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核酸酶基因LoENDONUCLEASE1在东方百合花朵衰老过程中的功能分析 被引量:1
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作者 李蕊蕊 刘玉杰 +4 位作者 许鑫彤 刘熠 何颖姣 王彩云 罗靖 《华中农业大学学报》 CAS CSCD 北大核心 2024年第1期157-165,共9页
为明确百合(Lilium spp.)花朵衰老发生的分子机制,在东方百合‘西伯利亚’(Lilium oriental hybrid‘Siberia’)花被片中克隆了一个衰老相关基因LoENDONUCLEASE 1(SAG10),利用qRT-PCR进行基因表达分析,并通过农杆菌介导的拟南芥稳定表... 为明确百合(Lilium spp.)花朵衰老发生的分子机制,在东方百合‘西伯利亚’(Lilium oriental hybrid‘Siberia’)花被片中克隆了一个衰老相关基因LoENDONUCLEASE 1(SAG10),利用qRT-PCR进行基因表达分析,并通过农杆菌介导的拟南芥稳定表达系统和百合花被片瞬时表达体系验证LoENDONUCLEASE 1基因功能。结果显示,LoENDONUCLEASE 1基因开放阅读框(ORF)为921 bp,编码306个氨基酸;LoENDONU⁃CLEASE 1在百合花朵和叶片的衰老过程中特异表达,且受到脱落酸和水杨酸的诱导;拟南芥过表达LoENDO⁃NUCLEASE 1株系中叶片叶绿素含量显著低于对照株系,百合花被片中瞬时过表达LoENDONUCLEASE 1基因加速了百合花被片的衰老,且过表达花被片中丙二醛和离子渗透率含量显著高于对照。结果表明,LoEN⁃DONUCLEASE 1具有促进花朵和叶片衰老的功能。 展开更多
关键词 百合 鲜切花 花朵衰老 衰老相关基因 核酸酶 过表达
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Genome engineering and disease modeling via programmable nucleases for insulin gene therapy;promises of CRISPR/Cas9 technology 被引量:2
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作者 Yunus E Eksi Ahter D Sanlioglu +2 位作者 Bahar Akkaya Bilge Esin Ozturk Salih Sanlioglu 《World Journal of Stem Cells》 SCIE 2021年第6期485-502,共18页
Targeted genome editing is a continually evolving technology employing programmable nucleases to specifically change,insert,or remove a genomic sequence of interest.These advanced molecular tools include meganucleases... Targeted genome editing is a continually evolving technology employing programmable nucleases to specifically change,insert,or remove a genomic sequence of interest.These advanced molecular tools include meganucleases,zinc finger nucleases,transcription activator-like effector nucleases and RNA-guided engineered nucleases(RGENs),which create double-strand breaks at specific target sites in the genome,and repair DNA either by homologous recombination in the presence of donor DNA or via the error-prone non-homologous end-joining mechanism.A recently discovered group of RGENs known as CRISPR/Cas9 gene-editing systems allowed precise genome manipulation revealing a causal association between disease genotype and phenotype,without the need for the reengineering of the specific enzyme when targeting different sequences.CRISPR/Cas9 has been successfully employed as an ex vivo gene-editing tool in embryonic stem cells and patient-derived stem cells to understand pancreatic beta-cell development and function.RNA-guided nucleases also open the way for the generation of novel animal models for diabetes and allow testing the efficiency of various therapeutic approaches in diabetes,as summarized and exemplified in this manuscript. 展开更多
关键词 Programmable nucleases CRISPR/Cas9 Stem cells Disease modeling DIABETES Insulin gene therapy
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原核Argonaute的应用研究进展
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作者 王飞 李文强 +4 位作者 刘洋 王珑瑜 陈晚苹 崔佳凯 马立新 《华中农业大学学报》 CAS CSCD 北大核心 2024年第4期82-93,共12页
