A RAPID PROCEDURE FOR THE ISOLATION OF C(0)T-1 DNA FROM PLANTS

In situ hybridization (ISH) for the detection of single- or low-copy s equences, particularly large DNA fragments cloned into YAC or BAC vect ors, generally requires the suppression or ''blocking'' of highly-repe titive DNAs. C(0)t-1 DNA is enriched for repetitive DNA elements, high or moderate in copy number, and can therefore be used more effectivel y than total genomic DNA to prehybridize and competitively hybridize r epetitive elements that would otherwise cause nonspecific hybridizatio n. C(0)t-1 DNAs from several mammalian species are commercially availa ble, however, none is currently available for plants to the best of ou r knowledge. We have developed a simple 1-day procedure to generate C( 0)t-1 DNA without the use of specialized equipment.