Genetically encoded thiol redox-sensors in the zebrafish model: lessons for embryonic development and regeneration

Abstract

Important roles for reactive oxygen species (ROS) and redox signaling in embryonic development and regenerative processes are increasingly recognized. However, it is difficult to obtain information on spatiotemporal dynamics of ROS production and signaling in vivo. The zebrafish is an excellent model for in vivo bioimaging and possesses a remarkable regenerative capacity upon tissue injury. Here, we review data obtained in this model system with genetically encoded redox-sensors targeting H2O2 and glutathione redox potential. We describe how such observations have prompted insight into regulation and downstream effects of redox alterations during tissue differentiation, morphogenesis and regeneration. We also discuss the properties of the different sensors and their consequences for the interpretation of in vivo imaging results. Finally, we highlight open questions and additional research fields that may benefit from further application of such sensor systems in zebrafish models of development, regeneration and disease.

The tolerance to hypoxia is defined by a time-sensitive response of the gene regulatory network in sea urchin embryos

“…So even if the sea urchin embryos can survive 16 h of hypoxia, they will probably die in longer periods of low oxygen. Furthermore, in other organisms, ROS and hypoxia signaling regulate multiple developmental processes and, in some cases, these processes last throughout embryogenesis, which could make the embryos of these organisms even more sensitive to hypoxia than sea urchin embryos (Breus and Dickmeis, 2020;Coffman and Su, 2019;Cordeiro and Tanaka, 2020). In line with these alarming observations, lab experiments can show distinct and even opposing trends compared with experiments that are carried out in the field, owing to the increased and unexpected complexity of natural sites (Foo et al, 2020).…”

Reactive oxygen species (ROS) constitute an additional player in regulating epithelial development

“…In addition, more probes and sensors for redox signalling are required. These also include genetically encoded probes to analyse temporal changes in ROS production as well as their spatial distribution at the tissue and cellular level during development (reviewed in [18,[107][108][109] ).…”

Microscopic modulation and analysis of islets of Langerhans in living zebrafish larvae

“…Mitochondria are essential to couple glucose metabolism to insulin secretion under normal physiological conditions and play a major role in apoptotic beta cell death [98]. A large panel of different genetically encoded thiol redox sensors, which are available in zebrafish, report the oxidative stress status in mitochondria in real time in vivo [99][100][101]. Since the oxidative stress may also trigger apoptosis, apoptotic sensors are available in zebrafish.…”