ROS and NADPH oxidases: new players in the control of Xenopus retinal stem cell proliferation.
Awakening adult neural stem cells: NOX signalling as a positive regulator of quiescence to proliferation transition in the Xenopus retina. Reactive oxygen species (ROS) are mainly produced through the mitochondrial electron transport chain or the activity of NADPH oxidase (NOX) complexes. At basal levels, these molecules constitute essential modulators of cell behaviors. In particular, ROS signalling emerged as an intrinsic regulatory mechanism for adult and embryonic stem cell self-renewal, proliferation and differentiation. However, how stem cells maintain their redox homeostasis, and how ROS in turn control stem cell activity remain poorly understood. In addition, ROS function in stem cell biology is rarely addressed in vivo. To investigate these questions, a team from Neuroscience Paris-Saclay Institute (NeuroPSI) took advantage of the Xenopus retina as a model system. Like fish, but unlike mammals, amphibians possess active retinal stem cells (RSCs) allowing for tissue growth and regeneration all along the animal life.
The team discovered that these cells are endowed with a peculiar redox status: they exhibit higher ROS levels compared to retinal progenitors and neurons, and they express a specific set of antioxidant genes. Functional investigations, using both pharmacological and genetic tools, further revealed that NOX signalling takes central stage in preventing RSC quiescence, through the modulation of the Wnt/Hedgehog signalling balance. Altogether, this study highlights NOX as a novel player of the regulatory network that controls adult neural stem cell proliferative activity within the retina.
Awakening adult neural stem cells: NOX signalling as a positive regulator of quiescence to proliferation transition in the Xenopus retina. Alicia Donval, Cinthia Violeta Hernandez Puente, Anaïs Lainé, Diana Roman, Romain Vessely, Julien Leclercq, Muriel Perron, Morgane Locker
Article published in Development – Access to the manuscript
