Mitochondrial DNA: cellular genotoxic stress sentinel.

Area of Science:

• Mitochondrial biology
• Genetics
• Cellular stress response

Background:

• Mitochondrial DNA (mtDNA) is essential for oxidative phosphorylation but possesses unique features like high copy number and damage proneness.
• The role of mtDNA beyond energy production remains incompletely understood.

Purpose of the Study:

• To propose and discuss evidence for mitochondrial DNA (mtDNA) functioning as a genotoxic stress sentinel and second messenger.
• To explore the implications of mtDNA's role in cellular stress signaling.

Main Methods:

• Review and synthesis of existing evidence.
• Discussion of mtDNA's ability to exit the mitochondrial matrix.
• Analysis of downstream signaling pathways involving interferon-stimulated genes.

Main Results:

• Mitochondrial DNA (mtDNA) can escape the mitochondrial matrix to activate nuclear DNA damage and repair responses.
• This signaling involves interferon-stimulated gene products and other downstream effectors.

Conclusions:

• Mitochondrial DNA (mtDNA) serves a dual role as an energy producer and a genotoxic stress sentinel.
• This sentinel function may contribute to cancer chemoresistance, inflammation, disease pathology, and aging.