原核生物Argonautes(pAgos)是参与细胞防御外来DNA入侵的可编程核酸酶。在体外,pAgos可以结合小的单链核酸(ssDNA/ssRNA)向导来识别和切割互补DNA/RNA。在体内,pAgos优先靶向多拷贝遗传元件、噬菌体和质粒,从而抑制入侵核酸的扩增和噬... 原核生物Argonautes(pAgos)是参与细胞防御外来DNA入侵的可编程核酸酶。在体外,pAgos可以结合小的单链核酸(ssDNA/ssRNA)向导来识别和切割互补DNA/RNA。在体内,pAgos优先靶向多拷贝遗传元件、噬菌体和质粒,从而抑制入侵核酸的扩增和噬菌体感染。pAgos作为一类新兴的可编程核酸酶,比目前应用最为广泛的CRISPR-Cas系统更具灵活性,在生物技术方面展现出巨大的潜力。早期的研究聚焦于嗜热的pAgo,目前基于嗜热pAgos的主要应用包括分子诊断和体外DNA组装。为了推进基于Ago的体内生物技术,如基因编辑的应用,研究人员的焦点逐渐转移到中温生物来源的pAgos,虽然目前pAgos还未实现基因组编辑,但是随着越来越多的pAgo被发掘以及研究人员对pAgos催化机制的深入研究,有望开发基于pAgos的下一代基因编辑技术。本文总结了已知代表性pAgos和基于pAgos发展的生物技术,并简要分析了pAgos在原核生物和真核生物体内应用面临的挑战和可能的应对策略。 展开更多
关键词 可编程核酸酶 原核Argonaute 基因编辑 分子诊断 DNA组装
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核酸酶NucB高效表达工程菌株的构建及功能测定
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作者 李江勇 陈熙明 +4 位作者 刘光琇 张威 陈拓 袁亚玲 李善家 《兰州大学学报(医学版)》 2024年第2期12-17,共6页
目的构建可以高效稳定表达核酸酶NucB的工程菌株。方法以大肠杆菌DH5α(DE3)为材料,采用基因编辑的方法将其中的必需基因lexA敲除,重新设计一个带有lexA基因的质粒进行基因回补,从而得到工程菌株DH5α(DE3)ΔlexA,再将带有目的基因nucB... 目的构建可以高效稳定表达核酸酶NucB的工程菌株。方法以大肠杆菌DH5α(DE3)为材料,采用基因编辑的方法将其中的必需基因lexA敲除,重新设计一个带有lexA基因的质粒进行基因回补,从而得到工程菌株DH5α(DE3)ΔlexA,再将带有目的基因nucB的质粒转入基因改造后的菌株中发酵培养生产核酸酶NucB并测定功能。结果经过基因改造后的大肠杆菌DH5α(DE3)ΔlexA与未经基因改造的大肠杆菌对比显示:改造后的菌株质粒非常稳定,蛋白表达量高且发酵过程中可以不用添加抗生素来生产核酸酶NucB。结论以基因编辑的方法成功构建一株无抗生素、高效稳定表达核酸酶NucB的工程菌株DH5α(DE3)ΔlexA。 展开更多
关键词 基因敲除 无抗生素 高效稳定 核酸酶NucB
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微生物发酵法制备核酸酶P1及其性质和应用
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作者 胡洋 万吉林 +2 位作者 侯莎 吴昌正 童星 《中国调味品》 CAS 北大核心 2024年第10期216-220,共5页
核酸酶P1又名5′-磷酸二酯酶,是酶法制备5′-核苷酸的关键酶类。文章对核酸酶P1的结构、性质、发酵工艺及其在食品领域的应用进行了总结,并对其未来的发展方向进行了展望。
关键词 核酸酶P1 性质 发酵 固定化 应用
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固定化核酸酶的制备及其降解沼液中抗生素抗性基因sul 1的研究
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作者 蓝丽华 陈雨心 +2 位作者 张问鼎 王婷 张进 《环境污染与防治》 CAS CSCD 北大核心 2024年第10期1414-1420,1428,共8页
为了削减畜禽沼液中抗生素抗性基因,以壳聚糖微球为载体,戊二醛为交联剂,采用共价交联法将核酸酶固定到壳聚糖微球上,优化了固定化核酸酶的制备条件,并探究了固定化核酸酶对模拟废水和猪场沼液中磺胺类抗生素抗性基因sul 1的去除效应,... 为了削减畜禽沼液中抗生素抗性基因,以壳聚糖微球为载体,戊二醛为交联剂,采用共价交联法将核酸酶固定到壳聚糖微球上,优化了固定化核酸酶的制备条件,并探究了固定化核酸酶对模拟废水和猪场沼液中磺胺类抗生素抗性基因sul 1的去除效应,为畜禽沼液中抗生素抗性基因进行生物酶法降解提供了新思路。结果表明:1)核酸酶成功固定化在壳聚糖微球表面。最佳制备条件为壳聚糖质量分数4%、戊二醛体积分数2%、交联时间8 h、固定化时间10 h。2)固定化核酸酶在模拟废水中的处理效果极佳,适用pH为5.5~8.5,适用温度为4~37℃,对模拟废水中sul 1的去除率可达100%。重复使用5次后,去除率仍保持在80%以上。3)对猪场原沼液中sul 1的去除效果不及模拟废水。稀释沼液可以有效缓解对核酸酶的抑制,稀释5倍后,在处理温度37℃、处理时间80 min条件下,对沼液中sul 1的去除率最高可达72.2%,重复使用5次后保持44.5%的酶活力。 展开更多
关键词 核酸酶 固定化酶 壳聚糖 抗生素抗性基因 沼液
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阴离子交换树脂固定化核酸酶P1的研究
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作者 王天赐 徐康 +1 位作者 侯亚利 杨忠华 《生物加工过程》 CAS 2024年第1期33-41,共9页
5′-核苷酸及其衍生物因具有较高的营养保健价值和药用价值,市场需求不断增大。核酸酶P1是目前5′-核苷酸工业生产的关键酶,但游离酶存在难以重复利用、消耗量过大等缺点。为了解决上述问题,提高核酸酶的利用效率,笔者利用不同类型树脂... 5′-核苷酸及其衍生物因具有较高的营养保健价值和药用价值,市场需求不断增大。核酸酶P1是目前5′-核苷酸工业生产的关键酶,但游离酶存在难以重复利用、消耗量过大等缺点。为了解决上述问题,提高核酸酶的利用效率,笔者利用不同类型树脂对核酸酶P1进行固定化。以核酸酶P1的吸附量和固定化酶的酶活为评价标准,研究发现阴离子交换树脂1(AER1)固定化时效果最佳,优化后的最佳固定化条件为酶量3 644.7 U/mL(2.2 mL)、戊二醛质量分数0.25%、交联时间1.5 h、固定化时间10.0 h、pH 5.1。该条件下制备的核酸酶P1的比酶活为47 980.95 U/g。在此最佳条件下,固定化酶的热稳定性有一定程度的提高;固定化酶的酸碱稳定性大幅度提高;固定化酶在4℃下保存6周后,酶活保留51.8%,是游离酶的1.6倍。 展开更多
关键词 核酸酶P1 树脂 固定化酶 交联
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葡萄球菌核酸酶样结构蛋白1/SLC7A11抑制铁死亡对骨肉瘤发生发展的影响
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作者 王胜涛 徐淑娟 +3 位作者 贵鹏 李欣咛 隋玉涵 李朝旭 《中国医学科学院学报》 CAS CSCD 北大核心 2024年第1期11-18,共8页
