The NF YC RGL2 module integrates GA and ABA signalling to regulate seed germination in Arabidopsis
The antagonistic crosstalk between gibberellic acid (GA) and abscisic acid (ABA) plays a pivotal role in the modulation of seed germination. However, the molecular mechanism of such phytohormone interaction remains largely elusive. Here we show that three Arabidopsis NUCLEAR FACTOR Y C (NF YC) homologues NF YC3, NF YC4 and NF YC9 redundantly modulate GA and ABA mediated seed germination. These NF YCs interact with the DELLA protein RGL2, a key repressor of GA signalling. The NF YC RGL2 module targets ABI5, a gene encoding a core component of ABA signalling, via specific CCAAT elements and collectively regulates a set of GA and ABA responsive genes, thus controlling germination. These results suggest that the NF YC RGL2 ABI5 module integrates GA and ABA signalling pathways during seed germination.
Nature communications