Summary

to be induced by ABA in Arabidopsis seedlings ([11] andbotanik.uni-wuerzburg.de (R.H.)by closure (Figure 1A). EDXA analysis showed that exposureThe response of stomata to a reduction in atmospheric relative humidity (rh) is made up of rapid, transitory opening followed this cluster, 131 genes belong to the class of guard cell-enriched genes (Table S1F). ABA-Regulated GC Genes To identify guard cell genes sensitive to ABA, we sprayed plants with the drought hormone. Within the pool of guard cell-expressed genes, 1,550 appeared sensitive to ABA, with 1,080 being upregulated and 470 being downregulated8These authors contributed equally to this workJoerg Fromm,2 Wolfram Hartung,1 Khaled A.S. Al-Rasheid,