title: The mechanism by which NaCl treatment alleviates PSI photoinhibition under chilling-light treatment.
abstract: The effects of chilling-light stress combined with additional stress on PSI and PSII photoinhibition and their interrelationship have not been known. To explore whether NaCl affects the PSI and PSII photoinhibition and their interrelationship under chilling-light treatment, the PSI and PSII activities were studied under chilling-light with or without NaCl treatment. The results showed that the extent of PSI and PSII photoinhibition both increased under chilling-light, while NaCl aggravated PSII photoinhibition and severely damaged cytochrome b₆/f complex but alleviated PSI photoinhibition. Moreover, DCMU had a similar effect as NaCl in this study, which indicates that NaCl alleviated PSI photoinhibition through reducing electrons transported to PSI. It was also showed that the increased damage to PSII by NaCl did not depend on the inhibition of PSII repair and PSI electron transportation. In conclusion, NaCl alleviated PSI photoinhibition by inhibiting electron transport from PSII under chilling-light conditions. In addition, PSII photoinhibition was not affected by PSI photoinhibition because of a full inhibition of PSII repair by chilling-light treatment. We also speculate that NaCl aggravates PSII photoinhibition by enhancing the damage instead of inhibiting the repair of it under chilling-light conditions.
authors.affiliation: State Key Laboratory of Crop Biology, Shandong Key Laboratary of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, China; Wheat Research Institute, Henan Academy of Agricultural Sciences, Zhengzhou, Henan 450002, China. Electronic address: luckytiger.com@163.com.
authors.forename: Cheng
authors.initials: C
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Crop Biology, Shandong Key Laboratary of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, China. Electronic address: Zhangzishantaian@163.com.
authors.forename: Zi-shan
authors.initials: ZS
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Crop Biology, Shandong Key Laboratary of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, China. Electronic address: gaohy@sdau.edu.cn.
authors.forename: Hui-yuan
authors.initials: HY
authors.lastname: Gao
authors.affiliation: State Key Laboratory of Crop Biology, Shandong Key Laboratary of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, China. Electronic address: fanxingli2008@163.com.
authors.forename: Xing-li
authors.initials: XL
authors.lastname: Fan
authors.affiliation: State Key Laboratory of Crop Biology, Shandong Key Laboratary of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, China. Electronic address: lebaby7@163.com.
authors.forename: Mei-jun
authors.initials: MJ
authors.lastname: Liu
authors.affiliation: Wheat Research Institute, Henan Academy of Agricultural Sciences, Zhengzhou, Henan 450002, China. Electronic address: hnlxd@126.com.
authors.forename: Xiang-dong
authors.initials: XD
authors.lastname: Li
mesh_terms: D002701:Chloramphenicol / Q000494:pharmacology; D018553:Cucumis sativus / Q000201:enzymology; D004237:Diuron / Q000494:pharmacology; D008027:Light; D045331:Photosystem I Protein Complex / Q000037:antagonists & inhibitors* / Q000378:metabolism; D045332:Photosystem II Protein Complex / Q000037:antagonists & inhibitors / Q000378:metabolism; D012965:Sodium Chloride / Q000494:pharmacology*; D013312:Stress, Physiological / Q000187:drug effects
chemical_list: D045331:Photosystem I Protein Complex; D045332:Photosystem II Protein Complex; D012965:Sodium Chloride; D002701:Chloramphenicol; D004237:Diuron
keywords: Chilling-light; NaCl; PSI; PSII; Photoinhibition