In Mitochondria β-Actin Regulates mtDNA Transcription and Is Required for Mitochondrial Quality Control

摘要: Summary In eukaryotic cells, actin regulates both cytoplasmic and nuclear functions. However, whether actin-based structures are present in the mitochondria involved mitochondrial functions has not been investigated. Here, using wild-type β-actin +/+ knockout (KO) β-actin −/− mouse embryonic fibroblasts we show evidence for defect maintaining membrane potential (MMP) β-actin-null cells. MMP defects were associated with impaired DNA (mtDNA) transcription oxidative phosphorylation (OXPHOS) gene expression. Using super-resolution microscopy provided direct on presence of β-actin-containing inside mitochondria. Large aggregates TFAM-stained nucleoids observed bulb-shaped KO suggesting nucleoid segregation without β-actin. The observation that mitochondria-targeted rescued mtDNA suggests an indispensable functional role a pool necessary quality control.