目的探讨葡萄球菌核酸酶样结构蛋白1(SND1)对骨肉瘤细胞生物学功能的影响,及其通过SLC7A11调控骨肉瘤细胞铁死亡的作用机制。方法检测人成骨细胞hFOB1.19以及骨肉瘤细胞系Saos-2、U2OS、HOS和143B中SND1的表达水平。采用小干扰RNA敲减... 目的探讨葡萄球菌核酸酶样结构蛋白1(SND1)对骨肉瘤细胞生物学功能的影响,及其通过SLC7A11调控骨肉瘤细胞铁死亡的作用机制。方法检测人成骨细胞hFOB1.19以及骨肉瘤细胞系Saos-2、U2OS、HOS和143B中SND1的表达水平。采用小干扰RNA敲减骨肉瘤细胞HOS和143B中SND1的表达(si-SND1),采用CCK8法、细胞克隆形成实验、细胞迁移和侵袭实验探究SND1的表达对骨肉瘤细胞生物学功能的影响;调控骨肉瘤细胞中SND1以及SLC7A11基因的表达,探究SND1通过SLC7A1基因对骨肉瘤铁死亡介导的肿瘤细胞凋亡的影响。结果骨肉瘤细胞Saos-2、U2OS、HOS和143B中SND1 mRNA和蛋白的表达水平显著高于人成骨细胞hFOB1.19(P均<0.01)。与对照组比较,si-SND1转染显著降低HOS和143B细胞中SND1的表达水平(P均<0.01),且细胞活性显著降低,克隆形成数量显著减少,细胞迁移和侵袭能力显著降低(P均<0.001)。铁死亡诱导剂Erastin促进骨肉瘤HOS和143B细胞凋亡,而抑制剂Ferrostatin-1刺激上调细胞活性(P均<0.001)。敲减SND-1后使用Erastin可进一步降低骨肉瘤HOS和143B细胞活性,而使用Ferrostatin-1刺激后可显著恢复细胞活性(P均<0.001);Erastin处理后,si-SND1组细胞中铁离子和丙二醛表达增高,谷胱甘肽表达降低(P均<0.001)。体内实验结果显示,敲减SND1可以明显抑制143B裸鼠移植瘤的瘤体质量(P<0.001)。敲减SND1后骨肉瘤HOS和143B细胞中SLC7A11的表达水平显著减少(P均<0.001),且铁死亡水平升高(P<0.001,P=0.020)。结论骨肉瘤细胞中SND1表达显著增高,其可能通过上调SLC7A11的表达抑制铁死亡,进而促进骨肉瘤细胞活性。 展开更多
关键词 骨肉瘤 葡萄球菌核酸酶样结构蛋白1 铁死亡
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基因编辑技术在免疫缺陷动物模型研究中的应用进展
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作者 马云辉 王晓堂 +1 位作者 高继萍 宋国华 《中国比较医学杂志》 CAS 北大核心 2024年第5期134-143,共10页
免疫缺陷动物模型在临床前研究中发挥重要作用,是现代生物医学研究领域的重要实验工具,广泛应用于免疫学、遗传学、肿瘤学与微生物学等研究领域。基因编辑是针对生物体基因组进行靶向修饰的技术,从出现到应用,极大推动了生物医学研究领... 免疫缺陷动物模型在临床前研究中发挥重要作用,是现代生物医学研究领域的重要实验工具,广泛应用于免疫学、遗传学、肿瘤学与微生物学等研究领域。基因编辑是针对生物体基因组进行靶向修饰的技术,从出现到应用,极大推动了生物医学研究领域的发展。基因编辑技术主要包括HEs、ZFNs、TALENs与CRISPR/Cas9系统。目前,研究者已利用该技术建立了多种类型的免疫缺陷动物模型,各有其优势和局限性。近年来,大量研究证实人源化免疫缺陷动物模型能够精准模拟癌细胞、药物以及免疫系统在人体内的作用,可以更好地模拟人类疾病,广泛用于研究人类免疫生物学及人类复杂疾病的潜在机制。本文对利用基因编辑技术构建免疫缺陷动物模型的研究应用进展进行综述,对基因编辑技术在免疫缺陷动物模型制备中存在的问题及优化策略深入探讨,并对其未来发展前景进行了展望,以期为研究者选用和建立免疫缺陷动物模型提供参考。 展开更多
关键词 免疫缺陷动物模型 基因编辑技术 锌指核酸酶 转录激活因子样效应核酸酶 CRISPR/Cas9
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Detection of Phaeocystis globosa using sandwich hybridization integrated with nuclease protection assay(NPA-SH) 被引量:11
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作者 Zhen Yu Mi Tiezhu Yu Zhigang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第12期1481-1486,共6页
Phaeocystis globosa Scherffel is one of the common harmful algae species in coastal waters of the southeastern China.In this study,sandwich hybridization integrated with nuclease protection assay(NPA-SH)was used to qu... Phaeocystis globosa Scherffel is one of the common harmful algae species in coastal waters of the southeastern China.In this study,sandwich hybridization integrated with nuclease protection assay(NPA-SH)was used to qualitatively and quantitatively detect P. globosa.Results showed that this method had good applicability and validity in analyzing the samples from laboratory cultures and from fields.The linear regression equation for P.globosa was obtained,and the lowest detection number of cells was 1.8×104 c... 展开更多
关键词 harmful algae blooms Phaeocystis globosa Scherffel sandwich hybridization integrated with nuclease protection assay (NPA-SH)
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Detection of Prorocentrum donghaiense using sandwich hybridization integrated with nuclease protection assay 被引量:2
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作者 CHEN Jie ZHEN Yu +1 位作者 MI Tiezhu YU Zhigang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2009年第2期121-126,共6页
