DESCRIPTION (Abstract of the Core) This core was organized to provide the following expertise, services and reagents to members of the Program Project: plasmid preparation and cDNA/cRNA probe labeling; RNA extraction and Northern/RNase protection analysis; isolation of nuclei and nuclear run-on analysis; extraction and analysis of genomic DNA; Western blotting and immunoprecipitation; transient and stable transfection, CAT and luciferase assays; analysis of trans-acting factors with DNase I footprinting, EMSA and methylation interference; PCR cloning, mutagenesis and RT-PCR; and cDNA array and Affymetrix chip analysis and probe preparation. Since the last competing renewal in 1995, 49% of the 186 publications produced by the group have utilized the facilities and expertise provided by this core.