type Protocols

Category: Cell Culture Protocols: Cell Immortalization Protocols

Cultivating animal cells in the laboratory is an indispensable technique for cell biologists. However, most normal primary cell lines, while faithfully reproducing the phenotype of their tissue of origin, do not grow indefinitely in culture. After a series of population doublings (the number of which varies by species, cell type, and culture conditions) primary cells enter a state where they no longer divide. - [Read Immortalization of Cells in Culture]

Category: Pharmacology and Toxicology Protocols: Cytotoxicity Protocols: Cell Specific Cytotoxicity Assays Protocols

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]

Category: Immunology: Mononuclear Cell Isolation Protocols

Presents two methods for preparing dendritic cells (DCs), a highly specialized type of antigen-presenting cell (APC). The first method involves the isolation of DCs from mouse spleen, resulting in a cell population that is highly enriched in accessory cell and APC function. A support protocol for collagenase digestion of splenocyte suspensions is described to increase the yield of dendritic cells. The second method involves generating large numbers of DCs from mouse bone marrow progenitor cells. - [Read Isolation of Dendritic Cells Protocol]

Category: Chromatography Protocols: Gas Chromatography Protocols

Linkage analysis provides information on sugar type, ring size, and substitution positions for each monosaccharide.  The method in this protocol, using NaOH as the base, is one of the simpler linkage analysis methods.  It requires approximately 1-5 µg of carbohydrate. - [Read Linkage Analysis Using the NaOH Methylation Method Protocol]

Category: Fungi Protocols: Neurospora Protocols

Protocols for Neurospora methods. Includes: Standard strains; Crosses; Minimal medium; Color coding of media; Agar substrate for manipulation and isolation; Stock solutions of supplements; Mating-type tests; Preservation of stocks by silica gel; Cleaning of glassware; Control of mites. - [Read Neurospora Methods Protocols]

Category: Cytoskeleton Protocols: Intermediate Filaments Protocols

Intermediate filaments (IF) are major cytoskeletal systems of vertebrate and many nonvertebrate cells whose expression is cell-type specific and developmentally regulated. This protocol describes the x-rhodamine labeling of one type of IF, vimentin, and a method for microinjection of the labeled vimentin into cultured cells. IF dynamics can then be examined with fluorescence microscopy. - [Read Preparation and Microinjection of x-Rhodamine-Labeled Vimentin Protocol]

Category: Microscopy Protocols: In Vivo Imaging Protocols

To image early cleavages and chromatin dynamics, it is convenient to use histone H2B fused to GFP or lamin::GFP. Time-lapse movies can be obtained using conventional confocal microscope systems and their included software. Early embryos dissected from transgenic hermaphrodites are placed with egg salts on agar pads. Chromatin dynamics can be followed easily, and wild-type embryonic cells can be compared with mutants or RNAi-treated embryos. - [Read Protocol Live Imaging of Caenorhabditis Elegans]

Category: Cytoskeleton Protocols: Intermediate Filaments Protocols

Intermediate filaments (IF) are major cytoskeletal systems of vertebrate and many nonvertebrate cells whose expression is cell-type specific and developmentally regulated. This protocol describes a method for purifying one type of IF, vimentin, from bovine lens tissue. Purification of human vimentin expressed in Escherichia coli is also described. These methods are useful in the preparation of other IF protein subunits for microinjection studies as well. - [Read Purification of Bovine Lens and Bacterially Expressed Human Vimentin Protocol]

Category: Viral Manipulation Protocols: M13 Phage Manipulation Protocols

Plaques formed by M13 bacteriophages or bacterial colonies transformed by plasmids carrying specific mutations can be detected by hybridization, using a radiolabeled oligonucleotide that forms a perfect duplex with the mutant sequence. Hybridization is carried out under conditions of low stringency that allow the radiolabeled oligonucleotide to anneal to both mutant and wild-type DNAs. - [Read Screening Recombinant Clones for Site-directed Mutagenesis by Hybridization to Radiolabeled Oligos]

Category: Chromatography Protocols: Ion Exchange Chromatography Protocols

Protocol for separating proteins using ion-exchange chromatography. Protocol details the practical considerations of an ion-exchange chromatography (IEC) experiment.  The choice of what type of ion exchanger to use, as well as the composition of the buffers used in this experiment, should be determined prior to beginning this protocol. - [Read Separating Proteins Using Ion-Exchange Chromatography Protocol]

Category: PCR Protocols: Colony PCR

The following colony PCR protocol has been designed to be performed in individual reaction tubes. We usually test three colonies from each transformation along with a wild-type control. A series of five different PCR tests are performed on each colony to - [Read Single tube confirmation PCR protocol]

Category: DNA Protocols: cDNA Library Protocols

Protocol describes the generation of cDNA probes from poly(A)+ mRNA using random oligonucleotide primers. Probes of this type are used for differential screening of cDNA libraries. - [Read Synthesis of cDNA Probes from mRNA Using Random Oligonucleotide Primers Protocol]

Category: Reporter Gene Assays: Luciferase Assay Protocols

Transfection of primary leukocytes has traditionally been a challenging but much desired protocol. It allows not only the analysis of cells in a more natural state to a cell line system, it enables the direct comparison of, for e.g. transcriptional activity using luciferase reporters, in immune cells taken from genetically-altered mice. In addition, importantly it allows for "rescue experiments" in knockout cells & the ability to over-express or reconstitute wild-type and/or mutated constructs. - [Read Transfection of Bone Marrow-Derived Mast Cells for Transcription Factor Luciferase Reporter Assays]

Category: Cell Biology and Cell Culture: Cell Transfection Protocol

Protocol optimized for Cos-1 cells. Successful transfection of each cell type requires optimization of the basic protocol. LIPOFECTAMINE method of transient transfection. Upstate. - [Read Transient Transfection of Cos-1 Cells]

Category: Protein Protocols: Immunoprecipitation Protocols: Immunoprecipitation Troubleshooting

Troubleshoot Immunoprecipitation. Chemicon. The most common challenge with immunoprecipitation is trying to lower the number and type of background proteins that contaminate the washed immune complexes. Suggestions for decreasing background in IP. - [Read Troubleshoot Immunoprecipitation]

Category: Protein Protocols: Western Blot Protocol: Troubleshooting Western Blots

Troubleshooting Guide for Chemiluminescent Western Blotting Pierce. High Background, Reverse image on film, Blot glows in the darkroom, Signal duration is less than 8 hours, Weak or no signal, Spots within the protein bands, non-specific bands. - [Read Troubleshooting Guide for Chemiluminescent Western Blotting Pierce]