Phospholipase Dα6 and phosphatidic acid regulate gibberellin signaling in rice
Huasheng Cao, Rong Gong, Shu Yuan, Yuan Su, Weixin Lv, Yimeng Zhou, Qingqing Zhang, Xianjun Deng, Pan Tong, Shihu Liang*, Xuemin Wang,** & Yueyun Hong1,***
EMBO reports
Abstract
Phospholipase D (PLD) hydrolyzes membrane lipids to produce phosphatidic acid (PA), a lipid mediator involved in various cellular and physiological processes. Here, we show that PLDa6 and PA regulate the distribution of GIBBERELLIN (GA)-INSENSITIVEDWARF1 (GID1), a soluble gibberellin receptor in rice. PLDa6-knockout (KO) plants display less sensitivity to GA than WT, and PA restores the mutant to a normal GA response. PA binds to GID1, as documented by liposome binding, fat immunoblotting, and surface plasmon resonance. Arginines 79 and 82 of GID1 are two key amino acid residues required for PA binding and also for GID1’s nuclear localization. The loss of PLDa6 impedes GA-induced nuclear localization of GID1. In addition, PLDa6-KO plants attenuated GAinduced degradation of the DELLA protein SLENDER RICE1 (SLR1).These data suggest that PLDa6 and PA positively mediate GA signaling in rice via PA binding to GID1 and promotion of its nuclear translocation.
Keywords: gibberellin signaling; GID1 receptor; phosphatidic acid;Phospholipase; rice