Browsing by Author "Uzilday, Baris"

Now showing 1 - 6 of 6

Citation - WoS: 1
Citation - Scopus: 1
Gene expression and mucilage adaptations to salinity in germination of extreme halophyte Schrenkiella parvula seeds
(ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER, 2025-03) Keriman Sekerci; Nahoko Higashitani; Rengin Ozgur; Atsushi Higashitani; Ismail Turkan; Baris Uzilday; Ozgur, Rengin; Şekerci, Keriman; Turkan, Ismail; Higashitani, Nahoko; Higashitani, Atsushi; Uzilday, Baris
Salinization is a significant global issue causes irreversible damage to plants by reducing osmotic potential inhibiting seed germination and impeding water uptake. Seed germination a crucial step towards the seedling stage is regulated by several hormones and genes with the balance between abscisic acid and gibberellin being the key mechanism that either promotes or inhibits this process. Additionally mucilage a gelatinous substance is known to provide protection against drought herbivory soil adhesion and seed sinking. However limited information is available on the structure and thickness of seed mucilage in halophytes under different salinity conditions. In this study the mucilage structure of the extreme halophyte Schrenkiella parvula was compared with the glycophyte Arabidopsis thaliana in response to salinity. We found differences in the expression levels of genes such as ABI5 RGL2 DOG1 ENO2 and DHAR2 which are involved in seed germination and antioxidant activity as well as in the mucilage structure of seeds of S. parvula and A. thaliana seeds at different salt concentrations. The responses of seed germination of S. parvula to salinity indicate that it is more salt-tolerant than A. thaliana. Additionally it was found that S. parvula mucilage decreased under salt conditions but not under mannitol conditions whereas in A. thaliana mucilage did not change under both conditions which is one of the adaptation strategies of S. parvula to salt conditions. We believe that these fundamental analyzes will provide a foundation for future molecular and biochemical studies comparing the responses of crops and halophytes to salinity stress.
Citation - Scopus: 9
Heavy metal toxicity leads to accumulation of insoluble proteins and induces endoplasmic reticulum stress–specific unfolded protein response in Arabidopsis thaliana
(Springer, 2024-08-24) Nil Demircan; Rengin Özgür Uzilday; I. Turkan; B. Uzilday; Ozgur, Rengin; Turkan, Ismail; Uzilday, Baris; Demircan, Nil
Unfolded protein accumulation in the endoplasmic reticulum (ER) triggers ER stress leading to a unique transcriptomic response called unfolded protein response (UPR). While ER stress is linked to various environmental stresses its role in plant responses to heavy metal toxicity remains unclear. This study aimed to elucidate if heavy metals Fe Zn Cu and As induce ER stress in plants. For this purpose Arabidopsis thaliana seedlings were treated with Fe (200 400 µM) Zn (500 700 µM) Cu (25 50 µM) and As (250 500 µM) for 7 days which resulted in 50–70% decrease in plant growth. All treatments increased insoluble protein levels indicating unfolded protein accumulation with the highest induction observed for 50 µM Cu treatment (fivefold). Expressions of genes involved in the perception and signaling of ER stress (IRE1 bZIP28 bZIP60 bZIP17) indicate that Zn toxicity specifically induces bZIP28 but not the IRE1 branch of UPR. All metals except Fe also induced genes associated with protein folding in the ER (BIP1 BIP3 and CNX) and ER-associated protein degradation (ERAD) (HRD1). This finding indicates Zn Cu and As but not Fe cause ER stress in plants. Furthermore increased expression of ER oxidoreductase 1 (ERO1) suggests that metal toxicity also disrupts oxidative protein folding in the ER lumen. This study enhances our understanding of the intricate interplay between essential nutrients metal toxicity protein folding machinery and ER stress demonstrating that heavy metal toxicity has an ER stress component in plants alongside its established effects on energy metabolism membrane integrity and oxidative stress. © 2024 Elsevier B.V. All rights reserved.
Citation - WoS: 9
Citation - Scopus: 11
Role of Abscisic Acid- Reactive Oxygen Species- and Ca2+ Signaling in Hydrotropism-Drought Avoidance-Associated Response of Roots
(MDPI, 2024-04-28) Baris Uzilday; Kaori Takahashi; Akie Kobayashi; Rengin Ozgur Uzilday; Nobuharu Fujii; Hideyuki Takahashi; Ismail Turkan; Fujii, Nobuharu; Uzilday, Baris; Uzilday, Rengin Ozgur; Takahashi, Kaori; Turkan, Ismail; Takahashi, Hideyuki; Kobayashi, Akie
Plant roots exert hydrotropism in response to moisture gradients to avoid drought stress. The regulatory mechanism underlying hydrotropism involves novel regulators such as MIZ1 and GNOM/MIZ2 as well as abscisic acid (ABA) reactive oxygen species (ROS) and Ca2+ signaling. ABA ROS and Ca2+ signaling are also involved in plant responses to drought stress. Although the mechanism of moisture gradient perception remains largely unknown the sensory apparatus has been reported to reside in the root elongation zone rather than in the root cap. In Arabidopsis roots hydrotropism is mediated by the action of MIZ1 and ABA in the cortex of the elongation zone the accumulation of ROS at the root curvature and the variation in the cytosolic Ca2+ concentration in the entire root tip including the root cap and stele of the elongation zone. Moreover root exposure to moisture gradients has been proposed to cause asymmetric ABA distribution or Ca2+ signaling leading to the induction of the hydrotropic response. A comprehensive and detailed analysis of hydrotropism regulators and their signaling network in relation to the tissues required for their function is apparently crucial for understanding the mechanisms unique to root hydrotropism. Here referring to studies on plant responses to drought stress we summarize the recent findings relating to the role of ABA ROS and Ca2+ signaling in hydrotropism discuss their functional sites and plausible networks and raise some questions that need to be answered in future studies.
