Physical evidence for the temporal transition of transcription in bacteriophage λ

Autor: Erdile, Lorne F., Schnös, Maria, Inman, Ross B.
Zdroj: Molecular and General Genetics MGG; August 1982, Vol. 186 Issue: 4 p558-565, 8p
Abstrakt: A high proportion of intracellular ? DNA molecules are found to have D-loops, when isolated under four different conditions: (1) ?Ots after 7 min at 31°C in the presence of chloramphenicol; (2) ?Ots after 7 min at 31° C without chlormaphenicol; (3) ?Ost after 30 min at 42° C; and (4) ?cIIcIII after 50 min at 37° C. The great majority of these D-loops contain RNA and are produced by E. coli RNA polymerase. In the presence of chloramphenicol, D-loops are mostly limited to the immediate early regions of the major leftward and rightward operons. At early times, with no chloramphenicol present, D-loops map primarily within the delayed early regions of the two major operons. At late times, D-loops are found mostly within the major late operon of the bacteriophage DNA. This physical evidence corroborates evidence of the temporal transition in ? transcription obtained by other means. Chloramphenicol is shown to block the transition from immediate early to delayed early transcription.
Databáze: Supplemental Index