radiolabeled Protocols

Category: Molecular Biology Protocols: Carbohydrate Protocols

The method allows the detection and quantification of glycosyltransferase activity using an ELISA-based procedure and carbohydrate-specific monoclonal antibodies. Avoids the use of radiolabeled substrates. Bruce A. Macher~Professor of Chemistry and Biochemistry, San Francisco State University, San Francisco, CA - [Read A Sensitive ELISA-Based Assay for Glycosyltransferases]

Category: Cell Biology and Cell Culture: In Vitro Reconstitution Protocols

The ability to synthesize RNA in the lab is critical to many techniques.Radiolabeled and nonisotopically labeled RNA probes, generated in small scale transcription reactions can be used in blot hybridizations and nuclease protection assays. This article includes information on: Requirements For Transcription, RNA Phage Polymerases, Template Options: Plasmids, PCR Products, Oligonuclotides and cDNA, Sense or Antisense, Conventional Or Large Scale Synthesis, Products for In Vitro Transcription. - [Read Basic Information on In Vitro Transcription]

Category: Antibody Protocols: Antibody Labeling Protocols

Protocol for the detection of autoantibodies with self-assembling radiolabeled antigen tetramers. - [Read Detection of Autoantibodies with Self-Assembling Radiolabeled Antigen Tetramers Protocol]

Category: Immunology

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]

Category: DNA Protocols: DNA Sequencing Protocols

Methods for DNA sequencing.  Includes: Bst-catalyzed radiolabeled DNA sequencing; Radiolabeled sequencing gel preparation, loading, and electrophoresis; Taq-polymerase catalyzed cycle sequencing using fluorescent-labeled dye primers; Taq-polymerase catalyzed cycle sequencing using fluorescent-labeled dye terminator reactions; Sequenase[TM] catalyzed sequencing with dye-labeled terminators; etc. - [Read DNA Sequencing Methods]

Category: Viral Manipulation Protocols: M13 Phage Manipulation Protocols

Protocol used chiefly to generate large stocks of double-stranded DNA of strains of M13 that are routinely used as cloning vectors. Large amounts of single-stranded DNA of an individual recombinant may occasionally be needed for specific purposes, e.g., to generate many preparations of a particular radiolabeled probe or to construct large numbers of site-directed mutants. - [Read Large-scale Preparation of Single-stranded and Double-stranded Bacteriophage M13 DNA Protocol]

Category: DNA Protein Interactions Protocols: Dnase Footprinting Assay Protocols

Dnase I is used to fragment a radiolabeled target DNA in the presence and absence of a nuclear extract.  A "footprint" is generated when a protein binds to the target and protects a specific segment of DNA from the nucleolytic activity of Dnase I. By comparing the electrophoretic mobility of the Dnase I cleavage products to those of a sequence ladder derived from the same DNA fragment, the position(s) of the DNA sequences recognized by DNA-binding proteins can be determined. - [Read Mapping Protein-binding Sites on DNA by Dnase I Footprinting Protocol]

Category: Nucleic Acid Modification Protocols: Nucleic Acid Radiolabeling Protocols

Preparations of RNA containing an mRNA of interest are hybridized to a radiolabeled single-stranded RNA probe. The method can be used to quantitate RNAs, to map the positions of introns, and to identify the locations of 5' and 3' ends of mRNAs on cloned DNA templates. - [Read Mapping RNA with Ribonuclease and Radiolabeled RNA Probes Protocol]

Category: Reporter Gene Assays: Cat Assays Protocols

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]

Category: Signalling Signal Transduction Protocols

Protocol describes a competitive ligand binding assay for cortical neurotrophin receptors. Following binding in the presence of competitor, the bound radiolabeled ligand is cross-linked to the receptor. The cells are lysed and the ligand-receptor complexes are immunoprecipitated using a pan-trk (tyrosine kinase receptor) antibody. Protocol includes:Preparation of Cortical Tissue for Competitive Crosslinking, Competitive Binding, Crosslinking Ligand to Receptor, Lysis and Immunoprecipitation etc - [Read Protocol for Competitive Ligand Binding to Cortical Receptor using Crosslinking]

Category: Cell Biology and Cell Culture: In Vitro Reconstitution Protocols

Protocol describes an RNA Polymerase III (Pol III) transcription assay using an extract or proteins of choice. Pol III is the polymerase responsible for transcribing 5S RNA, tRNAs, and other small RNAs. α-Amanitin inhibits Pol II transcription in the assay. The newly-transcribed, radiolabeled RNA is visualized by autoradiography following Urea Polyacrylamide gel electrophoresis. - [Read Protocol for Polymerase III In Vitro Transcription]

