Glutathione-dependent regulation of cell proliferation and root meristem development

Intracellular redox homeostasis is central to the regulation of cellular functions that underpin the control of plant growth and development. Causal links between cellular redox state, cell proliferation and shoot and root meristem activity have been described but in most cases the underlying mechanisms remain to be characterized. The tripetide thiol reduced glutathione (GSH) is required for cell proliferation and root meristem formation. However, the enzymes and processes that respond to changes in GSH and the redox state of the glutathione pool are poorly characterised. Molecular genetics and pharmacological approaches, in vivo cell staining and redox-sensitive green fluorescent protein (roGFP) techniques were used to explore the redox state of the nucleus and cytoplasm and to identify GSH-responsive genes. Data will be presented concerning the glutathione redox potential of the nucleus and cytoplasm in the root meristem of Arabidopsis thaliana seedlings and how this impacts on the expression of GSH-responsive genes, particularly transcription factors and genes that are involved in the cell proliferation, redox regulation and auxin-mediated processes.