specifically Protocols

Category: Bioinformatics

Using AFPredictor, it was demonstrated that ‘ordered surface carbons’ (OSCs) are a distinguishing feature of AFPs and, more specifically, their ice-binding surfaces. AFPredictor identified AFPs from within a large set of structures with greater than 99% specificity. Furthermore, it was used to identify a novel ice-binding protein by screening a library of homology modeled structures based on cDNA sequences obtained from cold-acclimated winter rye (Secale cereale). - [Read A Computational Screening protocol for Antifreeze/Ice-Structuring Proteins]

Category: Cytoskeleton Protocols: Actin Myosin Protocols

Phalloidin binds specifically to F-actin, and fluorescent-tagged phalloidin stains the actin skeleton in cells in a manner that is very close to the staining pattern seen using anti-actin antibody. - [Read Actin Staining in Fixed Yeast Cells Protocol]

Category: Chromatography Protocols: Affinity Chromatography Protocols

Recombinant protein or a chemically synthesized bioactive fragment is immobilized on resin and used as a probe to capture interacting proteins directly from a cell extract.  Affinity-purified proteins are fractionated by gel electrophoresis and visualized by Coomassie staining.  Proteins that interact specifically are identified by comparing this gel profile to one obtained from cell lysates passed over a control resin lacking the immobilized probe protein. - [Read Affinity Purification of Interacting Proteins from Cell Lysates Protocol]

Category: PCR Protocols: cDNA Synthesis Protocols

An oligodeoxynucleotide primer hybridized to mRNA is extended by an RNA-dependent DNA polymerase to create a cDNA copy that can be amplified by PCR.  Depending on the purpose of the experiment, the primer for first-strand cDNA synthesis can be specifically designed to hybridize to a particular target gene, or a general primer such as oligo(dT) can be used to prime cDNA synthesis from essentially all mammalian mRNAs - [Read Amplification of cDNA Generated by Reverse Transcription of mRNA Protocol]

Category: Antibody Protocols: Antibody Labeling Protocols

Once tissues are fixed and permeabilized, the antibodies are added. These antibodies can be labeled directly or detected by a labeled secondary reagent. For indirect detection, any reagent that binds specifically to the primary antibody can be "tagged" and used to locate the antibody. The possible reagents include anti-immunoglobulin antibodies, protein A or G, or, if the first antibody is labeled with biotin, streptavidin. They can be labeled with enzymes or gold. - [Read Binding Antibodies to Tissue Sections Protocol]

Category: Cell Organelle Protocols: Subcellular Fractionation Protocols: Peroxisome Isolation Protocols

Peroxisomes of higher eukaryotes, glycosomes of kinetoplastids, & glyoxysomes of plants are related microbody organelles that perform differing metabolic functions tailored to their cellular environments. The close evolutionary relationship of these organelles is most clearly evidenced by the conservation of proteins involved in matrix protein import and biogenesis. glycosome can be viewed as an offshoot of the peroxisomal lineage with additional metabolic functions, specifically glycolysi - [Read Biogenesis and Function of Peroxisomes and Glycosomes]

Category: Cell Biology and Cell Culture

OptiPrep Application sheet C14 describes procedures for determining the density and sedimenting properties of any cell (of any size or density) using either a continuous or discontinuous gradient of iodixanol. This Application Sheet describes procedures aimed at isolating specifically a relatively low-density cell fraction from any tissue. - [Read C25 Isolation from spleen, thymus, pancreas, alveolar tissue and other tissues]

Category: ELISA Protocols: Sandwich ELISA Assay Protocols

Cytokine sandwich ELISA are sensitive enzyme immunoassays that can specifically detect and quantitate the concentration of soluble cytokine and chemokine proteins. BD Biosciences - [Read Cytokine ELISA Protocol]

Category: Cell Biology and Cell Culture

Cell fractionation of cellular components using Percoll a synthetic, colloidal solution of polyvinylpyrrolidone coated silica, specifically designed for sedimentation centrifugation. Percoll becomes a simple matter to establish a linear density gradient. Organelle separations are much easier to accomplish on Percoll density gradients than on sucrose gradients. - [Read Equilibrium Density Gradient Percoll Protocol]

