Enhancement by GOSPEL protein of GAPDH aggregation induced by nitric oxide donor and its inhibition by NAD⁺

Abstract

Edited by Barry HalliwellGlyceraldehyde-3-phosphate dehydrogenase's (GAPDH's) competitor of Siah Protein Enhances Life (GOSPEL) is the protein that competes with Siah1 for binding to GAPDH under NO-induced stress conditions preventing Siah1-bound GAPDH nuclear translocation and subsequent apoptosis. Under these conditions, GAPDH may also form amyloid-like aggregates proposed to be involved in cell death. Here, we report the in vitro enhancement by GOSPEL of NO-induced GAPDH aggregation resulting in the formation GOSPEL-GAPDH co-aggregates with some amyloid-like properties. Our findings suggest a new function for GOSPEL, contrasting with its helpful role against the apoptotic nuclear translocation of GAPDH. NAD + inhibited both GAPDH aggregation and co-aggregation with GOSPEL, a hitherto undescribed effect of the coenzyme against the consequences of oxidative stress.

Modification of Glyceraldehyde-3-Phosphate Dehydrogenase with Nitric Oxide: Role in Signal Transduction and Development of Apoptosis

“…This hypothesis was not developed further. Moreover, it was shown that GOSPEL stimulates the formation of amyloid aggregates induced by the S -nitrosylation of GAPDH [ 55 ]. Then, one more mechanism of signal transduction mediated by S -nitrosylated GAPDH was proposed, according to which the nitric oxide group is transferred from S -nitrosylated GAPDH to nuclear proteins, including the deacetylating enzyme sirtuin-1 (SIRT1), histone deacetylase-2 (HDAC2), and DNA-activated protein kinase (DNA-PK) [ 56 ].…”

Characterization of human triosephosphate isomerase S-nitrosylation

“…hTPI activity was measured in the direction of DHAP conversion to G3P. The reaction was coupled to purified recombinant hGAPDH [35] under conditions in which the overall reaction was limited by the isomerase reaction. The increase in the absorbance at 340 nm, due to the formation of NADH (extinction coefficient = 6220 M −1 cm −1 ), was monitored at 30 °C using a Shimadzu UV-PC 1600 spectrophotometer equipped with a Peltier control of temperature.…”