Suppliers of Reporter Assay Screening Systems Courtesy of Applied BiosystemsTarget practice: Researchers can employ reporter assays to study a variety of cellular processes. Rarely is the product of a gene readily distinguishable from the myriad mRNA and protein complements that exist in a cell at any point in time. But researchers can skirt this obstacle by placing a "reporter gene" under the same controls as the gene of interest. Reporter genes have easily measurable phenotypes that form th

The Scientist 15[15]:25, Jul. 23, 2001 PROFILE Suppliers of Reporter Assay Screening Systems  E-mailarticle Company Product Reporter Gene Reporter Chemistry No. Tests* Price Amersham Pharmacia Biotech (800) 526-3593 www.apbiotech.com Quan-T-CAT [3H] Assay System CAT [3H]-acetylated, biotinylated chloramphenicol 100 $450 Applied Biosystems (800) 345-5224 www.appliedbiosystems.com Gal-Screen Reporter Gene Assay for Mam

Microarrays, or "gene chips," have become valuable tools for studying changes in gene expression; detecting genetic mutations and polymorphisms; analyzing drug resistance and disease susceptibility; and sequencing unknown DNA. The microarray, which consists of cloned genes, PCR products, or synthetic oligonucleotides immobilized on a microscope slide, is analyzed by hybridization with target DNA or RNA that is labeled with radioisotopes or fluorescent dyes.1 For example, total mRNA isolated from

Suppliers of 2-D Electrophoresis Equipment Courtesy of Bio-RadBio-Rad's Mini-PROTEAN 3 system Graphic: Leza BerardoneThe inevitable inventory of genes that will be produced by the Human Genome Project heralds the start of a new era: the Age of Proteomics. Although DNA is the blueprint for life, it is the set of proteins that are actually transcribed and translated that determine the function of a particular cell. Proteomics is the study of the complete protein complement of the cell, tissue, o

The patterns of gene expression can help determine what makes a neuron different in form and function from a lymphocyte and how each responds to external stimuli. Ascertaining these patterns during development or in the course of disease is now more common and has a higher level of importance than ever before. Conventional techniques for determining changes in gene expression include Northern blots, serial analysis of gene expression (SAGE), and cDNA microarrays. RAGE, (rapid analysis of

Cytokines, unique growth factors that are secreted by various cells of the body, include interleukins (ILs), interferons (IFNs), and tumor necrosis factors (TNFs). These proteins bind to target cell surface receptors and activate cell proliferation and/or differentiation. Until recently, research that quantifies levels of cytokine-specific mRNA using traditional methods such as the northern blot, slot blot, quantitative RT-PCR, and ribonuclease protection assay (RPA) has been labor-intensive and