光蛋白DsRedE2的人胚肾细胞系(293FT)与人诱导多能干细胞系(hiPS);利用CRISPR/Cas9序列设计网站,设计和合成靶向DsRedE2的向导RNA(sgRNA),分别克隆至带有oriP-EBNA1的episomal CRISPR/Cas9敲除载体与普通CRISPR/Cas9敲除载体中,测序筛选插入正确片段的克隆;然后设计靶向DsRedE2的同源臂,把同源臂连接在绿色荧光蛋白(GFP)的两端,构建GFP敲入片段的载体。把两种敲除载体分别导入到DsRedE2-293FT与DsRedE2-hiPS细胞系中,在不同时间点通过荧光显微镜观察以及流式细胞分析比较细胞的敲除效率,同时利用PCR检测靶基因的敲除情况;在筛选获得有效的sgRNA片段后,把两种敲除载体和同源臂同时导入到DsRedE2-293FT与DsRedE2-hiPS细胞系中,在不同时间通过荧光显微镜观察以及流式细胞分析比较细胞的敲入效率,同时利用PCR检测DsRedE2序列中GFP的敲入情况。【结果】成功构建表达DsRedE2的293FT与hiPS细胞系;获得靶向DsRedE2的episomal CRISPR/Cas9敲除载体、普通CRISPR/Cas9敲除载体及带有GFP的同源臂载体;荧光显微镜观察与流式细胞分析结果显示,转染两种CRISPR/Cas9质粒均可以使DsRedE2阳性细胞明显减少,而且episomal CRISPR/Cas9质粒组的DsRedE2阳性细胞数量显著低于转染普通CRISPR/Cas9质粒组。同时,敲入实验证实episomal CRISPR/Cas9组的GFP阳性细胞数量比普通CRISPR/Cas9组更多;TA克隆测序证实打靶位点有敲除与敲入片段。【结论】episomal CRISPR/Cas9载体与普通CRISPR/Cas9载体在细胞上都能实现基因的敲除与敲入;带有oriP-EBNA1序列的episomal CRISPR/Cas9载体敲除和敲入的效率均比普通CRISPR/Cas9载体高。以上结果为利用episomal CRISPR/Cas9载体进行人多能干细胞的基因敲入研究和谱系追踪动物模型的建立提供了重要的实验基础。 展开更多
关键词 CRISPR/Cas9 episomal载体 敲除 敲入
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Impact of Different Light Characteristics on the Growth and Lipid Content of Diatom Phaeodactylum tricornutum Transconjugant Strains
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作者 Nikunj Sharma Elisa Ines Fantino +4 位作者 Fatima Awwad Natacha Mérindol Arun Augustine Fatma Meddeb Isabel Desgagné-Penix 《American Journal of Plant Sciences》 CAS 2023年第1期41-63,共23页
Light regulates important metabolic processes in microalgal cells, which can further impact the metabolism and the accumulation of biomolecules such as lipids, carbohydrates, and proteins. Different characteristics of... Light regulates important metabolic processes in microalgal cells, which can further impact the metabolism and the accumulation of biomolecules such as lipids, carbohydrates, and proteins. Different characteristics of light have been studied on various strains of the model diatom Phaeodactylum tricornutum, but not on transconjugant cells and information on wild-type strains is still limited. Therefore, we studied the impact of different light characteristics such as spectral quality, light intensity and light shift on the growth, and the composition in lipids and fatty acids of P. tricornutum cells to provide a comprehensive context for future applications. Initially, we tested the impact of spectral quality and light intensity on P. tricornutum transformed with an episomal vector (Ptev), harboring the resistance gene Sh ble. Results indicated that Ptev cells accumulated more biomass and overall lipids in spectral quality Red 1 (R1: 34% > 600 nm > 66%) more effectively as compared to Red 2 (R2: 8% > 600 nm > 92%). It was also detected that cell granularity was higher in R1 as compared to R2. Furthermore, by testing two light intensities 65 μmol&middot;m<sup>-2</sup>&middot;s<sup>-1</sup> and 145 μmol&middot;m<sup>-2</sup>&middot;s<sup>-1</sup> light, it was observed that 145 μmol&middot;m<sup>-2</sup>&middot;s<sup>-1</sup> led to an increase in growth trend, total biomass and lipid content. Combining spectral qualities and light intensities, we show that the lipid accumulation raised by 2.8-fold. Studying the light intensity and spectral quality allowed us to optimize the light conditions to R1 spectral quality and light intensity 145 μmol&middot;m<sup>-2</sup>&middot;s<sup>-1</sup>. These initial results showed that red light R1 at 145 μmol&middot;m<sup>-2</sup>&middot;s<sup>-1</sup> was the best condition for biomass and total lipids accumulation in Ptev cells. Next, we further combined these two-light optimizations with a third light characteristics, i.e. light shift, where the cultures were shifted during the early stationary phase to a different light environment. We studied Red