Anchored FRET sensors detect local caspase activation prior to neuronal degeneration

Detection of Caspase-3-like Proteases Activation Using FRET

ERK activation promotes neuronal degeneration predominantly through plasma membrane damage and independently of caspase-3

Our recent studies have shown that extracellular-regulated protein kinase (ERK) promotes cell death in cerebellar granule neurons (CGN) cultured in low potassium. Here we report that the "death" phenotypes of CGN after potassium withdrawal are heterogeneous, allowing the distinction between plasma membrane (PM)-, DNA-, and PM/DNA-damaged populations. These damaged neurons display nuclear conden...

Contribution of p53-dependent caspase activation to neuronal cell death declines with neuronal maturation.

Caspases play a pivotal role in neuronal cell death during development and after trophic factor withdrawal. However, the mechanisms regulating caspase activity and the role played by caspase activation in response to neuronal injury is poorly understood. The tumor suppressor gene p53 has been implicated in the loss of neuronal viability caused by excitotoxic and DNA damaging agents. In the pres...

Engineering Genetically Encoded FRET Sensors

Förster Resonance Energy Transfer (FRET) between two fluorescent proteins can be exploited to create fully genetically encoded and thus subcellularly targetable sensors. FRET sensors report changes in energy transfer between a donor and an acceptor fluorescent protein that occur when an attached sensor domain undergoes a change in conformation in response to ligand binding. The design of sensit...

Energy requirement for caspase activation and neuronal cell death.

Recent work has shown that execution of the apoptotic program involves a relatively limited number of pathways. According to a general view, these would converge to activate the caspase family of proteases. However, there is increasing evidence that apoptotic-like features can be found also when cells are treated with inhibitors of caspases as the cell permeable tripeptide, Z-Val-Ala-Asp-fluoro...