The FtsZ Homolog, FszB, Inhibits Mitochondrial Dynamics in Dictyostelium discoideum
Ericka Vogel1, Pristine Bay Pittman1, Kari Naylor1
1Department of Biology, University of Central Arkansas, Conway, AR 72035, USA.
Abstract:
Dictyostelium discoideum is a well-established mitochondrial model system for both disease and dynamics, yet we still do not understand the actual mechanism of mitochondrial dynamics in this system. The FtsZ proteins are known to mediate membrane remodeling events such as cytokinesis in bacteria and fission of chloroplasts; D. discoideum has two FtsZ proteins, FszA and FszB. To determine the role of these proteins in mitochondrial dynamics we overexpressed FszB-GFP and determined its effect on fission, fusion, and motility in the presence of intact and disrupted cytoskeletal filaments. Here we show that overexpression of FszB-GFP decreases mitochondrial dynamics and suggest that actin may play a positive role driving fission in the context of excessive inhibition by overexpressed FszB-GFP.
Insights
Overexpressing FszB-GFP in Dictyostelium discoideum hinders mitochondrial dynamics. Actin may promote mitochondrial fission when FszB-GFP is excessively inhibited, revealing new insights into mitochondrial mechanisms.
Area of Science:
- Cell Biology
- Mitochondrial Biology
- Biochemistry
Background:
- Dictyostelium discoideum is a key model organism for studying mitochondrial dynamics and disease.
- The precise mechanisms governing mitochondrial dynamics in D. discoideum remain largely unknown.
- FtsZ proteins are implicated in membrane remodeling, including bacterial cytokinesis and chloroplast fission.
Purpose of the Study:
- To investigate the role of FszB, an FtsZ protein, in regulating mitochondrial dynamics within D. discoideum.
- To elucidate the impact of FszB overexpression on mitochondrial fission, fusion, and motility.
- To explore the interplay between FszB and the cytoskeleton in controlling mitochondrial behavior.
Main Methods:
- Overexpression of FszB fused with Green Fluorescent Protein (FszB-GFP) in D. discoideum.
- Analysis of mitochondrial fission, fusion, and motility under conditions of intact and disrupted cytoskeletal filaments.
- Microscopic observation and quantification of mitochondrial dynamics.
Main Results:
- Overexpression of FszB-GFP significantly reduced overall mitochondrial dynamics.
- Evidence suggests that actin filaments play a positive role in driving mitochondrial fission.
- This effect was observed particularly under conditions of excessive inhibition by overexpressed FszB-GFP.
Conclusions:
- FszB is a key regulator of mitochondrial dynamics in D. discoideum.
- Actin cytoskeleton is implicated in promoting mitochondrial fission, especially when FszB function is perturbed.
- Findings provide novel insights into the molecular mechanisms of mitochondrial dynamics in this model system.
