Exonuclease action of replicative polymerase gamma drives damage-induced mitochondrial DNA clearance.

IF 6.5 1区生物学 Q1 BIOCHEMISTRY & MOLECULAR BIOLOGY

EMBO Reports Pub Date : 2025-03-01 Epub Date: 2025-01-31 DOI:10.1038/s44319-025-00380-1

Akshaya Seshadri, Anjana Badrinarayanan

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引用次数: 0

Abstract

Mitochondrial DNA (mtDNA) replication is essential for mitochondrial function. This is carried out by a dedicated DNA polymerase gamma, with 5'-3' polymerase and 3'-5' proofreading/ exonuclease activity. Perturbations to either property can have pathological consequences. Predominant sources for replication stress are DNA lesions, such as those induced by oxidative damage. How mtDNA lesions affect the polymerase activity and mtDNA stability in vivo is not fully understood. To address this, we induce mtDNA-specific damage in S. cerevisiae. We observe that mtDNA damage results in significant mtDNA loss. This loss occurs independent of cell cycle progression or cell division, suggesting an active mechanism for damaged mtDNA clearance. We implicate the 3'-5' exonuclease activity of the mtDNA polymerase in this clearance, with rates of loss being affected by cellular dNTP levels. Overall, our findings reveal context-dependent, selective regulation of two critical but opposing functions of polymerase gamma to ensure mitochondrial genome integrity.

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来源期刊

EMBO Reports 生物-生化与分子生物学

CiteScore

11.20

自引率

1.30%

发文量

267

审稿时长

1 months

期刊介绍： EMBO Reports is a scientific journal that specializes in publishing research articles in the fields of molecular biology, cell biology, and developmental biology. The journal is known for its commitment to publishing high-quality, impactful research that provides novel physiological and functional insights. These insights are expected to be supported by robust evidence, with independent lines of inquiry validating the findings. The journal's scope includes both long and short-format papers, catering to different types of research contributions. It values studies that: Communicate major findings: Articles that report significant discoveries or advancements in the understanding of biological processes at the molecular, cellular, and developmental levels. Confirm important findings: Research that validates or supports existing knowledge in the field, reinforcing the reliability of previous studies. Refute prominent claims: Studies that challenge or disprove widely accepted ideas or hypotheses in the biosciences, contributing to the correction and evolution of scientific understanding. Present null data: Papers that report negative results or findings that do not support a particular hypothesis, which are crucial for the scientific process as they help to refine or redirect research efforts. EMBO Reports is dedicated to maintaining high standards of scientific rigor and integrity, ensuring that the research it publishes contributes meaningfully to the advancement of knowledge in the life sciences. By covering a broad spectrum of topics and encouraging the publication of both positive and negative results, the journal plays a vital role in promoting a comprehensive and balanced view of scientific inquiry.