Background: Although different theories and hypotheses were postulated for aging, molecular mechanisms of its regulations are still vastly unknown. In time, a post-mitotic cell ages with the aggregation of mutations within its genome and reach senescence. The DNA repair system that protects its genome also malfunctions with time. This study aims to discover whether manipulating a DNA repair gene can regulate the cellular life span, especially the chronological life span using the single-cell model (Saccharomyces cerevisiae) in the field of aging. Methods: In this study, yeast mutant that lacks nucleotide excision repair (NER) gene RAD7 along with the diploid wild type (DP-WT) yeast strain (BY4743) as control were used. RAD7 encodes a protein that acts in the NER of UV-damaged DNA. To characterize the mutant cell, experiments i.e. chronological lifespan assay, growth-proliferation, respiration status, mtDNA distribution patterns, and interaction analysis using bioinformatics were conducted. MIPS functional classification using FunSpec software was used to determine RAD7’s interaction with diverse genes.Results: In the chronological lifespan assay, it was found that the RAD7 gene’s null mutation (Δrad7) had a prolonged stationary phase compared to the wild-type strain. The mutant displayed respiration potency by growing well on a glycerol-based medium. Fluorescence microscopic observations disclosed that the mutants had a lower abundance of mtDNA compared to the control. Furthermore, RAD7 gene interaction analysis demonstrated how it interacts with other genes in the organism. Mutation of this repair gene affects mtDNA distribution and mtDNA abundance, yet cells could survive in the chronological phase. MtDNA depletion is a sign of altered mitochondrial morphology and function that may activate a retrograde response from mitochondria to the nucleus. Conclusion: From this study, it is suggested that the RAD7 gene can regulate yeast cells’ life span. However, the retrograde response was not investigated in this current study and thus further efforts are also required to draw a fine conclusion.