Role of peroxisome in mitochondrial dynamics during aging in Drosophila melanogaster
Authors: Ankur Kumar; Pham Vo; Peiduo Liu; Hua Bai
Affiliation: Iowa State University
Keywords: h. mitochondria; n. peroxisomomes
Damaged mitochondria are repaired and recycled through the mechanisms of mitochondrial dynamics in response to stress; this helps in restoring cellular homeostasis. Mitochondrial dynamics have emerged as a novel regulator of aging in recent years. During aging, alterations in mitochondrial morphology and structure have been observed. Researchers have performed genetic manipulations of genes involved in the fission and fusion of mitochondria, which extended the lifespan. However, the causes of the age-dependent alteration in mitochondrial dynamics remain unanswered. Our focus is to explore the involvement of the peroxisome in maintaining mitochondrial homeostasis during animal aging. Recent studies in our lab have shown mitochondrial morphology and function alteration due to impaired peroxisomal protein import in aging oenocytes (hepatocytes) of fruit flies. We found an increase in mitochondrial size in oenocytes during fly aging. Similarly, we have found that the knockdown of Pex5, a peroxisomal import protein, alters mitochondrial morphology. Interestingly, we also have found that peroxisomal plasmalogen level decreases in aging flies, and knocking down the genes involved in peroxisomal plasmalogen synthesis, such as GNPAT (Glyceronephosphate O-acyltransferase) resulted in enlarged mitochondria. Alterations in other peroxisomal genes also have changed the mitochondrial morphology. Thus, our future goal is to understand how peroxisomes contribute to age-related alterations of mitochondrial dynamics and functions.