Category: Antibody Protocols: Antibody Production Protocols

Novel strategy of immunizing a phosphorylated peptide or a synthetic phosphopeptide, which corresponds to the protein phosphorylated at a targeted residue. Method has been applied to the production of antibodies that can specifically recognize the other types of site-specific protein modification, such as acetylation, methylation, and proteolysis. - [Read Functional Analyses for Site-Specific Phosphorylation of a Target Protein in Cells]

Category: Microarray Protocols: Microarray Hybridization Protocols

Protocol describes the direct detection of RNA on DNA microarrays using Hybrid Capture (HC) technology and the HC ExpressArray Kit developed by Diagene.  The kit uses a proprietary antibody that binds specifically to RNA:DNA hybrids and a second, fluorescently labeled, antibody that detects the primary antibody.  Total RNA is applied directly to a glass-spotted DNA microarray, and stable RNA:DNA hybrids are visualized via a Cy3-labeled secondary antibody. - [Read Hybridization and Detection Using the HC ExpressArray Kit Protocol]

Category: Immunology: Immunoprecipitation Protocols: Immunoprecipitation of Radiolabeled Cells Protocols

Coimmunoprecipitation is most commonly used to test whether two proteins of interest are associated in vivo, but it can also be used to identify novel interacting partners of a target protein. In both cases, the cells, which may have been labeled with [35S]methionine, are harvested and lysed under conditions that preserve protein-protein interactions. The target protein is specifically immunoprecipitated from the cell extracts, and the immunoprecipitates are fractionated by SDS-PAGE. - [Read Identification of Associated Proteins by Coimmunoprecipitation Protocol]

Category: Chromatography Protocols: Immobilized Metal Ion Affinity Chromatography Protocols

Protocol is specifically for the further enrichment of phosphopeptides from a phosphotyrosine pull-down.  This is the final step for the preparation and enrichment of phosphopeptides using immobilized metal affinity chromatography (IMAC) for the identification of the phosphopeptides by liquid chromatography tandem mass spectrometry (LC-MS/MS). - [Read Preparation and Enrichment of Phosphopeptides from Phosphotyrosine Protocol]

Category: Reporter Gene Assays: GFP Assay Protocols

Protocol specifically describes data acquisition for a particular variant of GFP (EGFP) or Oregon Green as a donor fluorophore, but it can be adapted for image acquisition of other chromophore. - [Read Probing Protein Interactions Using GFP and FRET]

Category: Primary Cell Isolation and Culture Protocols: Mammalian Cell Culture Protocols

Cryopreserved PBMCs are a common specimen source for studies of immunological responses to vaccines, immunotherapies, etc. The health and viability of cells recovered post-cryopreservation are of course critical to the success and accuracy of immunological assays performed on them. This protocol standardizes PBMC isolation and cryopreservation techniques, specifically for the assessment of thawed cells by cytokine flow cytometry. - [Read Protocol for Isolation, Cryopreservation, and Thawing of PBMCs]

Category: Cell Organelle Protocols: Subcellular Fractionation Protocols: Membrane Isolation Protocols

This protocol uses a "light mitochondrial" pellet from a mammalian liver homogenate. The gradient thus has to resolve a variety of denser components (peroxisomes, lysosomes, mitochondria) from the Golgi membranes, which have a low density in iodixanol (1.06-1.09 g/ml) [1]. The protocol is specifically tailored to the purification of Golgi membranes from this pellet and is unsuitable for the isolation or analysis of other organelles present in the light mitochondrial fraction. - [Read Purification of Golgi Membranes from a Light Mitochondrial Fraction in a Self-Generated Gradient]

Category: DNA Protein Interactions Protocols

The multiprotein-DNA complex of interest is formed using the site-specifically derivatized DNA fragment.  The complex is then UV-irradiated, initiating covalent cross-linking with proteins in direct physical proximity to the cross-linking agent.  Extensive nuclease digestion is performed to eliminate uncross-linked DNA and convert cross-linked DNA to a cross-linked, radiolabeled nucleotide "tag." - [Read Site-Specific Protein-DNA Photo-Cross-Linking: Analysis of Structural Organization of Protein-DNA]

Category: Pharmacology and Toxicology Protocols: Drug Discovery

Protocol describes a target selective S. aureus whole cell assay that combines agar-diffusion and protein over expression techniques.  This agar based two-plate differential sensitivity assay was used to help confirm the newly discovered antibiotic platensimycin inhibited bacterial growth by specifically targeting the essential FASII enzyme FabF6. - [Read Target Specific Whole Cell Assay for Antibacterial Drug Discovery Protocol]