Fig. 5
Evolutionarily conserved function of subclass III SnRK2 in ABA- and osmostress signaling. a SnRK2 genes from K. nitens, P. patens and Arabidopsis were fused to the PpSnRK2D gene promoter and introduced into QKO protonemata with PpLEA1-GUS by particle bombardment. After bombardment protonemata were treated with or without 10 µM ABA for 1d. b SnRK2 genes from Arabidopsis were fused to the PpSnRK2D gene promoter and introduced into QKO protonemata with Em-GUS and Ubi-LUC by particle bombardment. After bombardment protonemata were treated with or without 0.4 M mannitol for 1d. Levels of gene expression are represented by GUS per LUC ratio. Error bars indicate the SE (n = 4). *P < 0.05, **P < 0.01, ***P < 0.001 compared with the PpSnRK2D effector of QKO with ABA (a) or with mannitol (b). n.s., not significant. c, d Two independent transgenic P. patens plants that stably express Arabidopsis subclass I SnRK2.5, Subclass II SnRK2.8, or subclass III SnRK2.6 under PpSnRK2D gene promoter in QKO background were treated with 0.4 M mannitol for 30 min and subjected to the in-gel phosphorylation assay (c), or treated by 0.4 M mannitol solution for 15 min followed by Evans Blue staining to visualize the dead cells (d). Scale bars, 1 cm. WT, wild-type
