A new insight to explore the regulation between -nitrosylation and -glycosylation.

Nitric oxide (NO) is a signal molecule in plants and animals. GSNO reductase1 (AtGSNOR1) catalyzes metabolism of -nitrosoglutathione (GSNO) which is a major biologically active NO species. The loss-of-function mutant overaccumulates GSNO with inherent high -nitrosylation level and resistance to the oxidative stress inducer paraquat (1,1'-dimethyl-4,4'-bipyridinium dichloride). Here, we report the characterization of as a genetic suppressor of . encodes a subunit of the oligosaccharyltransferse (OST) complex which catalyzes the formation of -glycosidic bonds in -glycosylation. The fact that repressed the paraquat resistance of meanwhile rescued the embryo-lethal and post-embryonic development defect of reminded us the possibility that -nitrosylation and -glycosylation crosstalk with each other through co-substrates. By enriching glycoproteins in and mass spectrometry analysis, TGG2 (thioglucoside glucohydrolase2) was identified as one of co-substrates with high degradation rate and elevated -glycosylation level in . The -nitrosylation and -glycosylation profiles were also modified in and . Thereby, we propose a linkage between -nitrosylation and -glycosylation through co-substrates.