Citation - Scopus: 4
Roles of Reactive Carbonyl Species (RCS) in Plant Response to Abiotic Stress
(Humana Press Inc., 2024) Mustafa Cemre Sonmez; Side Selin Su Yirmibesoglu; Rengin Özgür Uzilday; B. Uzilday; I. Turkan; Ozgur, Rengin; Turkan, Ismail; Sonmez, Mustafa Cemre; Yirmibesoglu, Side Selin Su; Uzilday, Baris
Abiotic and biotic stress conditions lead to production of reactive carbonyl species (RCS) which are lipid peroxide derivatives and have detrimental effects on plant cells especially at high concentrations. There are several molecules that can be classified in RCS, among them 4-hydroxy-(E)-2-nonenal (HNE) and acrolein are widely recognized and studied because of their toxicity. The toxicity mechanisms of RCS are well known in animals but their roles in plant systems especially signaling aspects in metabolism need to be addressed. This chapter focuses on the production mechanisms of RCS in plants as well as how plants scavenge and modify them to prevent irreversible damage in the cell. We aimed to get a comprehensive look at the literature to summarize the signaling roles of RCS in plant metabolism and their interaction with other signaling mechanisms such as highly recognized reactive oxygen species (ROS) signaling. Changing climate promotes more severe abiotic stress effects on plants which also decrease yield on the field. The effects of abiotic stress conditions on RCS metabolism are also gathered in this chapter including their signaling roles during abiotic stresses. Different methods of measuring RCS in plants are also presented in this chapter to draw more attention to the study of RCS metabolism in plants. © 2024 Elsevier B.V. All rights reserved.
The Interaction between Histone Acetylation and Methylation with ROS Metabolism in Plants
(Springer, 2026-02-03) Ozgur, Rengin; Turkan, Ismail; Sevim, Gulcin; Keskinoglu, Merve; Gumus, B. Ozlem; Uzilday, Baris
Plants are constantly challenged by various abiotic stresses throught their life cycle and have evolved complex defence systems to ensure survival. Reactive oxygen species (ROS) are generated as byproducts of diverse metabolic pathways, acting not only as damaging molecules but also as essential signaling mediators at basal levels. Recent evidence indicates that enzymes involved in ROS/redox metabolism can influence gene expression by modulating histone modifications, particularly acetylation and methylation. Nevertheless, the precise molecular mechanisms linking ROS dynamics to epigenetic regulation remain poorly understood. This review synthesizes current knowledge on the interplay between ROS metabolism and global histone modifications in plants, highlighting how these interactions shape transcriptional reprogramming under stress conditions. Furthermore, we discuss how this crosstalk contributes to plant defence strategies against abiotic stresses such as drought, salinity, and heavy metal exposure, and we identify emerging questions and future research directions in this rapidly developing field.
The Interaction between Histone Acetylation and Methylation with ROS Metabolism in Plants
(Springer, 2026-02-03) Ozgur, Rengin; Turkan, Ismail; Sevim, Gulcin; Keskinoglu, Merve; Gumus, B. Ozlem; Uzilday, Baris
Plants are constantly challenged by various abiotic stresses throught their life cycle and have evolved complex defence systems to ensure survival. Reactive oxygen species (ROS) are generated as byproducts of diverse metabolic pathways, acting not only as damaging molecules but also as essential signaling mediators at basal levels. Recent evidence indicates that enzymes involved in ROS/redox metabolism can influence gene expression by modulating histone modifications, particularly acetylation and methylation. Nevertheless, the precise molecular mechanisms linking ROS dynamics to epigenetic regulation remain poorly understood. This review synthesizes current knowledge on the interplay between ROS metabolism and global histone modifications in plants, highlighting how these interactions shape transcriptional reprogramming under stress conditions. Furthermore, we discuss how this crosstalk contributes to plant defence strategies against abiotic stresses such as drought, salinity, and heavy metal exposure, and we identify emerging questions and future research directions in this rapidly developing field.