Prorocentrum donghaiense is an important harmful algae bloom (HAB) causing creature in China's seas, and the conventional visual detection can not cope with long-term monitoring and highthroughput sampling projects... Prorocentrum donghaiense is an important harmful algae bloom (HAB) causing creature in China's seas, and the conventional visual detection can not cope with long-term monitoring and highthroughput sampling projects. An assay for P. donghaiense with sandwich hybridization integrated with nuclease protection assay (NPA-SH) was established. Tests with mixed samples and spiked field ones confirmed its good specificity and sensitivity. The cell number of P. donghaiense correlated well with the optical density, and the regression equation is y=4× 10^- 6x+ 0.694 9, in which x is the cell number, and y is the optical density, with r2=0.953 5. These results show that the NPA-SH method has good feasibility in the detection of P. donghaiense. Results of NPA-SH and microscopy are excellent for each sample. The NPA-SH method was a simple way in quantitative detection of P. donghaiense, and the whole process could be finished in about six hours, which provided a new approach in high-throughput sampling and long-term monitoring of P. donghaiense. 展开更多
关键词 Prorocentrum donghaiense ribosomal RNA S1 enzyme sandwich hybridization integrated with nuclease protection assay (NPA-SH)
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Preparation of human decellularized peripheral nerve allograft using amphoteric detergent and nuclease 被引量:2
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作者 Joo-Yul Bae Suk Young Park +2 位作者 Young Ho Shin Shin Woo Choi Jae Kwang Kim 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第9期1890-1896,共7页
Animal studies have shown that amphoteric detergent and nuclease(DNase I and ribonuclease A) is the most reliable decellularization method of the peripheral nerve. However, the optimal combination of chemical reagents... Animal studies have shown that amphoteric detergent and nuclease(DNase I and ribonuclease A) is the most reliable decellularization method of the peripheral nerve. However, the optimal combination of chemical reagents for decellularization of human nerve allograft needs further investigation. To find the optimal protocol to remove the immunogenic cellular components of the nerve tissue and preserve the basal lamina and extracellular matrix and whether the optimal protocol can be applied to larger-diameter human peripheral nerves, in this study, we decellularized the median and sural nerves from the cadavers with two different methods: nonionic and anionic detergents(Triton X-100 and sodium deoxycholate) and amphoteric detergent and nuclease(3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate(CHAPS), deoxyribonuclease I, and ribonuclease A). All cellular components were successfully removed from the median and sural nerves by amphoteric detergent and nuclease. Not all cellular components were removed from the median nerve by nonionic and anionic detergent. Both median and sural nerves treated with amphoteric detergent and nuclease maintained a completely intact extracellular matrix. Treatment with nonionic and anionic detergent decreased collagen content in both median and sural nerves, while the