Major plasma membrane-associated redox centres co-localize with L-type calcium channels in neuronal lipid rafts microdomains

摘要

Superoxide anion production by redox centers associated with the neuronal plasma membrane can elicit a large peroxynitrite stress, because neuronal nitric oxide syn-thase (nNOS) is associated with the neuronal cytoskeleton within synaptic terminals. In a previous study we showed that L-type calcium channels are highly sensitive to peroxynitrite in cerebellar granule neurons in culture (CGN). In this work, using FRET-imaging we show that nNOS and the enzyme that accounts for most of superoxide anion production at the neuronal plasma membrane (cytochrome b_5 reductase) co-localize with L-type calcium channels within microdomains associated with lipid rafts in mature CGN. Our results strongly suggest that these microdomains play a major role in the cross-talk between redox and calcium signalling in neurons.