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MCC and PSC, the putative protein import channels of mitochondria

K W Kinnally1, C Muro, M L Campo

  • 1Division of Molecular Medicine, Wadsworth Center, Albany, New York 12201-0509, USA.

Journal of Bioenergetics and Biomembranes
|January 5, 2002
PubMed

Insights

Mitochondria utilize specific channels, the multiple conductance channel (MCC) and peptide-sensitive channel (PSC), for protein import. Evidence supports MCC and PSC as key protein import channels in mitochondrial membranes.

Area of Science:

  • Mitochondrial biology
  • Membrane biophysics
  • Protein transport

Background:

  • Most mitochondrial proteins are synthesized in the cytoplasm and imported.
  • Aqueous channels are crucial for protein translocation across hydrophobic mitochondrial membranes.

Purpose of the Study:

  • To identify and characterize the protein import channels in mitochondrial membranes.
  • To provide evidence supporting the roles of MCC and PSC in mitochondrial protein import.

Main Methods:

  • Electrophysiological studies of mitochondrial membranes.
  • Genetic, biochemical, and biophysical analyses.

Main Results:

  • Identified two high-conductance channels: MCC and PSC.
  • MCC and PSC are proposed as the pores for protein import complexes in the inner and outer mitochondrial membranes, respectively.

Conclusions:

  • MCC and PSC function as the protein import channels of mitochondria.
  • Genetic, biochemical, and biophysical data confirm the roles of MCC and PSC in mitochondrial protein translocation.

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