| Non-radioactive in vitro PINK1 Kinase Assays Using Ubiquitin or Parkin as Substrate
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Author:
Date:
2016-10-05
[Abstract] This protocol describes the in vitro phosphorylation of ubiquitin and Parkin by the kinase PINK1 using recombinant proteins. Both substrates, ubiquitin and Parkin, are phosphorylated at the conserved serine 65 residue (pS65-ubiquitin and pS65-Parkin). The protocol also includes the use of monomeric and K48- and K63-linked poly-ubiquitin chains as alternative substrates. Although there are commercially available antibodies, we have not tested their performance in this assay since, but used validated antibodies from our laboratory. An alternative antibody-independent method, the use of phos-tag gels to detect pS65-ubiquitin and pS65-Parkin, is described in addition.
[摘要] 该协议描述了通过激酶PINK1使用重组蛋白的泛素和帕金蛋白的体外磷酸化。两种底物，泛素和帕金蛋白，在保守的丝氨酸65残基（pS65-泛素和pS65-帕金蛋白）上磷酸化。该方案还包括使用单体和K48和K63连接的聚泛素链作为替代底物。虽然有市售的抗体，我们没有测试他们在这个测定中的性能，因为，但使用我们实验室的验证抗体。另外描述了另一种抗体非依赖性方法，使用phos-标记凝胶检测pS65-泛素和pS65-帕金。
[背景] 在细胞中， PINK1是稳定和激活的线粒体膜去极化和其他形式的应力，导致线粒体损伤。活化的PINK1磷酸化泛素，其作为线粒体表面上胞质E3泛素连接酶Parkin的受体。 Parkin对PINK1的磷酸化是Parkin对线粒体底物的完全活性所必需的。活性pS65-Parkin的存在在前馈机制中扩增了作为线粒体标记的线粒体上的pS65-泛素的量。最终，受损的线粒体被自噬噬菌体衔接子识别，并将被蛋白酶体和自噬（mitophagy）降解。这种关键的线粒体质量控制通路促进线粒体的周转，并防止可导致细胞变性的功能障碍线粒体的积累。 PINK1或Parkin中的功能缺失突变与早发性帕金森病相关。
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| RAB21 Activity Assay Using GST-fused APPL1
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Author:
Date:
2016-02-20
[Abstract] The Rab family of small GTPases are essential regulators of membrane trafficking events. As with other small GTPase families, Rab GTPases cycle between an inactive GDP- bound state and an active GTP-bound state. Guanine nucleotide exchange factors (GEFs) promote Rab activation with the exchange of bound GDP for GTP, while GTPase-activating proteins (GAPs) regulate Rab inactivation with GTP hydrolysis. Numerous methods have been established to monitor the activation status of Rab GTPases. Of those, FRET-based methods are used to identify when and where a Rab GTPase is activated in cells. Unfortunately, the generation of such probes is complex, and only a limited number of Rabs have been probed this way. Biochemical purification of activated Rabs from cell or tissue extracts is easily ...
[摘要] 小GTP酶的Rab家族是膜运输事件的必要调节剂。与其他小GTP酶家族一样，Rab GTP酶在不活动的GDP结合状态和活性GTP结合状态之间循环。鸟嘌呤核苷酸交换因子（GEF）促进Rab激活与交换绑定GDP GTP，而GTPase激活蛋白（GAP）调节Rab失活与GTP水解。已经建立了许多方法来监测Rab GTPases的活化状态。其中，基于FRET的方法用于鉴定细胞中Rab GTPase在何时和何地被激活。不幸的是，这种探针的产生是复杂的，并且只有有限数量的Rab已经以这种方式探测。来自细胞或组织提取物的活化的Rabs的生物化学纯化通过使用已知的Rab效应结构域以下拉特定的GTP结合的Rab形式是容易实现的。虽然这种方法不是理想的详细的亚细胞定位，它可以提供Rab活动的时间分辨率。越来越多的特异性效应物的鉴定现在允许在特定条件下测试许多Rab GTP酶的活化水平。在这里，我们描述了一种亲和纯化方法使用GST融合APPL1（一种已知的RAB21效应）来测试哺乳动物细胞中的RAB21激活。该方法成功地用于测定RAB21激活状态下营养丰富与饥饿条件下的变化，并测试在此过程中MTMR13 RAB21 GEF的需求。
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| A Simple Method to Generate Gene Knockout Clones in Human Cells Using Transcription Activator-Like Effector Nuclease (TALEN)
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Author:
Date:
2015-07-20
[Abstract] Transcription activator-like effectors (TALEs) are naturally occurring proteins secreted by the plant pathogen, Xanthomonas, and fused to the Fok1 endonuclease to generate TALE nucleases (TALENs). TALEN pairs bind to specific DNA sequences initiating Fok1 dimerization and double-stand cleavage of DNA within the TALEN target site. This cleavage event triggers cellular repair mechanisms that result in insertions and/or deletions (indels), which enable gene knockout. The high specificity and efficiency of TALENs makes them important tools for genome editing. Here, we describe a method for the generation of single-cell clones with targeted gene knockout by TALEN using co-transfection and FACS with a fluorescent reporter. This protocol was designed to knockout cell death-inducing ...
[摘要] 转录激活子样效应器（TALE）是由植物病原体黄单胞菌分泌的天然存在的蛋白质，并且与Fok1内切核酸酶融合以产生TALE核酸酶（TALEN）。 TALEN对与特异性DNA序列结合，启动FAL1二聚化和在TALEN靶位点内双链切割DNA。 该切割事件触发导致插入和/或缺失（插入缺失）的细胞修复机制，其使得能够进行基因敲除。 TALEN的高特异性和高效性使其成为基因组编辑的重要工具。 在这里，我们描述了使用共转染和FACS与荧光报告基因通过TALEN产生具有靶向基因敲除的单细胞克隆的方法。 该方案设计为在Huh7.5细胞中敲除诱导细胞死亡的DFFA样效应子b，CIDEB; 然而，该协议可以应用于广泛的细胞类型和感兴趣的基因。
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