light shift (Rs) to investigate how light condition variations impacted P. tricornutum transconjugants Ptev and with an episomal vector containing the reporter gene YFP (PtYFP). We observed that Rs induced growth and fatty acid eicosapentaenoic acid (EPA) in Ptev as compared to PtYFP. Altogether, the study shows that red light shift of R1 at 145 μmol&middot;m<sup>-2</sup>&middot;s<sup>-1</sup> promoted biomass and total lipids accumulation in Ptev and PtYFP cells. The study provides a comprehensive approach to using different light characteristics with the aim to optimize growth and lipids, as well as to fatty acid production. 展开更多
关键词 Phaeodactylum tricornutum Light Condition episomal Vector Dia-toms Fatty Acids Biomass
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建立非基因整合原发性骨髓纤维化诱导性多能干细胞株 被引量:1
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作者 许静 盛梦瑶 +10 位作者 周圆 邢文 白洁 温伟 纪光臻 张鸿雁 金晖 吕翠翠 袁卫平 张孝兵 程涛 《中国实验血液学杂志》 CAS CSCD 北大核心 2015年第5期1415-1421,共7页
目的:利用诱导多能性干细胞(iPSC)技术建立原发性骨髓纤维化(PMF)诱导多能性干细胞系,为研究血液病的发生发展提供一个实验模型。方法:采用非基因整合型质粒重编程携带JAK2V617F突变的PMF患者骨髓来源的单个核细胞,诱导生成该患者特异的... 目的:利用诱导多能性干细胞(iPSC)技术建立原发性骨髓纤维化(PMF)诱导多能性干细胞系,为研究血液病的发生发展提供一个实验模型。方法:采用非基因整合型质粒重编程携带JAK2V617F突变的PMF患者骨髓来源的单个核细胞,诱导生成该患者特异的iPS细胞株。结果:采用此方法建立的iPS细胞株,在体外能够稳定传代,无外源性基因整合,多能性基因表达水平与人胚胎干细胞类似,在体内具有形成三胚层结构的能力。测序结果显示,所建立的患者的iPS细胞株携带不同负荷的JAK2V617F突变。结论:成功地建立非基因整合的PMF患者特异的iPS细胞株,这为研究PMF的发病机制、化疗药物筛选及实现精准化治疗提供了一个重要的疾病模型。 展开更多
关键词 诱导多能性干细胞 原发性骨髓纤维化 非整合 episomal载体
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BTB/POZ结构域蛋白GRP对热休克中hsp900α基因表达的增强作用 被引量:1
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作者 陈永军 莫志成 +3 位作者 张旌 张业 吴宁华 沈珝琲 《中国医学科学院学报》 CAS CSCD 北大核心 2004年第4期392-395,共4页
目的 探讨人BTB/POZ结构域GAGA元件结合相关蛋白(GRP)在hsp90α基因表达中的作用。方法 用正义或反义GRP真核表达质粒或空载体,分别与装有hsp90α基因启动子(-1756-+37)的pREP4 episomalvector质粒和对照质粒pMCAT共转染Jurkat细胞,提取... 目的 探讨人BTB/POZ结构域GAGA元件结合相关蛋白(GRP)在hsp90α基因表达中的作用。方法 用正义或反义GRP真核表达质粒或空载体,分别与装有hsp90α基因启动子(-1756-+37)的pREP4 episomalvector质粒和对照质粒pMCAT共转染Jurkat细胞,提取总RNA,用竞争性半定量RT-PCR测定hsp90α-氯霉素乙酰基转移酶(CAT)报告基因相对启动子活性。结果 热休克时,GRP明显促进pREP4 episomal vector质粒上hsp90α-CAT报告基因启动子活性。结论 GRP可能通过参与染色质动态调整促进pREP4 episomal vector质粒上hsp900α CAT的表达。 展开更多
关键词 GAGA元件结合相关蛋白 pREP4 episomal VECTOR hsp90a
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非基因整合建立人诱导多能性干细胞方法的优化研究 被引量:1
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作者 刘淑平 李彦欣 +7 位作者 许静 顾海慧 张鸿雁 梁昊岳 刘汉芝 张孝兵 程涛 袁卫平 《中国实验血液学杂志》 CAS CSCD 北大核心 2014年第3期580-587,共8页
诱导多能性干细胞(iPSC)技术具有临床应用前景,但iPSC的遗传稳定性和成瘤性阻碍了其可能的临床应用。非整合质粒(Episomal)方法无外源基因整合到宿主基因组上并且方法简单,适宜推广,是目前保证iPSC遗传安全性的最佳方案之一,但其诱导效... 诱导多能性干细胞(iPSC)技术具有临床应用前景,但iPSC的遗传稳定性和成瘤性阻碍了其可能的临床应用。非整合质粒(Episomal)方法无外源基因整合到宿主基因组上并且方法简单,适宜推广,是目前保证iPSC遗传安全性的最佳方案之一,但其诱导效率偏低,严重阻碍了其应用。本研究旨在优化Episomal方法,将脐血单个核细胞(CB MNC)重编程为诱导多能性干细胞(iPSC),建立无基因整合的iPSC的高效生成技术体系,为以后建立疾病iPSC奠定基础。利用CB MNC,通过比较不同氧含量,诱导质粒,MNC培养方法和预刺激时间等条件对Episomal方法进行优化。结果表明:CB MNC采用红系培养液,培养8 d,使用启动子为SFFV(spleen focus forming virus)的Episomal载体,在低氧(3%)条件下诱导,CB MNC重编程效率最高,可达到0.12%。通过分析最佳条件下供体细胞成分发现,表型为CD36+CD71+CD235alow的有核红细胞是重编程最主要的供体细胞来源。结论:本研究成功建立并优化出一种可推广的高效安全的,可以用于临床应用研究的iPSC诱导技术。 展开更多
关键词 诱导多能性干细胞 脐血 单个核细胞 episomal载体 非整合
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Rock inhibitor may compromise human induced pluripotent stem cells for cardiac differentiation in 3D 被引量:1
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作者 Bin Jiang Wenquan Ou +6 位作者 James G.Shamul Hao Chen Sarah Van Belleghem Samantha Stewart Zhenguo Liu John P.Fisher Xiaoming He 《Bioactive Materials》 SCIE 2022年第3期508-522,共15页
