Switch from inhibition to activation of the mitochondrial permeability transition during hematoporphyrin-mediated photooxidative stress. Unmasking pore-regulating external thiols

Biochimica Et Biophysica Acta
V PetronilliFernanda Ricchelli


We have studied the mitochondrial permeability transition pore (PTP) under oxidizing conditions with mitochondria-bound hematoporphyrin, which generates reactive oxygen species (mainly singlet oxygen, (1)O(2)) upon UV/visible light-irradiation and promotes the photooxidative modification of vicinal targets. We have characterized the PTP-modulating properties of two major critical sites endowed with different degrees of photosensitivity: (i) the most photovulnerable site comprises critical histidines, whose photomodification by vicinal hematoporphyrin causes a drop in reactivity of matrix-exposed (internal), PTP-regulating cysteines thus stabilizing the pore in a closed conformation; (ii) the most photoresistant site coincides with the binding domains of (external) cysteines sensitive to membrane-impermeant reagents, which are easily unmasked when oxidation of internal cysteines is prevented. Photooxidation of external cysteines promoted by vicinal hematoporphyrin reactivates the PTP after the block caused by histidine photodegradation. Thus, hematoporphyrin-mediated photooxidative stress can either inhibit or activate the mitochondrial permeability transition depending on the site of hematoporphyrin localization and on the natu...Continue Reading


Jul 1, 1979·Proceedings of the National Academy of Sciences of the United States of America·N S KosowerH M Ranney
Apr 15, 1990·Journal of Photochemistry and Photobiology. B, Biology·C Salet, G Moreno
Sep 25, 1998·The Journal of Biological Chemistry·E FontaineP Bernardi
May 30, 2001·Advanced Drug Delivery Reviews·J Morgan, A R Oseroff
Mar 29, 2005·The Journal of Biological Chemistry·Emy BassoPaolo Bernardi
May 10, 2005·The International Journal of Biochemistry & Cell Biology·Fernanda RicchelliValeria Petronilli
May 3, 2006·The FEBS Journal·Paolo BernardiMichael A Forte
Feb 13, 2007·Apoptosis : an International Journal on Programmed Cell Death·Andrea Rasola, Paolo Bernardi
Apr 10, 2007·Nature Cell Biology·Christopher P BainesJeffery D Molkentin
May 19, 2007·Biochimica Et Biophysica Acta·Alessandra ZulianFernanda Ricchelli
Aug 1, 2008·The Journal of Biological Chemistry·Anna W C LeungAndrew P Halestrap

❮ Previous
Next ❯


Nov 3, 2011·The Journal of Membrane Biology·Xiao-Rong LiuYi Liu
Nov 10, 2010·Journal of Bioenergetics and Biomembranes·Tiffany Greco, Gary Fiskum
Oct 1, 2013·Biological Trace Element Research·Jie ZhaoYi Liu
Oct 1, 2013·Asian Pacific Journal of Tropical Biomedicine·Olusola Olalekan ElekofehintiJoao Batista Teixeira Rocha
Sep 21, 2011·Critical Reviews in Food Science and Nutrition·Francesco VisioliMarvin Edeas
Apr 2, 2016·Oxidative Medicine and Cellular Longevity·Nina Kaludercic, Valentina Giorgio
Oct 20, 2009·Biochimica Et Biophysica Acta·Lucia BiasuttoCristina Paradisi
Aug 12, 2016·The Journal of Membrane Biology·Lu LaiYi Liu
May 3, 2014·International Journal of Molecular Sciences·Manuela AntonielGiovanna Lippe
Apr 3, 2014·Physiological Reviews·Ildiko Szabo, Mario Zoratti
Apr 20, 2010·FEBS Letters·Luca AzzolinPaolo Bernardi
Oct 27, 2017·Toxicological Sciences : an Official Journal of the Society of Toxicology·Jia WangYi Liu
Jul 9, 2021·Biometals : an International Journal on the Role of Metal Ions in Biology, Biochemistry, and Medicine·Sergey M Korotkov

❮ Previous
Next ❯

Related Concepts

Trending Feeds


Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.


Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.


Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.