Figure 4.

Induction of ABA-Responsive Genes in Transgenic Plants Expressing the AtPLC1 Antisense and AtIP5PII Sense Transgenes.

Two independent lines for each construct were grown on plates for 2 weeks, and the seedlings were transferred to a hydroponic medium (Aoyama and Chua, 1997). After 2 days, the medium was replaced with fresh medium containing either Dex (30 μM) or ABA (50 μM) or both. Total RNA was isolated at various times (0, 4, and 24 hr), and RNA gel blots were hybridized with RD29a, KIN2, RD22, and COR47 probes and 18S rDNA. The vector control line contained the pTA211 plasmid alone. For details, see Methods. ABA-0, plants collected at 0 hr in the ABA medium; ABA-4, plants incubated with ABA (50 μM) for 4 hr; DEX-24, plants incubated with Dex (30 μM) for 24 hr; DEX-24/ABA-4, plants incubated with Dex (30 μM) for 24 hr followed by an additional 4 hr with ABA (50 μM).