amphoteric detergent and nuclease treatment did not reduce collagen content. In addition, a contact cytotoxicity assay revealed that the nerves decellularized by amphoteric detergent and nuclease was biocompatible. Strength failure testing demonstrated that the biomechanical properties of nerves decellularized with amphoteric detergent and nuclease were comparable to those of fresh controls. Decellularization with amphoteric detergent and nuclease better remove cellular components and better preserve extracellular matrix than decellularization with nonionic and anionic detergents, even in large-diameter human peripheral nerves. In Korea, cadaveric studies are not yet legally subject to Institutional Review Board review. 展开更多
关键词 median nerve sural nerve nucleasE DETERGENT human decellularized nerve graft
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Ultrafast solvation dynamics at internal sites of staphylococcal nuclease investigated by site-directed mutagenesis
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作者 高光宇 李渝 +3 位作者 王伟 王树峰 Dongping Zhong 龚旗煌 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期81-88,共8页
Internal solvation of protein was studied by site-directed mutagenesis, with which an intrinsically fluorescent probe,tryptophan, is inserted into the desired position inside a protein molecule for ultrafast spectrosc... Internal solvation of protein was studied by site-directed mutagenesis, with which an intrinsically fluorescent probe,tryptophan, is inserted into the desired position inside a protein molecule for ultrafast spectroscopic study. Here we review this unique method for protein dynamics research. We first introduce the frontiers of protein solvation, site-directed mutagenesis, protein stability and characteristics, and the spectroscopic methods. Then we present time-resolved spectroscopic dynamics of solvation dynamics inside cavities of active sites. The studies are carried out on a globular protein, staphylococcal nuclease. The solvation at sites inside the protein molecule's cavities clearly reveals characteristics of the local environment. These solvation behaviors are directly correlated to enzyme activity. 展开更多
关键词 ultrafast spectroscopy protein dynamics staphylococcal nuclease(SNase) site-directed mutagenesis
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The Distribution and Substrate Specificity of Extracellular Nuclease Activity in Marine Fungi
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作者 Larissa A. Balabanova Michael V. Pivkin Valery A. Rasskazov 《Open Journal of Marine Science》 2012年第4期188-195,共8页
The distribution and specificity of extracellular nucleases produced by marine fungi belonging to eleven genera, namely: Alternaria, Aspergillus, Aureobasidium, Chaetomium, Fusarium, Gliomastix, Humicola, Penicillium,... The distribution and specificity of extracellular nucleases produced by marine fungi belonging to eleven genera, namely: Alternaria, Aspergillus, Aureobasidium, Chaetomium, Fusarium, Gliomastix, Humicola, Penicillium, Scopulariopsis, Wardomyces, Periconia, have implied its important function in the organic phosphorus and nitrogen circle in the Ocean. The fungal nucleases of 64 isolates tested