Graduate School of Life Sciences, Tohoku University, Miyagi 890-8577, Japan.
Bioscience and Biotechnology Center, Nagoya University, Aichi 464-8601, Japan.
Science. 2018 Jul 13;361(6398):181-186. doi: 10.1126/science.aat1577.
Most plants do poorly when flooded. Certain rice varieties, known as deepwater rice, survive periodic flooding and consequent oxygen deficiency by activating internode growth of stems to keep above the water. Here, we identify the gibberellin biosynthesis gene, (), whose loss-of-function allele catapulted the rice Green Revolution, as being responsible for submergence-induced internode elongation. When submerged, plants carrying the deepwater rice-specific haplotype amplify a signaling relay in which the gene is transcriptionally activated by an ethylene-responsive transcription factor, OsEIL1a. The SD1 protein directs increased synthesis of gibberellins, largely GA, which promote internode elongation. Evolutionary analysis shows that the deepwater rice-specific haplotype was derived from standing variation in wild rice and selected for deepwater rice cultivation in Bangladesh.
大多数植物在水淹时生长不良。某些被称为深水稻的水稻品种通过激活茎节间的生长，使其保持在水面以上，从而在周期性水淹和随之而来的缺氧条件下存活。在这里，我们鉴定出赤霉素生物合成基因 (), 其功能丧失等位基因导致了水稻绿色革命的爆发，该基因负责淹水诱导的节间伸长。在被淹没时，携带深水稻特有单倍型的植物会放大信号转导，其中基因被乙烯响应转录因子 OsEIL1a 转录激活。SD1 蛋白指导赤霉素（主要是 GA）的合成增加，从而促进节间伸长。进化分析表明，深水稻特有的单倍型是从野生稻的固定变异中衍生而来的，并在孟加拉国的深水稻种植中被选择。
