Figure 5.
Seedlings expressing NLS-ΔN SPA2 are insensitive to far-red light. A, Visual phenotype of the indicated genotypes grown in darkness or in 30 μmol m−2 s−1 continuous far-red light (FRc) for 4 d. B, Hypocotyl length of seedlings of the indicated genotypes grown under various fluence rates of FRc for 4 d. SPA2-HA and NLS ΔN SPA2-HA seedlings are in the spa1 spa2 spa3 mutant background. Error bars indicate the sem. n= 9–25 seedlings. C, Immunodetection of HY5 protein levels. Seedlings were grown in darkness for 4 d and then shifted to FRc (1 µmol m−2 s−1) for 6 h. HYS was detected using α-HY5 antibody. HSC70 levels, detected by α-HSC70, are shown as a loading control. All transgenes were expressed under the control of the constitutive SPA2 promoter. ΔN SPA2 carried an artificial NLS to replace the missing NLS located in the N-terminal domain of full-length SPA2.