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Gel extraction kit

Company: QIAquick
Catalog#: 28704
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Reconstitution of Chromatin by Stepwise Salt Dialysis
Author:
Date:
2021-04-05
[Abstract]  

Chromatin, rather than plain DNA, is the natural substrate of the molecular machines that mediate DNA-directed processes in the nucleus. Chromatin can be reconstituted in vitro by using different methodologies. The salt dialysis method yields chromatin that consists of purified histones and DNA. This biochemically pure chromatin is well-suited for a wide range of applications. Here, we describe simple and straightforward protocols for the reconstitution of chromatin by stepwise salt dialysis and the analysis of the chromatin by the micrococcal nuclease (MNase) digestion assay. Chromatin that is reconstituted with this method can be used for efficient homology-directed repair (HDR)-mediated gene edited with the CRISPR-Cas9 system as well as for biochemical studies of chromatin dynamics and

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[摘要]  [摘要]染色质而不是普通的DNA是介导细胞核中DNA定向过程的分子机器的天然底物。染色质可以重新构建d体外b ÿ使用不同的方法。盐渗析法产生的染色质由纯化的组蛋白和DNA组成。这种生物化学纯的染色质非常适合广泛的应用。在这里,我们描述了通过逐步盐透析和通过微球菌核酸酶(MNase)消化测定法对染色质进行分析的染色质重构的简单明了的协议。该复原用该方法染色质,可用于高效同源定向修复(HDR)介导的基因编辑编 使用CRISPR-Cas9系统,以及用于染色质动力学和功能的生化研究。


[背景]真核细胞中的DNA被组织成染色质。因此,理想情况下,DNA定向过程的分析(例如复制,重组,修复和转录)将使用染色质模板而不是纯DNA进行(Kadonaga,2019)。为此,染色质可通过使用ATP依赖性或ATP依赖性方法在体外从纯化的成分中重建(有关综述,请参见Lusser和Kadonaga,2004年)。

在这里,我们描述了染色质重建的特定方法,该方法在我们利用CRISPR-Cas9系统对细胞进行HDR介导的基因编辑研究中采用了(Cruz-Becerra和Kadonaga,2020年)。在这项工作中,我们发现相对于普通的(裸)DNA供体模板,通过使用染色质供体模板可以增强精确的HDR介导的DNA插入。我们还将这种方法用于染色质的生化分析,包括高迁移性N组(HMGN)蛋白(Rattner等,2009),染色质动力学(Torigoe等,2013),前核小体(Fei)的表征。等人,2015年),以及核小体失稳因子(NDF)(F ...

Expression and Purification of Yeast-derived GPCR, Gα and Gβγ Subunits for Structural and Dynamic Studies
Author:
Date:
2021-02-20
[Abstract]  

In the last several years, as evidence of a surged number of GPCR-G complex structures, the expressions of GPCRs and G proteins for structural biology have achieved tremendous successes, mostly in insect and mammalian cell systems, resulting in more than 370 structures of over 70 GPCRs have been resolved. However, the challenge remains, particularly in the conformational transition and dynamics study area where a much higher quantity of the receptors and G proteins is required even in comparison to X-ray and cryo-EM (5 mg/ml, 3 μl/sample) when NMR spectroscopy (5 mg/ml, 250 μl /sample) is applied. As a result, the expression levels of the insect and mammalian systems are also difficult to meet this demand, not to mention the prohibitive cost of producing GPCRs and G proteins using

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[摘要]  [摘要]在过去的几年中,作为GPCR-G复杂结构数量激增的证据,用于结构生物学的GPCR和G蛋白的表达已取得了巨大的成功,主要是在昆虫和哺乳动物细胞系统中,导致了370多个已解决了70多个GPCR的结构。但是,挑战仍然存在,特别是在构象转变和动力学研究领域,即使与X射线和冷冻EM相比(5 mg / ml,3μl /样品),也需要大量的受体和G蛋白。当应用NMR光谱法(5 mg / ml,250μl /样品)时。结果,i的表达水平 nsect和哺乳动物系统也很难满足这一需求,更不用说使用绝大多数系统使用这些系统生产GPCR和G蛋白的成本高昂了。因此,需要探索一种具有广泛适用性的有效,负担得起的实用方法。毕赤酵母表达系统已在GPCR制备中显示出其希望,并具有其他真核表达系统无法比拟的许多优点。在该系统中表达的GPCR价格便宜,易于操作,并且能够进行同位素标记。在此,我们提出最近开发并在我们的实验室升级的相关协议,包括表达和纯化的毕赤酵母衍生GPCR以G沿α和G βγ蛋白。我们预期这些协议将促进GPCR及其复合物的构象转变和动力学研究。


[背景] G蛋白偶联受体(GPCR)是最大的膜蛋白家族,在许多(病理)生理活动中起着关键作用。GPCR的或它们的效应物的功能障碍会导致各种病症,包括神经变性疾病,癌症,和慢性炎症(Overington等人,2006) ...

Multiplex T-cell Stimulation Assay Utilizing a T-cell Activation Reporter-based Detection System
Author:
Date:
2021-01-20
[Abstract]  

Immune tolerance and response are both largely driven by the interactions between the major histocompatibility complex (MHC) expressed by antigen presenting cells (APCs), T-cell receptors (TCRs) on T-cells, and their cognate antigens. Disordered interactions cause the pathogenesis of autoimmune diseases such as type 1 diabetes. Therefore, the identification of antigenic epitopes of autoreactive T-cells leads to important advances in therapeutics and biomarkers. Next-generation sequencing methods allow for the rapid identification of thousands of TCR clonotypes from single T-cells, and thus there is a need to determine cognate antigens for identified TCRs. This protocol describes a reporter system of T-cell activation where the fluorescent reporter protein ZsGreen-1 is driven by nuclear

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[摘要]  [摘要] 免疫耐受和应答都很大程度上由抗原呈递细胞(APC)表达的主要组织相容性复合物(MHC),T细胞上的T细胞受体(TCR)及其同源抗原之间的相互作用驱动。相互作用障碍导致自身免疫性疾病(例如1型糖尿病)的发病机理。因此,鉴定自身反应性T细胞的抗原表位导致治疗和生物标志物的重要进展。下一代测序方法可从单个T细胞快速鉴定数千种TCR克隆型,因此需要确定已鉴定TCR的同源抗原。该协议描述了T细胞活化的报告系统,其中荧光报告蛋白ZsGreen-1由活化T细胞的核因子(NFAT)信号驱动并通过流式细胞仪读取。记者T细胞也组成性表达额外的一对荧光素tein作为识别物,允许同时多路复用多达8种不同的报告T细胞系,每种表达不同的目标TCR,可通过流式细胞仪区分。一旦制成TCR表达细胞系,仅需一个转导步骤即可将其无限期用于制备新的T细胞系。这种多路复用系统允许筛选TCR-抗原相互作用的数量,否则这些相互作用将是不切实际的,可在多种情况下使用(即,筛选单个抗原或抗原库),并可用于研究任何T细胞-MHC-抗原三分子相互作用。

[背景] T细胞,抗原呈递细胞(APC)及其同源抗原之间的相互作用是自身免疫性疾病(例如1型糖尿病)的主要事件(Michels等,2017; ...

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