Yeast mitochondria contain ATP-sensitive, reversible actin-binding activity

Mol Biol Cell. 1994 Jul;5(7):807-18. doi: 10.1091/mbc.5.7.807.

Abstract

Sedimentation assays were used to demonstrate and characterize binding of isolated yeast mitochondria to phalloidin-stabilized yeast F-actin. These actin-mitochondrial interactions are ATP sensitive, saturable, reversible, and do not depend upon mitochondrial membrane potential. Protease digestion of mitochondrial outer membrane proteins or saturation of myosin-binding sites on F-actin with the S1 subfragment of skeletal myosin block binding. These observations indicate that a protein (or proteins) on the mitochondrial surface mediates ATP-sensitive, reversible binding of mitochondria to the lateral surface of microfilaments. Actin copurifies with mitochondria during subcellular fractionation and is released from the organelle upon treatment with ATP. Thus, actin-mitochondrial interactions resembling those observed in vitro may also exist in intact yeast cells. Finally, a yeast mutant bearing a temperature-sensitive mutation in the actin-encoding ACT1 gene (act1-3) displays temperature-dependent defects in transfer of mitochondria from mother cells to newly developed buds during yeast cell mitosis.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Actins / genetics
  • Actins / metabolism*
  • Adenosine Triphosphate / pharmacology*
  • Fungal Proteins / metabolism*
  • Microfilament Proteins / genetics
  • Microfilament Proteins / metabolism*
  • Mitochondria / metabolism*
  • Myosins / metabolism
  • Point Mutation
  • Protein Binding / drug effects
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Ultracentrifugation

Substances

  • Actins
  • Fungal Proteins
  • Microfilament Proteins
  • Adenosine Triphosphate
  • Myosins