Redox regulation of transcription factors in neuroprotection

The electrical activity of neurons generates reactive oxygen species (ROS)
through metabolism but is also intrinsically neuroprotective: neurons neutralize
ROS through activity-dependent expression of antioxidant proteins to maintain
their health. ROS and oxidative damage accumulate during aging such that
neuronal activity-induced antioxidant responses are not sufficient to maintain
optimal neuronal function and neuronal viability, contributing to the pathogenesis
of neurodegenerative disease. It is therefore important to understand how
neurons counter ROS. The signaling pathways linking synaptic activity and
oxidative stress with antioxidant gene expression are not fully understood. We
and others have shown that in response to synaptic activity and elevated ROS,
AP-1 transcription factors (TFs) induce expression of antioxidant genes such as
sulfiredoxin. The activity of these TFs is known to be regulated by
phosphorylation events but they also contain cysteines that are oxidized by
redox signaling pathways. The project will investigate whether neurons use
phosphorylation and cysteine modification of TFs in concert to decode the level
of synaptic activity/and or the oxidative stress burden. The project will in
particular, use novel ways to compartmentalize and restrict the imposed
oxidative stress to neuronal dendrites.
The student will use molecular, cellular and biochemical techniques to
investigate whether phosphorylation is required for cysteine modification and
vice versa. Transcriptional activity of wild-type and phospho-site/cysteine mutant
AP-1 proteins will be measured in real-time in mammalian cell lines and in

primary neurons through the use of bioluminescent reporter genes. A state-of-
the-art microfluidics device will be used to impose oxidative stress specifically in

neuronal dendritic compartments, which are the sites of synaptic activity.