Redox regulation at the site of primary growth: auxin, cytokinin and ROS crosstalk

Abstract

To maintain the activity of meristems is an absolute requirement for plant growth and development, and the role of the plant hormones auxin and cytokinin in apical meristem function is well established. Only little attention has been given, however, to the function of the reactive oxygen species (ROS) gradient along meristematic tissues and its interplay with hormonal regulatory networks. The interdependency between auxin-related, cytokinin-related and ROS-related circuits controls primary growth and development while modulating plant morphology in response to detrimental environmental factors. Because ROS interaction with redoxactive compounds significantly affects the cellular redox gradient, the latter constitutes an interface for crosstalk between hormone and ROS signalling pathways. This review focuses on the mechanisms underlying ROS-dependent interactions with redox and hormonal components in shoot and root apical meristems which are crucial for meristems maintenance when plants are exposed to environmental hardships. We also emphasize the importance of cell type and the subcellular compartmentalization of ROS and redox networks to obtain a holistic understanding of how apical meristems adapt to stress.

Photoperiod stress alters the cellular redox status and is associated with an increased peroxidase and decreased catalase activity

“…Cytokinin and the circadian clock are required to counteract the oxidative stress caused by 366 photoperiod stress 367 Photoperiod stress clearly occurs in WT but the response to it was much stronger in CK-368 deficient plants (Nitschke et al, 2016;this work). The stronger downregulation of catalase maintenance of meristems in response to stress (Tognetti et al, 2017). However, only little is 375 known about the signaling pathways linking CK and oxidative stress.…”

Cryptotanshinone Attenuates Oxidative Stress and Inflammation through the Regulation of Nrf‐2 and NF‐κB in Mice with Unilateral Ureteral Obstruction

“…If the injuries are sustained, these non‐resolving inflammatory responses set up a fibrogenic local microenvironment and facilitate the activation of matrix‐producing myofibroblasts . In addition, the overproduction of ROS may suppress the activities of the antioxidant molecules, including catalase (CAT), superoxide dismutase (SOD) and glutathione (GSH) . In turn, ROS may expand oxidative stress and enhance inflammation by activating redox‐sensitive pro‐inflammatory transcription factors .…”

Quantitative proteomic analysis of auxin signaling during seedling development

“…Quantitative measurements in protein abundance are critical for elucidating what metabolic changes are driven by auxin ( Figure 4). Interactions between redox and auxin have recently been considered to be critical for meristem activity (Tognetti et al, 2012(Tognetti et al, , 2017. However, proteins associated with redox were differentially regulated in hypocotyls, roots and seedlings in response to auxin suggesting that alteration of redox state may be a common rapid signaling mechanism that follows early auxin response irrespective of spatial context.…”