title: Senescence, Stress, and Reactive Oxygen Species.
abstract: Generation of reactive oxygen species (ROS) is one of the earliest responses of plant cells to various biotic and abiotic stresses. ROS are capable of inducing cellular damage by oxidation of proteins, inactivation of enzymes, alterations in the gene expression, and decomposition of biomembranes. On the other hand, they also have a signaling role and changes in production of ROS can act as signals that change the transcription of genes that favor the acclimation of plants to abiotic stresses. Among the ROS, it is believed that H₂O₂ causes the largest changes in the levels of gene expression in plants. A wide range of plant responses has been found to be triggered by H₂O₂ such as acclimation to drought, photooxidative stress, and induction of senescence. Our knowledge on signaling roles of singlet oxygen (¹O₂) has been limited by its short lifetime, but recent experiments with a flu mutant demonstrated that singlet oxygen does not act primarily as a toxin but rather as a signal that activates several stress-response pathways. In this review we summarize the latest progress on the signaling roles of ROS during senescence and abiotic stresses and we give a short overview of the methods that can be used for their assessment.
authors.affiliation: Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University in Krakow, Gronostajowa 7, Krakow 30-387, Poland. ivan.jajic1705@gmail.com.
authors.forename: Ivan
authors.initials: I
authors.lastname: Jajic
authors.affiliation: Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University in Krakow, Gronostajowa 7, Krakow 30-387, Poland. tadeusz.sarna@uj.edu.pl.
authors.forename: Tadeusz
authors.initials: T
authors.lastname: Sarna
authors.affiliation: Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University in Krakow, Gronostajowa 7, Krakow 30-387, Poland. kazimierzstrzalka@gmail.com.|Malopolska Centre of Biotechnology, Jagiellonian University in Krakow, Gronostajowa 7, Krakow 30-387, Poland. kazimierzstrzalka@gmail.com.
authors.forename: Kazimierz
authors.initials: K
authors.lastname: Strzalka
keywords: abiotic stresses; hydrogen peroxide; leaf senescence; reactive oxygen species; singlet oxygen; superoxide anion