The assay for ß-galactosidase relies on the ability of the enzyme to catalyze the hydrolysis of ONPG (o-nitrophenyl-ß-D- galactopyranoside) to free o-nitrophenol, which absorbs light at 420 nm. In this protocol, extracts of cells transfected with a ß-galactosidase reporter plasmid are incubated with ONPG. - [Read Assay for ß-galactosidase in Extracts of Mammalian Cells]
In this protocol, cells transfected with a luciferase reporter plasmid are lysed in a detergent-containing buffer. Luciferase in the extract catalyzes an oxidation reaction in which D-luciferin is converted to oxyluciferin, with production of light at 556 nm that can be quantified in a luminometer. - [Read Assay for Luciferase in Extracts of Mammalian Cells Protocol]
Method describes how a crude extract is prepared, and the activity is normalized to the amount of protein assayed. This method is particularly suitable for comparing cells that are grown under very different conditions or that have different genetic backgrounds. - [Read Assay of ß-Galactosidase in Yeast: Assay of Crude Extracts]
Protocol describes how a crude extract is prepared, and the activity is normalized to the amount of protein assayed. This method is particularly suitable for comparing cells that are grown under very different conditions or that have different genetic backgrounds. - [Read Assay of ß-Galactosidase in Yeast: Assay of Crude Extracts Protocol]
There are two basic methods for the in vitro assay of B-galactosidase activity from yeast. They
differ mainly in the method of preparing the material for assay. Both methods are described with accompanying protocols. Method I: Assay of Crude Extracts includes: Yeast Cell Growth; Yeast Cell Harvest; B-gal assays; Bradford Assays. Method II: Permeabilized cell assay. - [Read Assay of β-Galactosidase in Yeast Protocol]
Cell Lysate Extracts. Great protocols for cell lysis preparation from a variety of cell types. There are numerous methods of cell stimulation and lysis. For a given protein, Upstate’s Laboratories determine the specific treatment upon initial testing of its products. It is important to select the correct cell line, stimulation procedure (if any), and lysis protocol. Upstate. - [Read Cell Lysate Extracts]
ChIP assay protocol with 2 steps: in vivo formaldehyde cross-linking of whole cells and protein-protein and protein-DNA interactions, followed by immunoprecipitation of protein-DNA complexes with specific antibodies from sonicated extracts. Breeden Lab - [Read Chromatin IP (CHIP assay)]
Cytostatic factor extract (CSF) preparation for spindle assembly protocol. Protocol includes tips such as: The quality of the eggs is essential for good CSF extracts. Always sacrifice quantity for quality when trying to make functional extracts. - [Read Cytostatic Factor (CSF) Extract Preparation for Spindle Assembly Protocol]
Protocol for cytostatic factor extract preparation for spindle assembly. The quality of the eggs is essential for good CSF extracts. Always sacrifice quantity for quality when trying to make functional extracts. Discard any batches of eggs that have "puff balls" or activated eggs that constitute more than 10% of the eggs. Use laid eggs and collect eggs at about 16 to 17 hours after priming with Progesterone (found in Pregnant Mare Serum Gonadotropin (PMSG)). - [Read Cytostatic Factor (CSF) Extract Preparation for Xenopus Spindle Assembly Protocol]
The simplest way to analyze proteins is in unfractionated extracts. However, it is often desirable to fractionate proteins, e.g, by size. This procedure extracts total protein from Arabidopsis samples. Typical yields are ~2-3 mg/ml (using rosette leaves) or 6-8 mg/ml (using young seedlings). - [Read Extraction of Total Protein from Arabidopsis Protocol]
This bioassay utilises cultured H-4-II-E rat hepatoma cells to assess the aryl hydrocarbon hydroxylase (AHH) inducing potencies of planar aromatic hydrocarbons and/or contaminated environmental samples. The response of the cells to pure test chemicals or extracts of mixtures is compared with their response to the standard 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). - [Read H-4-II-E Rat Hepatoma Cell Bioassay Protocol]
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]
In this protocol, extracts prepared from cells transfected with a chloramphenicol acetyltransferase (CAT) reporter plasmid are incubated with radiolabeled chloramphenicol. The acetylated products generated by the action of CAT are separated from the unmodified drug by thin-layer chromatography and quantitated by scraping the spots from the thin-layer plates and counting them by scintillation spectroscopy. - [Read Measurement of CAT in Extracts of Mammalian Cells Using Thin-layer Chromatography]
The protocol consists of a method for the generation of cytoplasmic extracts from mammalian cells (in this case, 293T cells) without the disruption of polyribosomes, the separation of ribosomal components and polyribosomes by sucrose gradient centrifugation, the isolation of mRNA from these fractions, and detection of mRNA by Northern blot analysis. - [Read Northern Blot Analysis of mRNA From Mammalian Polyribosomes Protocol]
This protocol provides a sufficient sample for several determinations of cAMP using the acetylation protocol. The method chosen for measuring the content of cyclic adenosine 3',5'-monophosphate (cyclic AMP or cAMP) in splenic B lymphocytes (B cells) is an enzyme linked immunoassay system. Protocol includes information on: Treatment of Cells and Preparation of Extracts; Reagents and Materials. - [Read Preparation of B-Lymphocyte Lysates for Cyclic AMP Determination]
Protocol provides a method for acheiving a sufficient sample for several determinations of cAMP. The protocol described for measuring the content of cyclic adenosine 3',5'-
monophosphate (cyclic AMP or cAMP) in cardiac myocytes is an enzyme-linked immunoassay system. Protocol includes information on: Treatment of Cells and Preparation of Extracts; Use of Environmental Chamber; Reagents and Materials. - [Read Preparation of Myocyte Lysates for Cyclic AMP Determination]
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.