were more or less specific for single-stranded DNA with a high preferential specificity towards poly-U substrate with forming of 5’-phosphate mononucleotides. A couple of the nucleases were capable of RNA digesting. The highest level of extracellular nucleolytic ability was observed in Penicillium spp. isolates. The tight correlation found between extracellular nuclease activity and the rate of thymidine uptake by actively growing and sporulating marine fungus Penicillium melinii suggests that this nuclease is required for fulfilling the nucleotide pool of precursors of DNA biosynthesis during transformation of hyphae into the aerial mycelium and conidia in stressful environmental conditions. 展开更多
关键词 MARINE Fungi MARINE Environment Single-Strand-Specific nucleasE DNASE RNAse SSDNA THYMIDINE Uptake
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Quantitation of DNA by nuclease P1 digestion and UPLC-MS/MS to assess binding efficiency of pyrrolobenzodiazepine
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作者 Yong Ma Buyun Chen Donglu Zhang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2020年第3期247-252,共6页
Accurate DNA quantitation is a prerequisite in many biomedical and pharmaceutical studies.Here we established a new DNA quantitation method by nuclease P1 digestion and UPLC-MS/MS analysis.DNA fragments can be efficie... Accurate DNA quantitation is a prerequisite in many biomedical and pharmaceutical studies.Here we established a new DNA quantitation method by nuclease P1 digestion and UPLC-MS/MS analysis.DNA fragments can be efficiently hydrolyzed to single deoxyribonucleotides by nuclease P1 in a short time.The decent stabilities of all the four deoxyribonucleotides were confirmed under different conditions.Deoxyadenosine monophosphate(dAMP)was selected as the surrogate for DNA quantitation because dAMP showed the highest sensitivity among the four deoxyribonucleotides in the UPLC-MS/MS analysis.The linear range in DNA quantitation by this method is 1.2-5000 ng/mL.In the validation,the inter-day and intra-day accuracies were within 90%-110%,and the inter-day and intra-day precision were acceptable(RSD<10%).The validated method was successfully applied to quantitate DNA isolated from tumors and organs of a mouse xenograft model.Compared to the quantitation methods using UV absorbance,the reported method provides an enhanced sensitivity,and it allows for the accurate quantitation of isolated DNA with contamination of RNA and ribonucleotide. 展开更多
关键词 nuclease P1 UPLC-MS/MS DNA quantitation DNA alkylation Pyrrolobenzodiazepine(PBD-Dimer)
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Integration of the nuclease protection assay with sandwich hybridization (NPA-SH) for sensitive detection of Heterocapsa triquetra
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作者 PARK Mirye PARK So Yun +4 位作者 HWANG Jinik JUNG Seung Won 3LEE Juyun CHANG Man LEE Taek-Kyun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第5期107-112,共6页
