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PubMed · 7851527

Self-aggregation of purified and membrane-bound erythrocyte CD38 induces extensive decrease of its ADP-ribosyl cyclase activity.

E Zocchi·L Franco·L Guida·L Calder·A De Flora
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Abstract

The transmembrane glycoprotein CD38 is a bifunctional enzyme that catalyzes at its ectocellular domain both the synthesis and the hydrolysis of cyclic ADP-ribose (cADPR). The complete reaction, converting NAD+ to nicotinamide and ADP-ribose, reproduces an NAD+glycohydrolase (NADase) reaction. CD38 purified from human erythrocyte membranes has been recently shown to undergo stable oligomerization induced by either NAD+ or beta-mercaptoethanol. We demonstrate that oligomerization is also triggered by reduced glutathione (GSH) and that the GSH-induced self-aggregation of purified CD38 is accompanied by extensive and comparable decrease of its ADP-ribosyl cyclase and NADase activities. GSH-induced oligomerization of CD38 and strong enzyme inactivation take place also in situ on erythrocyte membranes.

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ADP-ribosyl CyclaseADP-ribosyl Cyclase 1Adenosine Diphosphate RiboseAntigens, CDAntigens, DifferentiationErythrocyte MembraneGlutathioneHumansMacromolecular SubstancesMembrane GlycoproteinsMercaptoethanolN-Glycosyl HydrolasesNADJournal ArticleResearch Support, Non-U.S. Gov't

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E Zocchi, L Franco, L Guida, L Calder, A De Flora. 1995-02-06. Self-aggregation of purified and membrane-bound erythrocyte CD38 induces extensive decrease of its ADP-ribosyl cyclase activity.. https://doi.org/10.1016/0014-5793(95)00005-t

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ADP-ribosyl Cyclase↗