AtWSCP gene expression in dark- and light-grown seedlings. (A) Promoter–β-glucuronidase (GUS) analysis in 3-d-old etiolated and light-grown seedlings of a transgenic line expressing GUS under the control of the AtWSCP promoter (AtWSCP promoter::GUS). (B) AtWSCP transcript levels analyzed by semiquantitative RT-PCR in 3-d-old etiolated seedlings before (0 h) and after 3, 6, 9, and 24 h of white light exposure. Controls show data for Actin as constitutively expressed gene and LHCBII as light-induced gene. (C) AtWSCP protein contents in etiolated and light-grown seedlings, respectively. For comparison, Ponceau-stained blots are shown each containing 50 µg of loaded protein.