From Biogenesis to Breakdown: How Protein Biogenesis and Quality Control Failures Drive Mitochondrial Disease

Area of Science:

• Mitochondrial biology
• Cellular protein homeostasis
• Molecular medicine

Background:

• Mitochondria utilize over 1000 proteins, primarily synthesized in the cytosol and imported, alongside 13 mitochondrially synthesized proteins crucial for oxidative phosphorylation (OXPHOS).
• Mitochondrial protein maturation, folding, and assembly depend on specialized factors and quality control mechanisms, including chaperones and proteases, to maintain proteome integrity.

Purpose of the Study:

• To highlight the critical role of protein biogenesis and quality control in maintaining mitochondrial function.
• To underscore the need for a comprehensive understanding of these pathways to elucidate disease mechanisms and develop therapeutic strategies.

Main Methods:

• Review and synthesis of current knowledge on mitochondrial protein import, maturation, folding, assembly, and degradation pathways.
• Analysis of the interconnectedness between protein biogenesis and quality control networks within mitochondria.

Main Results:

• Protein biogenesis and quality control are tightly linked, essential for preserving mitochondrial function.
• Dysregulation in any protein processing step can induce proteotoxic stress, leading to mitochondrial dysfunction and disease.

Conclusions:

• Despite significant advancements, substantial knowledge gaps persist regarding mitochondrial protein surveillance mechanisms.
• A complete understanding of mitochondrial proteostasis is fundamental for interpreting genetic mutations, predicting disease progression, and devising targeted therapies for mitochondrial disorders.