SPYing on GA signaling and plant development

It has been ten years since the SPINDLY (SPY) locus was first identified from a screen of mutagenized wild type Arabidopsis seeds by selecting for germination in the presence of a gibberellin (GA) biosynthesis inhibitor (Jacobsen and Olszewski 1993). Since then research into this novel protein, an O-GlcNAc transferase (OGT), has revealed some fascinating and surprising results. SPY was originally described as a negative regulator specific to the GA signal transduction pathway, but recent research suggests that SPY is involved in additional aspects of plant development. SPY is also being investigated in barley, petunia and rice, adding to the complex story that is SPY.