FIG. 1.

Heat shock induction of groES and groEL genes. (A) Pattern of heat shock induction. Heat shocks were initiated at 0 and 150 min (vertical arrows). The culture was returned to normal temperature at 120 min and kept at 30°C for 30 min. (B) Transcriptional maps and Northern hybridizations of samples taken at the indicated times. The heat shock pattern was as indicated for panel A. The probes are shown by solid lines. The sizes of the hybridizing bands (in kilobases) are indicated by arrowheads on the left and right of the panels. Note that there is a reinduction of expression after the second heat shock. 16S rRNA was hybridized as a control.