Cardiomyocytes differentiated from human induced pluripotent stem cells(iPSCs)are valuable for the understanding/treatment of the deadly heart diseases and their drug screening.However,the very much needed homogeneous... Cardiomyocytes differentiated from human induced pluripotent stem cells(iPSCs)are valuable for the understanding/treatment of the deadly heart diseases and their drug screening.However,the very much needed homogeneous 3D cardiac differentiation of human iPSCs is still challenging.Here,it is discovered surprisingly that Rock inhibitor(RI),used ubiquitously to improve the survival/yield of human iPSCs,induces early gastrulation-like change to human iPSCs in 3D culture and may cause their heterogeneous differentiation into all the three germ layers(i.e.,ectoderm,mesoderm,and endoderm)at the commonly used concentration(10μM).This greatly compromises the capacity of human iPSCs for homogeneous 3D cardiac differentiation.By reducing the RI to 1μM for 3D culture,the human iPSCs retain high pluripotency/quality in inner cell mass-like solid 3D spheroids.Consequently,the beating efficiency of 3D cardiac differentiation can be improved to more than 95%in~7 days(compared to less than~50%in 14 days for the 10μM RI condition).Furthermore,the outset beating time(OBT)of all resultant cardiac spheroids(CSs)is synchronized within only 1 day and they form a synchronously beating 3D construct after 5-day culture in gelatin methacrylol(GelMA)hydrogel,showing high homogeneity(in terms of the OBT)in functional maturity of the CSs.Moreover,the resultant cardiomyocytes are of high quality with key functional ultrastructures and highly responsive to cardiac drugs.These discoveries may greatly facilitate the utilization of human iPSCs for understanding and treating heart diseases. 展开更多
关键词 episomal IPSC CARDIOMYOCYTE SPHEROID GelMA
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Cryptic NUP214-ABL1 fusion with complex karyotype, episomes and intra-tumor genetic heterogeneity in a T-cell lymphoblastic lymphoma
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作者 Moneeb A.K Othman Beate Grygalewicz +3 位作者 Agnieszka Kołkowska-Lesniak Joana B.Melo Isabel M.Carreira Thomas Liehr 《Journal of Cancer Metastasis and Treatment》 CAS 2018年第1期597-605,共9页
T-lymphoblastic lymphoma(T-LBL)is a rare and aggressive form of non-Hodgkin’s lymphoma and little is known about their molecular background.However,complex karyotypes were already related to this group of malignancy ... T-lymphoblastic lymphoma(T-LBL)is a rare and aggressive form of non-Hodgkin’s lymphoma and little is known about their molecular background.However,complex karyotypes were already related to this group of malignancy and associated with poor outcome.Here,we describe a 17-year-old female being diagnosed with T-LBL and a normal karyotype after standard G-banding with trypsin-Giemsa(GTG)-banding.However,further analyses including high-resolution molecular approaches,array-comparative genomic hybridization(aCGH),multiplex ligation-dependent probe amplification,fluorescence in situ hybridization and multicolor chromosome banding revealed a cryptic complex karyotype,NUP214-ABL1 gene fusion,episomes and intra-tumor genetic heterogeneity.In addition,homozygous loss of CDKN2A,as well as amplification of oncogene TLX1(HOX11)were detected.Actually,NUP214-ABL1 fusion gene replicated autonomously in this case as episomes.Overall,highly amplification of NUP214-ABL1 fusion gene defines possibly a new subgroup of T-LBL patients which accordingly could benefit from treatment with tyrosine kinase inhibitors.As episomes are missed in standard karyotyping aCGH should be performed routinely in T-LBL to possibly detect more of such cases. 展开更多
关键词 T-cell lymphoblastic lymphoma NUP214-ABL1 fusion complex karyotype episomes intra-tumor genetic heterogeneity molecular cytogenetics array comparative genomic hybridization
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