Gene-Specific Messenger RNA: Isolation by the Deletion Method

Messenger RNA molecules, homologous to a small portion of the genome of bacteriophage T4, have been isolated. RNA fragments specific to the rII A and the rII B cistrons have been separated by hybridization with DNA isolated from appropriate deletion mutants. An RNA species homologous in nucleotide sequence to a defined part of the rII A cistron has been identified.