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Supramolecular architecture of endoplasmic reticulum-plasma membrane contact sites

Rubén Fernández-Busnadiego1

  • 1Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany ruben@biochem.mpg.de.

Biochemical Society Transactions
|April 13, 2016
PubMed

Insights

Endoplasmic reticulum (ER) membrane contact sites (MCS) are crucial for cellular functions like calcium and lipid homeostasis. Understanding their complex molecular structure, especially with cryo-electron tomography (cryo-ET), is key to their functional insights.

Area of Science:

  • Cell Biology
  • Structural Biology
  • Biophysics

Background:

  • Endoplasmic reticulum (ER) forms membrane contact sites (MCS) with other organelles and the plasma membrane (PM).
  • ER-PM MCS are vital for calcium (Ca2+) and lipid homeostasis, and excitation-contraction coupling (ECC) in muscle.
  • Their functional diversity is linked to complex supramolecular assemblies.

Purpose of the Study:

  • To review the current structural knowledge of ER-PM MCS.
  • To highlight the functional implications of their molecular organization.
  • To emphasize the role of cryo-electron tomography (cryo-ET) in this field.

Main Methods:

  • Review of existing literature on ER-PM MCS.
  • Focus on structural data obtained through various microscopy techniques.
  • Emphasis on cryo-electron tomography (cryo-ET) for high-resolution 3D imaging.

Main Results:

  • ER-PM MCS exhibit significant functional and structural diversity.
  • Cooperative phenomena and large supramolecular assemblies are common features.
  • Cryo-ET provides unprecedented molecular resolution of these structures.

Conclusions:

  • Characterizing the supramolecular architecture of ER-PM MCS is critical for understanding their function.
  • Cryo-ET is a powerful tool for elucidating the structural basis of ER-PM MCS.
  • Further structural studies will advance our knowledge of cellular homeostasis and signaling.
Keywords:
OraiSTIMcryo-EMextended-synaptotagminlipid transferryanodine receptor

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