pHIS2 is a reporter vector that can be used in yeast one-hybrid assays to identify and characterizeDNA-binding proteins. The vector was specifically designed for use with the BD Matchmaker™ One-Hybrid Library Construction & Screening Kit (#K1617-1). It contains a HIS3 nutritional reporter gene,located downstream of a multiple cloning site (MCS) and the minimal promoter of the HIS3 locus(PminHIS3). Cis-acting DNA sequences, or DNA target elements, can be inserted into the MCS andused as baits to screen GAL4 AD/cDNA fusion libraries for proteins that interact with the targetsequence. A protein-DNA (or one-hybrid) interaction can be detected by performing the assay in ayeast strain such as Y187 that is auxotrophic for histidine. Positive one-hybrid interactions driveexpression of the HIS3 reporter gene, which enables the host cell to grow on histidine-deficientmedia.