Research on the association between mitochondrial DNA mutations and cellular senescence by mitochondrial base editor

• 1、CAM-SU Genomic Resource Center, Suzhou Medical College of Soochow University, Suzhou 215123

Abstract：As the global population ages, aging and its related diseases are becoming an area of intense research interest. Studies have shown that the accumulation of mutations in mitochondrial genome (mtDNA) is associated with the aging process, but the direct causal link between the two has not been clearly elucidated. Recent advances in mitochondrial base editing tools, such as DdCBE, have enabled In this study, we investigated the relationship between the two using a novel mitochondrial base editing tool, DdCBE, have enabled precise single-nucleotide substitutions in mtDNA, providing powerful means to investigate the relationship between mtDNA mutations and aging. In this study, we designed DdCBE vesctors targeting key genes in mtDNA and successfully generated ND5-mutated HEK293T cell lines. Phenotypic characterization revealed that ND5-mutated cells exhibited obvious senescence phenotypes, including mitochondrial dysfunction, cell cycle arrest, and up-regulation of the senescence-associated secretory phenotype (SASP). These findings demonstrated that single-site mutation in critical mtDNA genes can directly drive cellular senescence, suggesting a direct causal relationship between mtDNA mutations and cellular senescence. This study not only presents a novel research paradigm for investigating mitochondrial-associated aging, but also expands the potential applications of mitchondrial base editing tools.

Keywords： Senescence Mitochondrial genome mtDNA mutation Base editing tools