title: Extended survival of SH-SY5Y cells following overexpression of Lys67Glu neuroglobin is associated with stabilization of ΔψM.
abstract: Overwhelming evidence indicates that a high level of expression of the protein neuroglobin protects neurons in vitro, in animal models, and in humans, against cell death associated with hypoxic and amyloid insult. We have previously showed that neuroglobin protects neuronal cells from the mitochondrial pathway of apoptosis induced by the BH3 mimetic, by preventing cytochrome c-triggered activation of caspase 9. Here, using cell and molecular biology approaches, we generated a particular neuroglobin mutant, Lys67Glu, overexpression of which confers a significant protection from the BH3 mimetic (TW-37)-induced apoptosis in human neuroblastoma SH-SY5Y cells. The cumulative inhibition of caspase 9 activation is significantly enhanced in Lys67Glu neuroglobin-expressing cells, as compared to wild-type neuroglobin expressing cells. A multiparameter flow cytometry analysis of TW-37-treated cells revealed that inhibition of caspase 9 activity by Lys67Glu neuroglobin is associated with the preservation of the mitochondrial transmembrane potential (Δψ(M) ), as well as a decreased rate of cytochrome crelease from the mitochondria.
authors.affiliation: School of Biological Sciences, University of Auckland, 3a Symonds Street, Auckland, New Zealand. j.skommer@auckland.ac.nz
authors.forename: Joanna
authors.initials: J
authors.lastname: Skommer
authors.forename: Thomas
authors.initials: T
authors.lastname: Brittain
mesh_terms: D019943:Amino Acid Substitution; D017209:Apoptosis; D001549:Benzamides / Q000494:pharmacology; D053148:Caspase 3 / Q000378:metabolism; D053453:Caspase 9 / Q000378:metabolism; D002460:Cell Line; D002470:Cell Survival; D003198:Computer Simulation; D045304:Cytochromes c / Q000737:chemistry / Q000378:metabolism; D015870:Gene Expression; D005914:Globins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D006801:Humans; D053078:Membrane Potential, Mitochondrial; D051336:Mitochondrial Membranes / Q000378:metabolism; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D009419:Nerve Tissue Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D000078787:Neuroglobin; D010539:Permeability; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000037:antagonists & inhibitors; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D013450:Sulfones / Q000494:pharmacology
chemical_list: D001549:Benzamides; D009419:Nerve Tissue Proteins; D000078787:Neuroglobin; D019253:Proto-Oncogene Proteins c-bcl-2; D011994:Recombinant Proteins; D013450:Sulfones; C515128:TW-37 compound; D005914:Globins; D045304:Cytochromes c; C505407:CASP3 protein, human; C506433:CASP9 protein, human; D053148:Caspase 3; D053453:Caspase 9