| Expression and Purification of Recombinant Skd3 (Human ClpB) Protein and Tobacco Etch Virus (TEV) Protease from Escherichia coli
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Author:
Date:
2020-12-05
[Abstract] Skd3 (encoded by human CLPB) is a mitochondrial AAA+ protein comprised of an N-terminal ankyrin-repeat domain and a C-terminal HCLR-clade nucleotide-binding domain. The function of Skd3 has long remained unknown due to challenges in purifying the protein to high quality and near homogeneity. Recently we described Skd3 as a human mitochondrial protein disaggregase that solubilizes proteins in the mitochondrial intermembrane space. This protocol overcomes the challenges associated with purifying Skd3 and allows for in depth in vitro study of Skd3 activity. Tobacco etch virus (TEV) protease is required in the purification of Skd3. Thus, we also describe how to purify high quality TEV protease for use in the purification of Skd3, other purification protocols, and in vitro assays requiring TEV ...
[摘要] [摘要] Skd3（由人类CLPB编码）是一种线粒体AAA +蛋白，由N末端锚蛋白重复域和C末端HCLR分支核苷酸结合域组成。由于在纯化蛋白质达到高质量和接近均质性方面的挑战，Skd3的功能长期未知。最近，我们描述Skd3作为人类线粒体蛋白disaggregase ，在线粒体膜间间隙增溶蛋白。该协议克服了与纯化Skd3相关的挑战，并允许对Skd3活性进行深入的体外研究。Skd3的纯化需要烟草蚀刻病毒（TEV）蛋白酶。因此，我们还描述了如何净化高质量TEV蛋白酶可用于纯化Skd3，其他纯化方案以及需要TEV蛋白酶的体外测定。
[背景] Skd3是一种线粒体AAA +蛋白，与多系统线粒体疾病VII型3-甲基谷氨酸酸尿症（MGCA7）有关（Capo-Chichi等人，2015； Kanabus等人，2015； Saunders等人，， 2015; Wortmann等人，2015 ; Kiykim等人，2016 ）。由于在体外研究Skd3的能力有限，因此对生物学功能和这些突变对Skd3活性的影响的研究仍难以捉摸（Cupo和Shorter，2020； ...
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| Accurate, Streamlined Analysis of mRNA Translation by Sucrose Gradient Fractionation
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Author:
Date:
2017-10-05
[Abstract] The efficiency with which proteins are produced from mRNA molecules can vary widely across transcripts, cell types, and cellular states. Methods that accurately assay the translational efficiency of mRNAs are critical to gaining a mechanistic understanding of post-transcriptional gene regulation. One way to measure translational efficiency is to determine the number of ribosomes associated with an mRNA molecule, normalized to the length of the coding sequence. The primary method for this analysis of individual mRNAs is sucrose gradient fractionation, which physically separates mRNAs based on the number of bound ribosomes. Here, we describe a streamlined protocol for accurate analysis of mRNA association with ribosomes. Compared to previous protocols, our method incorporates internal ...
[摘要] 从mRNA分子产生蛋白质的效率可以在转录本，细胞类型和细胞状态之间广泛变化。准确测定mRNA翻译效率的方法对获得对转录后基因调控的机理理解至关重要。测量翻译效率的一种方法是确定与mRNA分子相关的核糖体的数目，归一化为编码序列的长度。分析单个mRNA的主要方法是蔗糖梯度分级，其基于结合核糖体的数目物理分离mRNA。在这里，我们描述了精确分析与核糖体的mRNA相关性的简化方案。与以前的方案相比，我们的方法结合内部控制和改进的缓冲条件，共同减少由非特异性mRNA - 核糖体相互作用引起的伪像。此外，我们的直接分数qRT-PCR方案消除了从梯度部分中RNA纯化的需要，这大大减少了所需的手动时间量，并促进了多个条件或基因靶标的并行分析。此外，在该过程中不产生苯酚废物。我们最初开发了协议来研究S-HAC1 mRNA的翻译抑制状态。但是我们还详细介绍了哺乳动物细胞系和组织的适应程序。
【背景】将mRNA翻译成蛋白质是一种高度调节的过程，其可以以不同的速率发生，这取决于基因，细胞环境或环境。翻译起始，延伸和终止的每个步骤可以是最终影响与mRNA相关的核糖体数量的调节点（Dever和Green，2012; ...
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