Home
Resources
Publications
A Transverse Tubule NADPH Oxidase Activity Stimulates Calcium Release From Isolated Triads via Ryanodine Receptor Type 1 S -Glutathionylation

A Transverse Tubule NADPH Oxidase Activity Stimulates Calcium Release From Isolated Triads via Ryanodine Receptor Type 1 S -Glutathionylation

Cecilia Hidalgo, Gina Sánchez, Genaro Barrientos, Paula Aracena-Parks

J Biol Chem. 2006 Sep 8;281(36):26473-82.

PMID: 16762927

Abstract:

We report here the presence of an NADPH oxidase (NOX) activity both in intact and in isolated transverse tubules and in triads isolated from mammalian skeletal muscle, as established by immunochemical, enzymatic, and pharmacological criteria. Immunohistochemical determinations with NOX antibodies showed that the gp91(phox) membrane subunit and the cytoplasmic regulatory p47(phox) subunit co-localized in transverse tubules of adult mice fibers with the alpha1s subunit of dihydropyridine receptors. Western blot analysis revealed that isolated triads contained the integral membrane subunits gp91(phox) and p22(phox), which were markedly enriched in isolated transverse tubules but absent from junctional sarcoplasmic reticulum vesicles. Isolated triads and transverse tubules, but not junctional sarcoplasmic reticulum, also contained varying amounts of the cytoplasmic NOX regulatory subunits p47(phox) and p67(phox). NADPH or NADH elicited superoxide anion and hydrogen peroxide generation by isolated triads; both activities were inhibited by NOX inhibitors but not by rotenone. NADH diminished the total thiol content of triads by one-third; catalase or apocynin, a NOX inhibitor, prevented this effect. NADPH enhanced the activity of ryanodine receptor type 1 (RyR1) in triads, measured through [3H]ryanodine binding and calcium release kinetics, and increased significantly RyR1 S-glutathionylation over basal levels. Preincubation with reducing agents or NOX inhibitors abolished the enhancement of RyR1 activity produced by NADPH and prevented NADPH-induced RyR1 S-glutathionylation. We propose that reactive oxygen species generated by the transverse tubule NOX activate via redox modification the neighboring RyR1 Ca2+ release channels. Possible implications of this putative mechanism for skeletal muscle function are discussed.

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
IAR42416627	Anti-phospho-p47 phox (pSer359) antibody produced in rabbit			Price
IAR42416804	Anti-phospho-p47 phox (pSer370) antibody produced in rabbit			Price

As a specialist in analytical chemical Products, Alfa Chemistry offers consumers a wealth of raw materials and a full range of technologies and services.

QUICK LINKS

HEADQUARTERS

Tel:

Fax:

Email: