Ethylene-gibberellin signaling underlies adaptation of rice to periodic flooding ($) (Science)

The diverse responses of rice to flooding are really interesting. Many varieties die, some survive by essentially becoming metabolically quiescent to conserve their energy (which involves the Sub1 pathway), and some, called deepwater rice, respond through rapid elongation that elevates their leaves above the floodwaters. Kuroha et al. further characterize the molecular basis for the deepwater rice adaptation. They show that deepwater alleles (DWH) of the SEMIDWARF1 (SD1) gene (encoding a gibberellin biosynthetic gene, widely known through its role as “green-revolution” dwarfing gene) contribute to the flooding elongation response.  The SD1 gene in deepwater haplotypes is expressed at elevated levels in response to flooding-induced ethylene accumulation, leading to elevated gibberellin accumulation and internode elongation.  (Summary by Mary Williams) Science 10.1126/science.aat1577