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Assessment of Open Probability of the Mitochondrial Permeability Transition Pore in the Setting of Coenzyme Q Excess
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Assessment of Open Probability of the Mitochondrial Permeability Transition Pore in the Setting of Coenzyme Q Excess

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Inorganic polyphosphate (polyP) as an activator and structural component of the mitochondrial permeability transition

Maria E Solesio1, Pia A Elustondo2, Eleonora Zakharian3

  • 1Department of Basic Sciences, New York University College of Dentistry, 345 East 24 Street, 10010, New York, NY, U.S.A.

Biochemical Society Transactions
|February 11, 2016
PubMed

Insights

The mitochondrial permeability transition pore (mPTP) structure is unclear. Inorganic polyphosphate (polyP) may form the pore, explaining its calcium activation and voltage dependence in cell death.

Area of Science:

  • Mitochondrial biology
  • Cellular physiology
  • Biochemistry

Background:

  • The mitochondrial permeability transition pore (mPTP) is a channel in the inner mitochondrial membrane.
  • mPTP opening causes membrane depolarization, disrupts ATP production, and is key in stress-induced cell death.
  • mPTP is a large complex, with mitochondrial ATPase implicated in its formation, but the pore structure (mPTPore) is unknown.

Purpose of the Study:

  • To review current models of the mPTP pore structure (mPTPore).
  • To discuss the role of inorganic polyphosphate (polyP) in mPTP formation and regulation.
  • To propose a hypothesis on polyP's role in mPTP pore structure and function.

Main Methods:

  • Literature review of existing models and studies on mPTP and polyP.
  • Analysis of proposed mechanisms for mPTP pore formation and regulation.
  • Hypothesis generation based on current evidence.

Main Results:

  • Current models of mPTP pore structure are incomplete.
  • Inorganic polyphosphate (polyP) is proposed as a key component and regulator of the mPTP pore.
  • PolyP's involvement could explain mPTP's calcium activation, ion selectivity, and voltage dependence.

Conclusions:

  • The precise structure of the mPTP pore (mPTPore) remains elusive.
  • Inorganic polyphosphate (polyP) is a critical, yet underestimated, factor in mPTP formation and function.
  • A polyP-inclusive model offers a potential explanation for key mPTP properties, advancing our understanding of cell death pathways.
Keywords:
calciuminorganic polyphosphate (polyP)mitochondriapermeability transition

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