| Production, Purification and Characterization of Recombinant Biotinylated Phytochrome B for Extracellular Optogenetics
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Author:
Date:
2020-03-05
[Abstract] In the field of extracellular optogenetics, photoreceptors are applied outside of cells to obtain systems with a desired functionality. Among the diverse applied photoreceptors, phytochromes are the only ones that can be actively and reversibly switched between the active and inactive photostate by the illumination with cell-compatible red and far-red light. In this protocol, we describe the production of a biotinylated variant of the photosensory domain of A. thaliana phytochrome B (PhyB-AviTag) in E. coli with a single, optimized expression plasmid. We give detailed instructions for the purification of the protein by immobilized metal affinity chromatography and the characterization of the protein in terms of purity, biotinylation, spectral photoswitching and the ...
[摘要] [摘要 ] 在细胞外光遗传学领域，光感受器被应用于细胞外，以获得具有所需功能的系统。在各种应用的感光体中，植物色素是唯一可以通过与细胞相容的红色和远红外光照射而在活性和非活性光态之间主动和可逆地切换的色素。在此协议中，我们描述了在大肠杆菌中拟南芥光敏色素B（PhyB-AviTag ）的光敏域的生物素化变体的生产。 带有一个优化的表达质粒。我们给出了通过固定的金属亲和色谱法纯化蛋白质的详细说明，并根据纯度，生物素化，光谱光开关以及与它的相互作用伴侣PIF6的光依赖性相互作用对蛋白质进行了表征。与以前使用PhyB-AviTag 进行的研究相比，此方案中使用的优化表达质粒简化了生产过程，并显示出更高的产量和纯度。
[背景 ] 在新兴的细胞外光遗传学领域，光感受器被应用于细胞外，例如，以控制生物功能或设计光响应性生物材料（Leung 等，2008；Zhang 等，2015；Chen and Wegner ，2017 ; Lyu 等人，2017 ; Wang 等人，2017 ; Bartelt 等人，2018 ; Beyer 等人，2018a ; Beyer 等人，2018b ; Jia 等人，2018 ; Kolar 等人， 2018 ; Liu 等人，2018 ; Wu 等人，2018 ; Baaske 等人，2019 ; Gil 等人，2019 ; H?rner ...
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| Purifying Properly Folded Cysteine-rich, Zinc Finger Containing Recombinant Proteins for Structural Drug Targeting Studies: the CH1 Domain of p300 as a Case Example
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Author:
Date:
2017-09-05
[Abstract] The transcription factor Hypoxia-Inducible Factor (HIF) complexes with the coactivator p300, activating the hypoxia response pathway and allowing tumors to grow. The CH1 and CAD domains of each respective protein form the interface between p300 and HIF. Small molecule compounds are in development that target and inhibit HIF/p300 complex formation, with the goal of reducing tumor growth. High resolution NMR spectroscopy is necessary to study ligand interaction with p300-CH1, and purifying high quantities of properly folded p300-CH1 is needed for pursuing structural and biophysical studies. p300-CH1 has 3 zinc fingers and 9 cysteine residues, posing challenges associated with reagent compatibility and protein oxidation. A protocol has been developed to overcome such issues by incorporating ...
[摘要] 与共激活因子p300的转录因子缺氧诱导因子（HIF）复合物，激活缺氧反应途径并允许肿瘤生长。每个相应蛋白质的CH1和CAD结构域形成p300和HIF之间的界面。正在开发靶向和抑制HIF / p300复合物形成的小分子化合物，目的是减少肿瘤生长。研究配体与p300-CH1相互作用的高分辨NMR光谱是必要的，为了进行结构和生物物理学研究，需要净化大量正确折叠的p300-CH1。 p300-CH1具有3个锌指和9个半胱氨酸残基，构成与试剂相容性和蛋白氧化相关的挑战。已经开发了一种通过在表达过程中并入锌并简化纯化时间来克服这些问题的方案，导致适合于结构NMR研究的最佳折叠蛋白质（120mg / 4L表达介质）的高产率。已证实最终重组p300-CH1的结构完整性是使用一维1 H NMR光谱和圆二色性最优的。该方案适用于纯化其他含锌指蛋白质。
【背景】由于不适当的血管灌注，实体瘤的发展与缺氧区的发展有关。对于缺氧微环境，肿瘤细胞过表达低氧诱导因子（HIF），一种异二聚体转录因子家族（Semenza，2002; Brat和Van Meir，2004; Kaur等，2005）。 HIFs结合p300（一种转录共激活因子），形成诱导HIF靶基因的复合物，从而激活缺氧反应途径并促进肿瘤生长（Kasper and Brindle，2006; Liu，2008）。涉及HIF / p300蛋白 ...
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| Preparation of Recombinant Galectin-3 for Cancer Studies
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Author:
Date:
2016-01-05
[Abstract] Galectin-3 is a member of a class of proteins termed Galectins, characterized by their ability to bind glycans containing β-galactose (Cummings and Liu, 2009). Galectin-3 binds preferentially to proteoglycans terminating with N-acetyllactosamine (LacNAc) chains (i.e., tandem repeats of galactose) (Newlaczyl and Yu, 2011). Galectin-3 is unique among the galectins in its chimeric structure. It shares a conserved carbohydrate recognition domain (CRD) with the other galectins, but has a long amino-terminal tail that is thought to be involved in protein aggregation. It can also form homodimers through its CRD (Cummings and Liu, 2009). Galectin-3 has been found to have diverse functions in tumorigenesis including: signaling, apoptosis inhibition, immune suppression, cell growth, and ...
[摘要] Galectin-3是称为Galectins的一类蛋白质的成员，其特征在于它们结合含有β-半乳糖的聚糖的能力（Cummings和Liu，2009）。 Galectin-3优先结合以N-乙酰乳糖胺（LacNAc）链（即半乳糖的串联重复）终止的蛋白聚糖（Newlaczyl和Yu，2011）。 Galectin-3在其嵌合结构中的半乳凝素中是独一无二的。它与其他半乳凝素共享保守的碳水化合物识别结构域（CRD），但具有被认为参与蛋白质聚集的长氨基末端尾部。它也可以通过CRD形成同型二聚体（Cummings和Liu，2009）。已经发现Galectin-3在肿瘤发生中具有多种功能，包括：信号转导，凋亡抑制，免疫抑制，细胞生长和转移等。 ...
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