Figure 8.

PIFs from P. patens Rescue the cop-Like Phenotype of Arabidopsis pifq Mutant Seedlings.

(A) The cop-like phenotype of dark-grown Arabidopsis pifq mutant seedlings is partially complemented by Pp-PIF overexpression. Col-0 and pifq mutant seedlings expressing Pro35S-YFP (pPPO30v1HA, empty vector control) as well as pifq mutant seedlings expressing Pro35S-driven Pp-PIF1:YFP, Pp-PIF2:YFP, or Pp-PIF2^ΔAPB:YFP were grown in darkness for 4 d. All transformed lines were analyzed in their segregating generation. Bar = 5 mm.

(B) Pp-PIF overexpression significantly complements the cop-like phenotype of Arabidopsis pifq mutant seedlings. Seedlings as described in (A) were used for quantification of hypocotyl length. Right panel shows comparison of empty vector control with pifq and Col-0 backgrounds. Data are shown as violin plots; white dots represent the median, and asterisks indicate P values (unpaired, two-tailed Student’s t test) of <0.05 (*), <0.01 (**), <0.001 (***), and >0.05 (n.s., not significant), respectively. The y axis scale was adjusted for maximal resolution in each plot.

(C) Pp-PIF overexpression restores the expression of PIF-dependent genes in Arabidopsis pifq mutants. The expression of the genes HB2, XTR7, PIL1, IAA19, and HFR1 was analyzed by quantitative PCR in 4 d dark-grown seedlings of Col-0, pifq, and pifq expressing Pro35S-YFP (pPPO30v1HA, empty vector control) or Pro35S-Pp-PIF1:YFP, Pro35S-Pp-PIF2:YFP, and Pro35S-Pp-PIF2^ΔAPB:YFP, respectively. Data were normalized to PP2AA3 mRNA. All transformed lines were analyzed in their nonsegregating generation. Technical replicates (repeats within an experiment) are shown as circles; bars represent the mean. The y axis scale was adjusted for maximal resolution in each plot. Gene accession numbers are listed in the Supplemental Methods. For biological replicates, refer to Supplemental Figure 16.