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Effect of Overproduction of Mitochondrial Uncoupling Protein 2 on Cos7 Cells: Induction of Senescent-like Morphology and Oncotic Cell Death
- Source :
- Current Aging Science. 9:229-238
- Publication Year :
- 2016
- Publisher :
- Bentham Science Publishers Ltd., 2016.
-
Abstract
- BACKGROUND The maintenance of mitochondrial membrane potential is essential for cell growth and survival. Mitochondrial uncoupling protein 2 plays the most important roles in uncoupling oxidative phosphorylation and decreasing mitochondrial O2- production by regulating the mitochondrial membrane potential. We propose that mouse UCP2 has two glycine-rich motifs, motif 1: EGIRGLWKG (170-178) and a known Walker A-like motif 2: EGPRAFYKG (264-272). These motifs seem to be important for the function of UCP2. OBJECTIVE We investigated the biological effects of overproduced-UCP2 and its physiological consequence in Cos7 cells. METHOD We introduced several amino acid changes in the motif 1. The expression vectors of the green fluorescent protein (GFP)-fused UCP2 and mutant UCP2 were constructed and expressed in Cos7 cells. RESULT The UCP2-GFP-expressed cells significantly down-regulated the mitochondrial membrane potentials and induced the enlarged cell shapes. Next we generated the stably UCP2-GFP-expressed Cos7 cells by selection with the antibiotic Genecitin (G418). Within the first few weeks following G418-selection, the stably UCP2-GFP-expressed cells could not divide well and gradually manifested the irregular and enlarged senescent-like cell morphology. The UCP2/K177E- or UCP2/G174L-expressed cells did not induce the enlarged cell shapes. Hence, UCP2/K177E and UCP2/G174L produced the functional incompetence of the glycine-rich motif 1. The senescent-like cells significantly decreased the mitochondrial membrane potentials and finally died nearly one month. CONCLUSION Overproduction of UCP2 irreversibly reduces the mitochondrial membrane potentials and induces the senescent-like morphology and finally oncotic cell death in Cos7 cells. These changes seem to occur from the irreversible metabolic changes following total loss of cellular ATP.
- Subjects :
- 0301 basic medicine
Pulmonary and Respiratory Medicine
Recombinant Fusion Proteins
Amino Acid Motifs
Cell
Oxidative phosphorylation
Biology
Transfection
Cell morphology
Mitochondrial apoptosis-induced channel
Mice
03 medical and health sciences
Adenosine Triphosphate
Chlorocebus aethiops
medicine
Animals
Humans
Uncoupling Protein 2
Amino Acid Sequence
Inner mitochondrial membrane
Cell Shape
Cellular Senescence
Membrane Potential, Mitochondrial
Cell Death
Cell growth
Mitochondria
Cell biology
030104 developmental biology
medicine.anatomical_structure
Amino Acid Substitution
COS Cells
Pediatrics, Perinatology and Child Health
Mutagenesis, Site-Directed
DNAJA3
ATP–ADP translocase
Reactive Oxygen Species
Subjects
Details
- ISSN :
- 18746098
- Volume :
- 9
- Database :
- OpenAIRE
- Journal :
- Current Aging Science
- Accession number :
- edsair.doi.dedup.....1f2584c18b7d1cbdec2e138995470a67