Microalgae are photosynthetic microorganisms that function as primary producers in aquatic ecosystems. Some species of microalgae undergo rapid growth and cause harmful blooms in marine ecosystems. Heterocapsa triquet... Microalgae are photosynthetic microorganisms that function as primary producers in aquatic ecosystems. Some species of microalgae undergo rapid growth and cause harmful blooms in marine ecosystems. Heterocapsa triquetra is one of the most common bloom-forming species in estuarine and coastal waters worldwide. Although this species does not produce toxins, unlike some other Heterocapsa species, the high density of its blooms can cause significant ecological damage. We developed a H. triquetra species-specific nuclease protection assay sandwich hybridization(NPA-SH) probe that targets the large subunit of ribosomal RNA(LSU r RNA). We tested probe specificity and sensitivity with five other dinoflagellates that also cause red tides. Our assay detected H.triquetra at a concentration of 1.5×10^4 cells/m L, more sensitive than required for a red-tide guidance warning by the Korea Ministry of Oceans and Fisheries in 2015(3.0×10^4 cells/m L). We also used the NPA-SH assay to monitor H. triquetra in the Tongyeong region of the southern sea area of Korea during 2014. This method could detect H.triquetra cells within 3 h. Our assay is useful for monitoring H. triquetra under field conditions. 展开更多
关键词 nuclease protection assay sandwich hybridization Heterocapsa triquetra red tide monitoring
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Transcribed single nucleotide polymorphism: Ideal markers for detecting gene imprinting by 5' nuclease assay
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作者 朱冠山 万谟彬 +1 位作者 朱忠政 郑瑞英 《Journal of Medical Colleges of PLA(China)》 CAS 2002年第4期242-246,共5页
Objective: To establish a novel approach for quick and highly efficient verification of human gene imprinting. Methods: A pair of dye-labelled probes, 5' nuclease assay was combined with RT-PCR to determine the ge... Objective: To establish a novel approach for quick and highly efficient verification of human gene imprinting. Methods: A pair of dye-labelled probes, 5' nuclease assay was combined with RT-PCR to determine the genotype of a transcribed single nucleotide polymorphism (SNP) rs705(C>T) of a known imprinted gene, small nuclear ribonucleotide protein N (SNRPN), on both genomic DNA and cDNA of human lym-phoblast cell lines. Results: Allele discrimination showed a clear monoallelic expression pattern of SNRPN, which was confirmed by RT-PCR based restriction fragment length polymorphism (RFLPs). Pedigree analysis verified the paternal origin of expressed allele, which was in consistency with previous report. Conclusion: Transcribed SNP is an ideal marker for detecting gene imprinting by 5' nuclease assay. This approach also may be used to discover differential allele expression of non-imprinted genes, finding out gene cis-acting functional polymorphism. 展开更多
关键词 single nucleotide polymorphism genomic imprinting 5' nuclease assay
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Spectroscopic Characterization of Staphylococcal Nuclease Mutants with Tryptophan at Internal Sites
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作者 高光宇 李渝 +3 位作者 王伟 仲冬平 王树峰 龚旗煌 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第4期151-155,共5页
