Solute Transport through Mitochondrial Porins In Vitro and In Vivo

Mitochondria are most likely descendants of strictly aerobic prokaryotes from the class <i>Alphaproteobacteria</i>. The mitochondrial matrix is surrounded by two membranes according to its relationship with Gram-negative bacteria. Similar to the bacterial outer membrane, the mitochondria...

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Main Author: Roland Benz
Format: Article
Language:English
Published: MDPI AG 2024-03-01
Series:Biomolecules
Subjects:
Online Access:https://www.mdpi.com/2218-273X/14/3/303
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author Roland Benz
author_facet Roland Benz
author_sort Roland Benz
collection DOAJ
description Mitochondria are most likely descendants of strictly aerobic prokaryotes from the class <i>Alphaproteobacteria</i>. The mitochondrial matrix is surrounded by two membranes according to its relationship with Gram-negative bacteria. Similar to the bacterial outer membrane, the mitochondrial outer membrane acts as a molecular sieve because it also contains diffusion pores. However, it is more actively involved in mitochondrial metabolism because it plays a functional role, whereas the bacterial outer membrane has only passive sieving properties. Mitochondrial porins, also known as eukaryotic porins or voltage-dependent anion-selective channels (VDACs) control the permeability properties of the mitochondrial outer membrane. They contrast with most bacterial porins because they are voltage-dependent. They switch at relatively small transmembrane potentials of 20 to 30 mV in closed states that exhibit different permeability properties than the open state. Whereas the open state is preferentially permeable to anionic metabolites of mitochondrial metabolism, the closed states prefer cationic solutes, in particular, calcium ions. Mitochondrial porins are encoded in the nucleus, synthesized at cytoplasmatic ribosomes, and post-translationally imported through special transport systems into mitochondria. Nineteen beta strands form the beta-barrel cylinders of mitochondrial and related porins. The pores contain in addition an α-helical structure at the N-terminal end of the protein that serves as a gate for the voltage-dependence. Similarly, they bind peripheral proteins that are involved in mitochondrial function and compartment formation. This means that mitochondrial porins are localized in a strategic position to control mitochondrial metabolism. The special features of the role of mitochondrial porins in apoptosis and cancer will also be discussed in this article.
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spelling doaj.art-b6ded77e1f9c4967bd83666ebd6d935d2024-03-27T13:27:54ZengMDPI AGBiomolecules2218-273X2024-03-0114330310.3390/biom14030303Solute Transport through Mitochondrial Porins In Vitro and In VivoRoland Benz0Science Faculty, Constructor University Bremen, Campus-Ring 1, 28759 Bremen, GermanyMitochondria are most likely descendants of strictly aerobic prokaryotes from the class <i>Alphaproteobacteria</i>. The mitochondrial matrix is surrounded by two membranes according to its relationship with Gram-negative bacteria. Similar to the bacterial outer membrane, the mitochondrial outer membrane acts as a molecular sieve because it also contains diffusion pores. However, it is more actively involved in mitochondrial metabolism because it plays a functional role, whereas the bacterial outer membrane has only passive sieving properties. Mitochondrial porins, also known as eukaryotic porins or voltage-dependent anion-selective channels (VDACs) control the permeability properties of the mitochondrial outer membrane. They contrast with most bacterial porins because they are voltage-dependent. They switch at relatively small transmembrane potentials of 20 to 30 mV in closed states that exhibit different permeability properties than the open state. Whereas the open state is preferentially permeable to anionic metabolites of mitochondrial metabolism, the closed states prefer cationic solutes, in particular, calcium ions. Mitochondrial porins are encoded in the nucleus, synthesized at cytoplasmatic ribosomes, and post-translationally imported through special transport systems into mitochondria. Nineteen beta strands form the beta-barrel cylinders of mitochondrial and related porins. The pores contain in addition an α-helical structure at the N-terminal end of the protein that serves as a gate for the voltage-dependence. Similarly, they bind peripheral proteins that are involved in mitochondrial function and compartment formation. This means that mitochondrial porins are localized in a strategic position to control mitochondrial metabolism. The special features of the role of mitochondrial porins in apoptosis and cancer will also be discussed in this article.https://www.mdpi.com/2218-273X/14/3/303mitochondrial porinVDACvoltage dependenceperipheral kinaseslipid bilayerpore structure
spellingShingle Roland Benz
Solute Transport through Mitochondrial Porins In Vitro and In Vivo
Biomolecules
mitochondrial porin
VDAC
voltage dependence
peripheral kinases
lipid bilayer
pore structure
title Solute Transport through Mitochondrial Porins In Vitro and In Vivo
title_full Solute Transport through Mitochondrial Porins In Vitro and In Vivo
title_fullStr Solute Transport through Mitochondrial Porins In Vitro and In Vivo
title_full_unstemmed Solute Transport through Mitochondrial Porins In Vitro and In Vivo
title_short Solute Transport through Mitochondrial Porins In Vitro and In Vivo
title_sort solute transport through mitochondrial porins in vitro and in vivo
topic mitochondrial porin
VDAC
voltage dependence
peripheral kinases
lipid bilayer
pore structure
url https://www.mdpi.com/2218-273X/14/3/303
work_keys_str_mv AT rolandbenz solutetransportthroughmitochondrialporinsinvitroandinvivo