Category: Cell Biology and Cell Culture: In Vitro Reconstitution Protocols

In this protocol nuclei isolated from cells expressing the gene of interest are incubated with radiolabeled UTP which is incorporated into nascent RNA transcripts by RNA polymerase molecules that were actively transcribing at the time the cells were harvested. Because very little denovo initiation of RNA synthesis occurs in isolated nuclei, transcription of the target gene can be measured by hybridizing the radiolabeled RNA to an excess of the target gene immobilized on a nitrocellulose or nylon - [Read Protocol for Transcriptional Run- On Assays]

Category: Nucleic Acid Purification Protocols

Radiolabeled nucleic acids, including oligonucleotides, can be separated from unincorporated radiolabel by quantitative, differential precipitation with the cationic detergent cetylpyridinium bromide (CPB).  The nucleic acids are first precipitated from aqueous solution with CPB. - [Read Purification of Radiolabeled Oligonucleotides by Precipitation with Cetylpyridinium Bromide Protocol]

Category: Nucleic Acid Modification Protocols: Nucleic Acid Radiolabeling Protocols

In this procedure, synthesis of cDNA is carried out in the presence of saturating concentrations of all four dNTPs and trace amounts of a single radiolabeled dNTP.  After subtraction hybridization, the enriched single-stranded cDNA is radiolabeled to high specific activity in a second synthetic reaction by extension of random oligonucleotide primers using the Klenow fragment of E. coli DNA polymerase. - [Read Radiolabeling of Subtracted cDNA Probes by Random Oligonucleotide Extension Protocol]

Category: Bacterial Protocols

Bacterial colonies growing on agar plates are transferred en masse to nitrocellulose filters. The spatial arrangement of colonies on the plates is preserved on the filters. After transfer, the filters are processed for hybridization to an appropriate radiolabeled probe while the original (master) plate is incubated for a few hours to allow the bacterial colonies to regrow in their original positions. - [Read Screening Bacterial Colonies by Hybridization: Intermediate Numbers Protocol]

Category: Bacterial Protocols

Protocol used to screen a small number of bacterial colonies (<200) that are dispersed over several agar plates and are to be screened by hybridization to the same radiolabeled probe. The colonies are gridded onto a master plate and onto a nitrocellulose or nylon filter laid on the surface of a second agar plate. - [Read Screening Bacterial Colonies by Hybridization: Small Numbers 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: 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: Nucleic Acid Detection Protocols: Nucleic Acid Blotting Protocols

Protocol for southern hybridization of radiolabeled probes to nucleic acids immobilized on membranes. Protocol describes how to carry out Southern hybridizations at high stringency in phosphate-SDS buffers.  Although a wide variety of formats are available, most Southern hybridizations are carried out in heat-sealable bags, roller bottles, or plastic boxes. - [Read Southern Hybridization of Radiolabeled Probes to Nucleic Acids Immobilized on Membranes Protocol]

Category: PCR Protocols: cDNA Synthesis Protocols

Protocol describes the preparation of subtracted cDNA probes by hybridization to an mRNA driver, followed by purification of the single-stranded radiolabeled cDNA by hydroxyapatite chromatography.  Before preparing the probe, it is a good idea to have filters (which contain the cDNA library to be screened) ready to hybridize. - [Read Synthesis of Radiolabeled, Subtracted cDNA Probes Using Oligo(dT) as a Primer Protocol]

Category: Viral Manipulation Protocols: M13 Phage Manipulation Protocols

A synthetic oligonucleotide annealed to single-stranded DNA derived from a recombinant bacteriophage M13 or phagemid template is used to prime the synthesis of complementary radiolabeled DNA. Synthesis is catalyzed by the Klenow fragment of E. coli DNA polymerase I, which extends the annealed primer for various distances along the single-stranded template DNA. - [Read Synthesis of Single-stranded DNA Probes of Defined Length from Bacteriophage M13 Templates Protocol]

Category: Viral Manipulation Protocols: M13 Phage Manipulation Protocols

Technique yields a heterogeneous population of short radiolabeled molecules 200-300 nucleotides in length. These probes are synthesized, as in Synthesis of Single-stranded DNA Probes of Defined Length from Bacteriophage M13 Templates, by extension of an oligonucleotide primer on a single-stranded DNA template. The radiolabeled products of the reaction are then separated from the template by electrophoresis through a denaturing gel from which they are eluted directly into hybridization buffer. - [Read Synthesis of Single-stranded DNA Probes of Heterogeneous Length from Bacteriophage M13 Templates]