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Updated: Mar 24, 2026

Monitoring Stub1-Mediated Pexophagy
Published on: May 12, 2023
Transit of H2O2 across the endoplasmic reticulum membrane is not sluggish
Christian Appenzeller-Herzog1, Gabor Bánhegyi2, Ivan Bogeski3
1Berufsfachschule Gesundheit Baselland, 4142 Münchenstein, Switzerland.
Abstract:
Cellular metabolism provides various sources of hydrogen peroxide (H2O2) in different organelles and compartments. The suitability of H2O2 as an intracellular signaling molecule therefore also depends on its ability to pass cellular membranes. The propensity of the membranous boundary of the endoplasmic reticulum (ER) to let pass H2O2 has been discussed controversially. In this essay, we challenge the recent proposal that the ER membrane constitutes a simple barrier for H2O2 diffusion and support earlier data showing that (i) ample H2O2 permeability of the ER membrane is a prerequisite for signal transduction, (ii) aquaporin channels are crucially involved in the facilitation of H2O2 permeation, and (iii) a proper experimental framework not prone to artifacts is necessary to further unravel the role of H2O2 permeation in signal transduction and organelle biology.
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