Hypothetical light signaling cascades. (A) Light signaling transduction and transcriptional regulation network of light response in higher plants. (B) Hieratical Clustering Analysis (HCA) of gene expression profiling of light signaling related gene under UV-B irradiation. Abbreviations: AtCHS, naringenin-chalcone synthase, At5g13930; AtMYB12, At2g47460; AtC4H, cinnamate-4-hydroxylase, At2g30490; COP1, CONSTITUTIVE PHOTOMORPHOGENIC 1, At2g32950; CRY3, CRYPTOCHROME 3, At5g24850; ELIP1, EARLY LIGHT-INDUCABLE PROTEIN 1, At3g22840; FAR1, FAR-RED IMPAIRED RESPONSE 1, At4g15090; FHL, FAR-RED-ELONGATED HYPOCOTYL1-LIKE, At5g02200; FHY1, FRY1, PAT3, FAR-RED ELONGATED HYPOCOTYLS 1, At2g37678; FHY3, FAR-RED ELONGATED HYPOCOTYLS 3, At3g22170; GPX7, GLUTATHIONE PEROXIDASE 7, At4g31870; HY5, ELONGATED HYPOCOTYL 5, At5g11260; HYH, HY5-HOMOLOG, At3g17609; MKP1, MITOGEN-ACTIVATED PROTEIN KINASE PHOSPHATASE 1, At3g55270; MYB111, At5g49330; MYB4, At4g38620; PAP, MYB75, At1g56650; phyA, FHY2, hy8, PHYTOCHROME A, At1G09570; SIG5, SIGMA FACTOR 5, At5g24120; SWA3, WALK8, SLOW WALKER 3, At1g16280; UVR8, UV REPAIR DEFECTIVE 8, At5g63860.