PYL9 is involved in the regulation of ABA signaling during tomato fruit ripening. (31st August 2019)

• Record Type: Journal Article
• Authors: Kai, Wenbin; Wang, Juan; Liang, Bin; Fu, Ying; Zheng, Yu; Zhang, Wenbo; Li, Qian; Leng, Ping
• Editors: Costa, Fabrizio
• Is Part Of: Journal of experimental botany. Volume 70:Number 21(2019)
• Page Start: 6305
• Page End: 6319
• Publication Date: 2019-08-31
• Subjects: ABA receptor PYL -- ABA signaling -- flower abscission -- fruit ripening -- SlPYL9-OE/RNAi -- tomato; Botany -- Periodicals; Botany, Experimental -- Periodicals; Plant physiology -- Periodicals; 580
• DOI: 10.1093/jxb/erz396
• Languages: English
• ISSNs: 0022-0957

Abstract

Abstract: Abscisic acid (ABA) regulates fruit ripening, yet little is known about the exact roles of ABA receptors in fruit. In this study, we reveal the role of SlPYL9, a tomato pyrabactin resistance (PYR)/pyrobactin resistance-like (PYL)/regulatory component of ABA receptors (RCAR) protein, as a positive regulator of ABA signaling and fruit ripening. SlPYL9 inhibits protein phosphatase-type 2C (PP2C2/6) in an ABA dose-dependent way, and it interacts physically with SlPP2C2/3/4/5 in an ABA-dependent manner. Expression of SlPYL9 was observed in the seeds, flowers, and fruits. Overexpression and suppression of SlPYL9 induced a variety of phenotypes via altered expression of ABA signaling genes ( SlPP2C1/2/9, SlSnRK2.8, SlABF2 ), thereby affecting expression of ripening-related genes involved in ethylene release and cell wall modification. SlPYL9 -OE/RNAi plants showed a typical ABA hyper-/hypo-sensitive phenotype in terms of seed germination, primary root growth, and response to drought. Fruit ripening was significantly accelerated in SlPYL9 -OE by 5–7 d as a result of increased endogenous ABA accumulation and advanced release of ethylene compared with the wild-type. In the SlPYL9- RNAi lines, fruit ripening was delayed, mesocarp thickness was enhanced, and petal abscission was delayed compared with the wild-type, resulting in conical/oblong and gourd-shaped fruits. These results suggest that SlPYL9 is involved in ABA signaling, thereby playing a role in the regulation of flower abscission and fruit ripening in tomato. Abstract : ABA receptor PYL9 plays a role in the regulation of flower abscission and fruit ripening in tomato by modulating ABA signaling components, which regulates expression of related genes.