Revisiting the role of delta-1-pyrroline-5-carboxylate synthetase in drought-tolerant crop breeding
Xuanjun Feng,
Yue Hu,
Weixiao Zhang,
Rongqian Xie,
Huarui Guan,
Hao Xiong,
Li Jia,
Xuemei Zhang,
Hanmei Zhou,
Dan Zheng,
Ying Wen,
Qingjun Wang,
Fengkai Wu,
Jie Xu,
Yanli Lu
Affiliations
Xuanjun Feng
State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Wenjiang 611130, Sichuan, China; Maize Research Institute of Sichuan Agricultural University, Wenjiang 611130, Sichuan, China
Yue Hu
Maize Research Institute of Sichuan Agricultural University, Wenjiang 611130, Sichuan, China
Weixiao Zhang
Maize Research Institute of Sichuan Agricultural University, Wenjiang 611130, Sichuan, China
Rongqian Xie
Maize Research Institute of Sichuan Agricultural University, Wenjiang 611130, Sichuan, China
Huarui Guan
Maize Research Institute of Sichuan Agricultural University, Wenjiang 611130, Sichuan, China
Hao Xiong
Maize Research Institute of Sichuan Agricultural University, Wenjiang 611130, Sichuan, China
Li Jia
Maize Research Institute of Sichuan Agricultural University, Wenjiang 611130, Sichuan, China
Xuemei Zhang
Maize Research Institute of Sichuan Agricultural University, Wenjiang 611130, Sichuan, China
Hanmei Zhou
Maize Research Institute of Sichuan Agricultural University, Wenjiang 611130, Sichuan, China
Dan Zheng
Maize Research Institute of Sichuan Agricultural University, Wenjiang 611130, Sichuan, China
Ying Wen
Maize Research Institute of Sichuan Agricultural University, Wenjiang 611130, Sichuan, China
Qingjun Wang
Maize Research Institute of Sichuan Agricultural University, Wenjiang 611130, Sichuan, China
Fengkai Wu
Maize Research Institute of Sichuan Agricultural University, Wenjiang 611130, Sichuan, China
Jie Xu
Maize Research Institute of Sichuan Agricultural University, Wenjiang 611130, Sichuan, China
Yanli Lu
State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Wenjiang 611130, Sichuan, China; Maize Research Institute of Sichuan Agricultural University, Wenjiang 611130, Sichuan, China; Corresponding author.
The delta-1-pyrroline-5-carboxylate synthetase (P5CS) gene exercises a protective function in stressed plants. However, the relationship between proline accumulation caused by P5CS and abiotic stress tolerance in plants is not always clear, as P5CS overexpression has been reported to repress plant growth under normal conditions in several reports. We re-evaluated the role of P5CS in drought-tolerant rice breeding by expressing the AtP5CS1 and feedback-inhibition-removed AtP5CS1 (AtP5CS1F128A) genes under the regulation of an ABA-inducible promoter to avoid the potential side effects of P5CS overexpression under normal conditions. ABA-inducible AtP5CS1 and AtP5CS1F128A increased seedling growth in a nutrient solution (under osmotic stress) and grain yield in pot plants. However, the evidently deleterious effects of AtP5CS1 on grain quality, tiller number, and grain yield in the field indicated the unsuitability of P5CS for drought-tolerance breeding.
