Chemotaxis Assay, Springer Lab. A chemotaxis assay's function is to assess whether a factor or molecule of interest has chemotactic activity on a motile cell type. Chemotaxis is the ability of a factor to cause the migration of a cell. The chemotactic assay is based on the creation of a chemical gradient of the chemotactic agent which will cause cells to migrate through the gradient towards the chemotactic agent. - [Read Chemotaxis Assay]
Genome-wide location analysis, also known as ChIP-Chip, combines chromatin immunoprecipitation and DNA microarray analysis to identify protein-DNA interactions that occur in living cells. Protein-DNA interactions are captured in vivo by chemical crosslinking. Cell lysis, DNA fragmentation and immunoaffinity purification of the desired protein will co-purify DNA fragments that are associated with that protein. - [Read Chromatin Immunoprecipitation and Microarray-Based Analysis of Protein Location Protocol]
Electron Microscopy Protocols ... Chemical Fixation Protocol for Suspension-Cultured Plant Cells for TEM; Standard Glutaraldehyde Fixation for TEM of Animal ...Electron Microscopy Protocols. UBC BioImaging Facility - Bio-Rad Radiance Plus Confocal Microscope - Starting Up, page 1 - [Read Electron Microscopy Protocols]
Treating cells with paraformaldehyde leads to the establishment of chemical cross-links between free amino groups. When the cross-links join different molecules, a latticework of interactions occurs that holds the overall architecture of the cell together. Commercial formaldehyde solutions are not recommended, because they lack the advantages of using a variable-length polymer, and the cells will simultaneously be fixed with the alcohol (usually methanol). - [Read Fixing Attached Cells in Paraformaldehyde Protocol]
Treating cells with paraformaldehyde leads to the establishment of chemical cross-links between free amino groups. When the cross-links join different molecules, a latticework of interactions occurs that holds the overall architecture of the cell together. - [Read Fixing Suspension Cells with Paraformaldehyde Protocol]
New screening efforts and chemical modifications of existing compounds have been attempted to identify more selective and potent inhibitors. To determine the selectivity of the inhibitors identified during screening efforts we developed gel-elongation assay using crude bacterial lysate directly to determine the target specificities of fatty acid synthesis inhibitors. - [Read Gel-elongation Assay for Type II Fatty Acid Synthesis Protocol]
Accumulation of lipophilic substances in the plasma membrane may affect the membrane lipid order and consequently affect the function of these proteins. Changes in the activity of the Na+/K+ -ATPase, which is the major active transport system responsible for the electrochemical potential in mammalian cells, can therefore be an indication of the effect that a chemical may have on the viability of the cell membrane and possibly the whole cell. - [Read Hamster Ovary Cell NA+/K+ -ATPase Test]
Specific molecular components can be efficiently labeled by a combination of three methods: chemical transfection of GFP-fusion constructs, staining of chromosomes with the DNA-specific, fluorescent dye Hoechst 33342, and microinjection of fluorescently conjugated proteins. This procedure provides an example of using all three methods in sequence to label components of living HeLa cells. These methods should be followed in the order presented, but any of them can be omitted when not needed. - [Read Imaging Hoechst-Labeled Chromosomes and Fluorescent Proteins during the Cell Cycle]
Fluorescence microscopy provides a powerful tool for imaging molecular components in living cells. Specific molecular components can be efficiently labeled by a combination of three methods: chemical transfection of GFP-fusion constructs, staining of chromosomes with the DNA-specific, fluorescent dye Hoechst 33342, and microinjection of fluorescently conjugated proteins. This procedure provides an example of using all three methods in sequence to label components of living HeLa cells. - [Read Imaging Hoechst-Labeled Chromosomes and Fluorescent Proteins during the Cell Cycle]
The basis of this procedure is that two specific cell type preparations may be isolated, exposed separately to various compounds over a range of concentrations, and the cytotoxicity of these determined. Parameters deemed indicative of a cytotoxic effect include a reduction in de novo protein synthesis and decreased glucose and fatty acid metabolism. A cytotoxic effect may indicate that a chemical is likely to be nephrotoxic in vivo. - [Read Isolated Rat Glomeruli and Proximal Tubules]
This protocol describes a simple chemical oxidation method for labeling antibodies with iodine. Iodide-125 (supplied as NaI) is oxidized to form iodine-125 (I2), which attacks tyrosyl and histidyl side chains. The iodinated antibodies are easily detected and quantitated using gamma counters or film. They are used primarily in immunoassays, but other techniques can be adapted conveniently to the iodine detection method. - [Read Labeling Antibodies with Iodine Protocol]
Laboratory Safety Manual. McGill EHS. Workplace Hazardous Materials Information System (WHMIS), Control of Chemical Hazards, Handling and Storage of Laboratory Chemicals, Fire Safety in the Laboratory, Hazardous Waste Disposal. - [Read Laboratory Safety Manual]
Ligation with GUS vector and Transformation. Chemical Transformation of E. coli. Ligation Procedure for LigaFastâ„¢ Rapid DNA Ligation System (Promega). B. Beason, Rice University. - [Read Ligation with GUS vector and Transformation]
The basis of this test is that a cytotoxic chemical (regardless of site or mechanism of action) will interfere with the normal motility of the protozoan, Tetrahymena thermophila, in culture. The degree of interference of motility as compared to control cultures, related to the concentration of the test compound, provides an indication of toxicity. - [Read Tetrahymena Thermophila Ocular Irritancy Test]
No cell culture problem is as universal as that of culture loss due to contamination. All cell culture laboratories and cell culture workers have experienced it. Culture contaminants may be biological or chemical, seen or unseen, destructive or seemingly benign, but in all cases they adversely affect
both the use of your cell cultures and the quality of your research. Contamination problems can be divided into three classes: Minor annoyances, Serious problems, Major catastrophes. - [Read Understanding and Managing Cell Culture Contamination Protocol]
Background and methods to study plant transport. Includes new methods to study protein trafficking in plant cells, includes: Identification of protein sorting pathways in non purified samples; Localization of organelle proteins by isotype tagging/isotype-coded affinity tag; Coupling of chemical genomics and proteomics; Top down mass spectrometry; Compartment-specific markers to aid in the purification of organelles. - [Read Understanding Protein Trafficking in Plant Cells Through Proteomics]
Histone H1 Kinase Activity Assay Protocol. This protocol describes assaying kinase activity of a putative kinase using Histone H1 as the substrate. Histone H1 is the canonical kinase substrate in this type of assay. Phosphorylation of Histone H1 is assessed by SDS-Polyacrylamide gel electrophoresis followed by autoradiography.
This protocol a protocol on how to generate transfected embryonic stem (ES) cell clones. The previous protocol in this series is the Protocol for Electroporation of ES cells. The next protocol in the series is the Protocol on Disaggregation, Expansion, and Freezing of Transfected ES Clones.
This protocol describes the electroporation of the BMH 81-17 mut S strain that is recommended for tranformation of the site directed mutagenesis of dsDNA (See Protocol on Site-Directed Mutagenesis on Double Stranded DNA). BMH 81-17 mut S are a mismatch repair defective (mut S) Escherichia coli strain. The probability that the two mutations will cosegregate during the first round of DNA replication is increased in this strain.