Figure 3.

AtPirin1 Transcript Levels Are Regulated by ABA and Low-Fluence Red Light.

(A) Transcript levels of the AtPirin1 gene are induced by ABA. AtPirin1 transcript levels were examined by relative quantitative RT-PCR in 9-day-old light-grown Arabidopsis plants sprayed with 100 μM ABA (+) or distilled water (−). The ABA-responsive Rab18 transcript (Lang and Palva, 1992) served as a positive control for the assay.

(B) Transcript levels of the AtPirin1 gene are induced by red light. AtPirin1 transcript levels were examined by relative quantitative RT-PCR in seedlings grown for 6 days in the dark and treated with a mock pulsed light (d) or irradiated with a single pulse of low-fluence blue light (b) or low-fluence red light (r).

18S rRNA was used as an endogenous RT-PCR standard. Representative experimental replicates are shown.