Glyceraldehyde-3-Phosphate Dehydrogenase Regulates Endothelin-1 Expression by a Novel, Redox-Sensitive Mechanism Involving mRNA Stability

Abstract

The regulation of the synthesis of the endothelial-derived vasoconstrictor endothelin-1 (ET-1) is a complex process encompassing transcriptional as well as mRNA stability mechanisms. We have described recently the existence of a mechanism for the control of ET-1 expression based on the mRNA-destabilizing capacity of specific cytosolic proteins through interaction with AU-rich elements (AREs) present in the 3′ untranslated region of the gene. We now identify glyceraldehyde-3′-phosphate dehydrogenase (GAPDH) as a protein which binds to the AREs and is responsible for the destabilization of the mRNA. Oxidant stress alters the binding of GAPDH to the mRNA and its capacity to modulate ET-1 expression, a phenomenon occurring through specific S glutathionylation of the catalytically active residue Cys 152. Finally, we provide data consistent with a role for GAPDH in mRNA unwinding, yielding this molecule more prone to degradation. In contrast, S-thiolated GAPDH appears unable to modify mRNA unwinding, thus facilitating enhanced stability. Taken together, these results describe a novel, redox-based mechanism regulating mRNA stability and add a new facet to the panoply of GAPDH cellular homeostatic actions.

ACKNOWLEDGMENTS

This work was supported by grants SAF2006-02410 and Consolider CSD-2007-0020, Network of Excellence for the Research on Oxidative Stress in Spain (NEROSS), from Plan Nacional de I+D+I, CARDIOVREP, from Comunidad de Madrid to S.L.; by a grant from the Sociedad Española de Nefrología to S.L.; and by a grant from Fundación de Investigación Médica Mutua Madrileña to F.R.-P. Fernando Rodríguez-Pascual is the holder of a Ramon y Cajal contract from the Ministerio de Educación y Ciencia.

We thank J. Fernando Díaz (Centro de Investigaciones Biológicas, Madrid, Spain) and Magdalena Torres (Universidad Complutense de Madrid, Spain) for their technical assistance.