Multiple Self-Splicing Introns in Bacteriophage T4: Evidence from Autocatalytic GTP Labeling of RNA in vitro

摘要

RNA from T4-infected cells yielded multiple end-labeled species when incubated with alpha-phosphorus 32-GTP under self-splicing conditions. One of these corresponds to the previously identified intron from the td gene of T4, while others appear to represent additional group 1 introns in T4. Two loci distinct from the td gene were found to hybridize to a mixed alpha-phosphorus 32-GTP-labeled T4 RNA probe. These mapped in or near the unlinked genes nrdB and nrdC. A fragment from the nrdB region that contains the intron has been cloned and shwon to generate characteristic group 1 splice products with RNA synthesized in vivo and in vitro. Multiple introns, and the prospect that these occur within several genes in the same metabolic pathway, suggest a possible regulatory role for splicing in T4.