Fig. 7.

Direct interaction between phyB and SPA1 is necessary for phyB-mediated seed germination. a Schematic diagram of phyB-28, phyB-GFP ΔC and phyB-GFP FL proteins. b, c The C-terminal SPA1-interaction domain of phyB is necessary for phyB-mediated seed germination. phyB-GFP ΔC displays reduced germination compared to phyB-GFP FL lines, while phyB-28 displays slower germination compared to wild type (phyA-211 that contains wild type PHYB). The error bars indicate s.e.m. (n = 3). d The light-induced phosphorylation and degradation of TAP-PIF1 is defective in phyB-28 compared to wild type (phyA-211 that contains wild type PHYB). Total protein was extracted from four-day-old dark-grown seedlings either kept in darkness or exposed to continuous red light (3.5 μmolm⁻² s⁻¹) over time