Analysis of DNA Fragmentation Using the JAM Assay. By Shailaja Kasibhatla et al., The JAM assay is based on labeling nuclear DNA of cycling cells with [3H]thymidine and harvesting samples on glass fiber filters. Apoptosis will generate DNA fragments small enough to pass through the glass fiber filter, resulting in decreased radioactivity of the particular sample. Cell-mediated cytotoxicity or cell killing mediated by cytotoxic T lymphocytes (CTL) can also be measured by this technique. - [Read Analysis Of DNA Fragmentation Using The JAM Assay (Subscription Required)]
Includes Abbreviations, Background, and Procedure steps using BSA. The Bradford protein assay (1) is one of several simple methods commonly used to determine the total protein concentration of a sample. The method is based on the proportional binding of the dye Coomassie to proteins. The assay is colorimetric; as the protein concentration increases, the color of the test sample becomes darker. Coomassie absorbs at 595 nm. - [Read Bradford Protein Concentration Assay]
Protocol uses specific antibodies coupled to one of four fluorochromes: fluorescein isothiocyanate (FITC), R-phycoerythrin (PE), peridinin chlorophyll-a (PcP),
and allophycocyanin (APC). These fluorochromes can be used simultaneously to stain and analyze the expression patterns of four different proteins in the same sample. The
fluorochrome stained cell populations are analyzed using a FACSCalibur dual-laser flow cytometer. - [Read Characterization of Cells by Flow Cytometry Protocol]
Fluorochromes can be used simultaneously to stain and analyze the expression patterns of four different proteins in the same sample. The fluorochrome stained cell populations are analyzed using a FACSCalibur dual-laser flow cytometer. - [Read Characterization of Cells by Flow Cytometry Protocol]
Protocol for Competitive RT-PCR.For quantifying mRNA, we use a competitive RT-PCR protocol with internal standard RNAs. These are added in a defined quantity to the RNA sample prior to the RT reaction. The resulting standard cDNA is coamplified with the s - [Read Competitive RT-PCR Protocol]
In this protocol, sample and competitor RNAs are reverse transcribed (separately) in a pilot experiment. A constant amount of sample RT product is then combined with a 2-logserial dilution of competitor RT product for PCR. Procedure provides an approximate copy number for the sample, which is then fine-tuned by repeating the experiment with a series of twofold dilutions of competitor. The experiment includes controls for sample-to-sample variations in RT efficiency. - [Read Competitive RT-PCR: Estimation of Copy Number Protocol]
Confocal Microscopy and Protocols. Why use a confocal microscope? Fluorescence, Reflectance or Transmission? Which confocal microscope should you use? Confocal or 2-photon microscopy? Sample Preparation for confocal microscopy, Fixation, Immunolabeling, - [Read Confocal Microscopy and Protocols]
This bioassay utilizes cultured Hepa-lclc7 (Hepa-1) mouse hepatoma cells to assess the CYPlA1-inducing potency or cytotoxicity of pure test chemicals or environmental samples. In the Hepa-l induction test , the CYPlA1-inducing potency of the test sample is detected as increased aryl hydrocarbon hydroxylase (AHH) and 7-ethoxyresorufin O-deethylase (EROD) activities. - [Read CYP1A1-Inducing Potency and Cytotoxicity Test in the HEPA-1 Mouse Hepatoma Cell Line]
Protocol for detection of autoantibodies with self-assembling radiolabeled antigen tetramers. Details how to produce radiolabeled antigen-streptavidin tetramers for detection of antibodies by immunoprecipitation. Optionally, the antigen tetramers can be denatured to compare responses to folded and unfolded antigen in the same system. This technique can be applied to a large or small number of samples, and a given sample can be simultaneously assayed with multiple antigens. - [Read Detection of Autoantibodies with Self-Assembling Radiolabeled Antigen Tetramers Protocol]
Dried droplet Sample Preparation for MALDI.The discovery of this method allowed the application of laser desorption to proteins [2]. Drying a droplet of a protein/matrix solution remains the favorite method of most MALDI practitioners. Protocol for dried - [Read Dried droplet Sample Preparation for MALDI]
Protocol for ELISA assay for NGF. Includes: ABSORPTION OF THE POLYCLONAL AND PREIMMUNE SERUM; BLOCKING; SAMPLE PREPARATION; PREPARATION OF NGF STANDARDS; PROTEIN RECOVERY; DESIGNING THE PLATE; APPLYING THE STANDARDS AND SAMPLES; APPLYING THE MONOCLONAL; APPLYING SECONDARY ANTIBODY; APPLYING STREPTAVIDIN; CHROMAGEN DEVELOPMENT; READING THE PLATE. - [Read Enzyme-Linked ImmunoSorbent Assay (ELISA) for NGF Protocol]
