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    Separation of Thylakoid Protein Complexes with Two-dimensional Native-PAGE
    Authors:  Marjaana Rantala, Virpi Paakkarinen and Eva-Mari Aro, date: 07/05/2018, view: 236, Q&A: 0
    [Abstract] The hierarchical composition and interactions of the labile thylakoid protein complexes can be assessed by sequential 2D-native gel-electrophoresis system. Mild non-ionic detergent digitonin is used to solubilize labile protein super-and megacomplexes, which are then separated with first-dimension blue native polyacrylamide gel electrophoresis ...
    CRISPR-mediated Tagging with BirA Allows Proximity Labeling in Toxoplasma gondii
    Authors:  Shaojun Long, Kevin M. Brown and L. David Sibley, date: 03/20/2018, view: 1201, Q&A: 0
    [Abstract] Defining protein interaction networks can provide key insights into how protein complexes govern complex biological problems. Here we define a method for proximity based labeling using permissive biotin ligase to define protein networks in the intracellular parasite Toxoplasma gondii. When combined with CRISPR/Cas9 based tagging, this ...
    Detection of Protein Interactions in the Cytoplasm and Periplasm of Escherichia coli by Förster Resonance Energy Transfer
    Authors:  Nils Y. Meiresonne, Svetlana Alexeeva, René van der Ploeg and Tanneke den Blaauwen, date: 01/20/2018, view: 1347, Q&A: 0
    [Abstract] This protocol was developed to qualitatively and quantitatively detect protein-protein interactions in Escherichia coli by Förster Resonance Energy Transfer (FRET). The described assay allows for the previously impossible in vivo screening of periplasmic protein-protein interactions. In FRET, excitation of a donor fluorescent ...
    MicroScale Thermophoresis as a Tool to Study Protein-peptide Interactions in the Context of Large Eukaryotic Protein Complexes
    Authors:  Maximilian G. Plach, Klaus Grasser and Thomas Schubert, date: 12/05/2017, view: 2801, Q&A: 0
    [Abstract] Protein-peptide interactions are part of many physiological processes, for example, epigenetics where peptide regions of histone complexes are crucial for regulation of chromatin structure. Short peptides are often also used as alternatives to small molecule drugs to target protein complexes. Studying the interactions between proteins and peptides ...
    Bioluminescence Resonance Energy Transfer (BRET) Assay for Determination of Molecular Interactions in Living Cells
    [Abstract] The bioluminescence resonance energy transfer (BRET) assay can be used as an indicator of molecular approximation and/or interaction. A significant resonance energy transfer signal is generated when the acceptor, having the appropriate spectral overlap with the donor emission, is approximated with the donor. In the example provided, proteins ...
    Detection of Membrane Protein Interactions by Cell-based Tango Assays
    [Abstract] The Tango assay is a protein-protein interaction assay, in which a transcription factor (rTA) is fused to a membrane-bound protein via a linker that contains a cleavage site for TEV protease, whereas a soluble interaction partner is fused to TEV protease (Barnea et al., 2008). Association between the two interaction partners leads to an ...
    Streptavidin Bead Pulldown Assay to Determine Protein Homooligomerization
    [Abstract] Pulldown assay is a conventional method to determine protein-protein interactions in vitro. Expressing a protein of interest with two different tags allows testing whether both versions can be captured via one of the two tags as homooligomeric complex. This protocol is based on streptavidin bead capture of a biotinylated protein and ...
    γ-Secretase Epsilon-cleavage Assay
    [Abstract] γ-Secretase epsilon-cleavage assay is derived from the cell-based Tango assay (Kang et al., 2015), and is a fast and sensitive method to determine the initial cleavage of C99 by γ-secretase. In this protocol, we use HTL cells, which are HEK293 cells with a stably integrated luciferase reporter under the control of the bacterial tetO ...
    Preparation of Crude Synaptosomal Fractions from Mouse Brains and Spinal Cords
    Author:  Oliver Wirths, date: 08/05/2017, view: 2761, Q&A: 0
    [Abstract] The current protocol describes the preparation of crude synaptosomal fractions from mouse brain or spinal cord samples. In detail, a sequential protocol yielding crude synaptosomal and light membrane fractions is provided. This fast and easy method might be sufficient to assess the amount of synaptic proteins in down-steam applications like ...
    Biochemical Analysis of Caspase-8-dependent Proteolysis of IRF3 in Virus-infected Cells
    Authors:  Gayatri Subramanian, Karen Pan, Ritu Chakravarti and Saurabh Chattopadhyay, date: 11/20/2016, view: 3166, Q&A: 0
    [Abstract] Interferon regulatory factor 3 (IRF3) is a transcription factor, which is critical for the antiviral response against a wide range of viruses (Hiscott, 2007; Ikushima et al., 2013). It gets activated in virus-infected cells via Toll like receptors (TLRs), RIG-I (retinoic acid inducible gene 1) like receptors (RLRs), cyclic GMP-AMP ...