Dissecting Mitochondrial Redox-Regulated Protein Translocation Using Small Molecule Probes
Mitochondria are responsible for a multitude of cellular functions that almost always require nuclear encoded proteins to be translocated. Defects in mitochondrial import pathways result in many devastating diseases including neurodegeneration, stroke, cardiac ischemia, and cancer. More specifically, mutations of the intermembrane space (IMS) import component DDP1/Tim8 lead to deafness-dystonia syndrome, mutations in the sulfhydryl-oxidase Erv1 result in inherited cardiomyopathy, and mutations in CHCHD10 leads to ALS. Therapies to treat such diseases are not readily available. The development of tools to characterize key components of mitochondrial import pathways is necessary to understand the mechanism of the defects, thus improving therapeutic development.
A collection of small molecules that inhibit Erv1 oxidase activity were identified in a high-throughput chemical screen. Leading candidates were characterized using a battery of biochemical approaches in yeast, zebrafish, and mammalian systems. Moreover, these small molecules have been used to characterize the mechanism of the disulfide relay in mitochondria, dissect novel roles of Erv1/ALR and Mia40, and to investigate how defects in this redox pathway contribute to diseases.