The growth conditions of microbial cell cultures and the time of sample collection should be optimized and standardized when growing cells for protein extraction. Because cells may excrete proteases and other extracellular enzymes, and compounds in the medium may interfere with extraction, wash cultures with an isotonic buffer, such as PBS or sucrose before solubilization. - [Read Extraction and Solubilization of Total Protein from Microorganisms Protocol]
Protocol describes a method for performing isoelectric fractionation of a maize embryo sample using a multicompartment electrolyzer(MCE). This prefractionation of proteins having pIs within a certain pH interval is essential for allowing high loads of protein to be resolved on narrow and ultra-narrow immobilized pH gradients used in 2D electrophoresis. The isoelectric membranes in the MCE act like isoelectric traps capturing all the protein species having pIs encompassing the pI value of each... - [Read Fractionation of Maize Embryo Proteins for 2-D Gel Electrophoresis Using Multicompartment Electrolyz]
This protocol describes a method for constant-flow microinjection using the Pneumatic PicoPump (World Precision Instruments). This type of system is very simple and can be assembled on a relatively low budget. In this method, a constant flow of sample is delivered from the tip of the pipette, and the amount of sample injected into the cell is determined by how long the pipette remains in the cell. - [Read Gene Delivery by Direct Injection (Microinjection) Using a Controlled-Flow System Protocol]
DNA Isolation from museum specimens: 1) what's the best tissue to sample; 2) what's the best way to get DNA out of that tissue? 1) the easiest well-dried tissue to get, and 2) the easiest extraction methods you are comfortable doing. Travis Glenn. - [Read Getting DNA from Old Dead Stuff]
In brief, the reaction mixture, is prepared in exactly the same way as if the sample is to be stained or shadowed for electron microscopy, but once the... Gold labeling technique for electron microscopic identification and location of proteins. - [Read Gold labeling of proteins for electron microscopy]
DNA microarrays are an ordered arrangement of DNA molecules complementary to genes of interest that are "spotted" by robotic equipment onto a glass slide substrate. The expression of genes in cells can be monitored with microarrays by preparing cDNA from the mRNA of cells of interest and measuring the hybridization to the microarray. This protocol describes the labeling of genomic DNA for use as a probe for hybridization to the cDNA spotted on the array.
This Microarray Protocol Preparation of Fluorescent DNA Probes from Human mRNA protocol describes the production of probes labeled with the fluorescent dyes, Cy3 and Cy5, following the synthesis of cDNA from human mRNA and the hybridization of the probes to DNA microarrays.
A single step RNA isolation protocol using Phenol Chloroform Extraction and Acid Guanidinium Thiocyanate. This RNA isolation method uses the fact that guanidinium thiocyanate can simultaneously lyse the cells and inactive cellular RNAses during the initial RNA isolation step allow a single step in the method.
In Vitro Translated Xenopus Mos Kinase Assay Protocol. In response to progesterone, immature Xenopus oocytes mature to eggs that can be fertilized. The Mos protein kinase is essential for oocyte maturation, most likely due to its ability to activate the MAP kinase cascade. This MAP kinase cascade eventually leads to the activation of Cdc2/cyclin B and entry into M phase. In this protocol, tagged Mos kinase is translated in vitro, immunopurified, and used in a kinase assay.
Unlike spherical phage, such as T4 and λ, which have roughly equal weight ratios of protein to DNA, filamentous phage have about six times more protein than DNA; the protein therefore contributes substantially to the absorption spectrum.
3' Rapid Amplification of cDNA Ends RACE Using PCR Protocol. This protocol contains the steps for 3' end rapid amplification of mRNA by PCR. The first-strand cDNA is synthesized from total or poly(A+) RNA by priming from the poly-A tail of the mRNA using a oligo (dT) adaptor primer. The cDNA is then amplified via PCR using a gene-specific primer and an adaptor primer.
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 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.