Polyamines reprogram oxidative and nitrosative status and the proteome of citrus plants exposed to salinity stress
Journal
Plant, Cell and Environment
Date Issued
April 2014
DOI
10.1111/pce.12204
Abstract
The interplay among polyamines (PAs) and reactive oxygen and nitrogen species (RNS and ROS) is emerging as a key issue in plant responses to salinity. To address this question, we analysed the impact of exogenous PAs [putrescine (Put), spermidine (Spd) and spermine (Spm)] on the oxidative and nitrosative status in citrus plants exposed to salinity. PAs partially reversed the NaCl-induced phenotypic and physiological disturbances. The expression of PA biosynthesis (ADC, SAMDC, SPDS and SPMS) and catabolism (DAO and PAO) genes was systematically up-regulated by PAs. In addition, PAs altered the oxidative status in salt-stressed plants as inferred by changes in ROS production and redox status accompanied by regulation of transcript expression and activities of various antioxidant enzymes. Furthermore, NaCl-induced up-regulation of NO-associated genes, such as NR, NADde, NOS-like and AOX, along with S-nitrosoglutathione reductase and nitrate reductase activities, was partially restored by PAs. Protein carbonylation and tyrosine nitration are depressed by specific PAs whereas protein S-nitrosylation was elicited by all PAs. Furthermore, we identified 271 S-nitrosylated proteins that were commonly or preferentially targeted by salinity and individual PAs. This work helps improve our knowledge on the plant's response to environmental challenge.