Mitochondrial Spare Respiratory Capacity Is Negatively Correlated with Nuclear Reprogramming Efficiency

Area of Science:

• Cell Biology
• Metabolic Reprogramming
• Stem Cell Research

Background:

• Nuclear reprogramming efficiency into induced pluripotent stem cells (iPSCs) is variable and not fully understood.
• Fibroblast reprogramming involves mitochondrial remodeling and a metabolic shift towards glycolysis.
• Mitochondrial function is implicated in the efficiency of somatic cell reprogramming.

Purpose of the Study:

• To investigate the relationship between fibroblast mitochondrial bioenergetic parameters and nuclear reprogramming efficiency.
• To determine if mitochondrial spare respiratory capacity (SRC) can predict reprogramming outcomes.
• To assess the impact of gene editing on mitochondrial function and reprogramming efficiency.

Main Methods:

• Utilized Seahorse extracellular energy flux analyzer to measure oxygen consumption rate (OCR) in human fibroblasts.
• Quantified nuclear reprogramming efficiency into iPSCs from seven different individuals.
• Employed CRISPR/Cas9-mediated homologous recombination for targeted gene tagging (MYH6, COL2A1).

Main Results:

• Fibroblasts with lower mitochondrial SRC exhibited higher reprogramming efficiency.
• Fibroblasts with higher mitochondrial SRC showed lower reprogramming efficiency.
• CRISPR/Cas9 gene editing increased SRC and impaired reprogramming efficiency.

Conclusions:

• A negative correlation exists between high mitochondrial SRC in somatic cells and reprogramming efficiency.
• Mitochondrial SRC can potentially be used to screen and predict reprogramming efficiency.
• Strategies targeting mitochondrial SRC modulation may enhance nuclear reprogramming.