Figure 8.

The Increase of SIPK Activity Induces the Expression of the HMGR Gene.

Tobacco leaves were transformed transiently with SIPK. SIPK^R, an inactive mutant of SIPK, was used as a control. Total RNA was isolated from samples collected at the times indicated after the application of DEX. Equal amounts of RNA (10 μg) were electrophoresed on a 1.2% formaldehyde-agarose gel and transferred to a Zeta-Probe membrane (Bio-Rad). The transcript levels of HMGR were determined by probing with an α-³²P-CTP random primer–labeled cDNA insert, as described in Methods. An ethidium bromide (EtBr)-stained gel was used to show equal loading of samples.