Fig. 4. GA regulates miR159 levels via the DELLA-dependent GA signalling pathway. (A) RNA gel-blot analysis of miR159, MYB33 and SOC1 from wild-type (WT), gai, ga1-3 and ga1-3 gai-t6 rga-24 plants grown in long days (LD) in the presence (+GA) or absence (–GA) of gibberellin (100 µM GA₃ sprayed twice per week). The blots were stripped and re-analysed with miR167 and ELF4a probes (RNA controls). (B) RNA gel-blot analysis of miR159 levels in wild-type and sln1-dwarf mutant barley (Hordeum vulgare). 5S rRNA was used as RNA control.