Tryptophan (Trp) is an intrinsic fluorescent probe for detecting the site-specified dynamics inside/outside protein. It is found that the Trp can easily be inserted in desired sites of protein, which affects the int... Tryptophan (Trp) is an intrinsic fluorescent probe for detecting the site-specified dynamics inside/outside protein. It is found that the Trp can easily be inserted in desired sites of protein, which affects the integrity of the overall structure. To evaluate this effect, we design thirteen double point mutants of staphylococcal nuclease, each of which has a single Trp residue planted at an internal site. The studies on Trp fluorescence, ANS-binding fluorescence, far- and near-UV CD spectra, and enzymatic activity are carried out. It is found that the mutation at the hydrophobic core of protein generates molten globular state conformation, which is a loose structure compared to their original compactness in wild type (WT). Its enzyme activity and surface hydrophobicity are also affected. The studies show that by proper site designing and external binding, Trp mutagenesis is a suitable method for carrying out the study on site specified dynamics of proteins. 展开更多
关键词 WT Spectroscopic Characterization of Staphylococcal nuclease Mutants with Tryptophan at Internal Sites ANS
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家蚕RNAi效率相关核酸酶基因对RNAi效率的影响 被引量:1
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作者 陈咏琪 尹延萍 +4 位作者 冯嘉伟 白新宇 李庆荣 钟仰进 杨婉莹 《昆虫学报》 CAS CSCD 北大核心 2023年第3期303-311,共9页
【目的】鳞翅目(Lepidoptera)昆虫消化系统存在的核酸酶是导致RNAi低效的主要原因之一,本研究旨在探索家蚕Bombyx mori RNAi效率相关核酸酶(RNAi efficiency-related nuclease, REase)BmREase对家蚕RNAi低效的影响。【方法】利用RT-PCR... 【目的】鳞翅目(Lepidoptera)昆虫消化系统存在的核酸酶是导致RNAi低效的主要原因之一,本研究旨在探索家蚕Bombyx mori RNAi效率相关核酸酶(RNAi efficiency-related nuclease, REase)BmREase对家蚕RNAi低效的影响。【方法】利用RT-PCR对家蚕BmREase cDNA全长序列进行同源克隆和生物信息学分析,并采用最大似然法进行系统发育分析;利用qRT-PCR检测BmREase在游走期家蚕不同组织(头、表皮、脂肪体、中肠、气管、马氏管和丝腺)中的特异性表达。通过向游走期家蚕注射BmREase,家蚕蜕皮激素受体(ecdysone receptor, EcR)基因BmEcR,超气门蛋白(ultraspiracle, USP)基因BmUSP和细胞因子sp?tzle1(BmSpz1)基因BmSpz1的dsRNA进行RNAi,分析干扰BmREase表达后是否可以提高靶基因dsRNAs的干扰效率。【结果】RT-PCR扩增得到家蚕BmREase(GenBank登录号:XM_021350017.2)全长cDNA序列,其ORF长2 241 bp,编码746个氨基酸残基;生物信息学分析发现,BmREase与人核酸外切酶I 3qe9.1具有极其相似的结构,其Thr7, His33, Ala37, Arg93, Lys97, Tyr159, Asp160, Ser161和Asn174组成的活性结构域能够与核苷酸序列结合,暗示BmREase具有核酸酶活性。qRT-PCR结果显示,BmREase在家蚕游走期的中肠和马氏管中高表达,说明BmREase主要在家蚕消化系统中表达。在家蚕游走期注射dsRNA,BmREase的表达量比空白对照组的高,RNAi干扰BmREase提高了dsBmEcR, dsBmUSP和dsBmSpz1的干扰效率。【结论】家蚕体内存在与人类核酸外切酶相似功能的酶BmREase,其存在可能影响dsRNA在家蚕体内的干扰效果。本研究为利用RNAi进行家蚕基因功能的研究以及进一步开发RNAi防治害虫具有指导性意义。 展开更多
关键词 家蚕 RNA干扰 DSRNA RNAi效率相关核酸酶 BmREase dsRNA外切酶
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核酸酶在酱油酿造上的应用研究 被引量:2
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作者 赵悦 丁婷婷 +2 位作者 张梦丽 冯怡华 王春玲 《中国调味品》 CAS 北大核心 2023年第8期6-11,共6页
该研究采用低盐固态酱油发酵工艺,采用单一菌株(米曲霉3.042)进行制曲,在制曲过程中添加核酸酶来实现酶法辅助发酵。采用单因素实验确定核酸酶的最佳添加量和添加时间。通过测定酱醅的总酸、氨基酸态氮等理化指标以及成品酱油中的风味成... 该研究采用低盐固态酱油发酵工艺,采用单一菌株(米曲霉3.042)进行制曲,在制曲过程中添加核酸酶来实现酶法辅助发酵。采用单因素实验确定核酸酶的最佳添加量和添加时间。通过测定酱醅的总酸、氨基酸态氮等理化指标以及成品酱油中的风味成分,最后进行成品酱油的感官评定,探讨外源核酸酶在酱油酿造中的作用。结果表明,核酸酶的最佳添加量为大曲质量的0.3%。同时核酸酶的添加提高了大曲的酶活,保证了原料中大分子物质的分解和有效利用,从而具有提高酱油原料利用率和改善酱油风味的效果。 展开更多
关键词 低盐固态酱油 核酸酶 酶活 理化特性 风味 感官评定
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