Altered plant and nodule development and protein S-nitrosylation in Lotus japonicus mutants deficient in S-nitrosoglutathione reductases

Author(s)
Manuel A Matamoros, Maria C Cutrona, Stefanie Wienkoop, Juan C Begara-Morales, Niels Sandal, Irene Orera, Juan B Barroso, Jens Stougaard, Manuel Becana
Abstract

Nitric oxide (NO) is a crucial signaling molecule that conveys its bioactivity mainly through protein S-nitrosylation. This is a reversible post-translational modification (PTM) that may affect protein function. S-nitrosoglutathione (GSNO) is a cellular NO reservoir and NO donor in protein S-nitrosylation. The enzyme S-nitrosoglutathione reductase (GSNOR) degrades GSNO, thereby regulating indirectly signaling cascades associated to this PTM. Here the two GSNORs of the legume Lotus japonicus, LjGSNOR1 and LjGSNOR2, have been functionally characterized. The LjGSNOR1 gene is very active in leaves and roots, whereas LjGSNOR2 is highly expressed in nodules. The enzyme activities are regulated in vitro by redox-based PTMs. Reducing conditions and hydrogen sulfide-mediated cysteine persulfidation induced both activities, whereas cysteine oxidation or glutathionylation inhibited them. Ljgsnor1 knockout mutants contained higher levels of S-nitrosothiols. Affinity chromatography and subsequent shotgun proteomics allowed us to identify 19 proteins that are differentially S-nitrosylated in the mutant and the wild-type. These include proteins involved in biotic stress, protein degradation, antioxidant protection and photosynthesis. We propose that, in the mutant plants, deregulated protein S-nitrosylation contributes to developmental alterations, such as growth inhibition, impaired nodulation and delayed flowering and fruiting. Our results highlight the importance of GSNOR function in legume biology.

Organisation(s)
Department of Ecogenomics and Systems Biology
External organisation(s)
Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Jaén, Aarhus University, Health Sciences Institute in Aragon
Journal
Plant and Cell Physiology
Volume
61
Pages
105 - 117
ISSN
0032-0781
DOI
https://doi.org/10.1093/pcp/pcz182
Publication date
09-2019
Peer reviewed
Yes
Austrian Fields of Science 2012
Plant physiology, Proteomics, Biochemistry
Keywords
Portal url
https://ucris.univie.ac.at/portal/en/publications/altered-plant-and-nodule-development-and-protein-snitrosylation-in-lotus-japonicus-mutants-deficient-in-snitrosoglutathione-reductases(5d7e381d-dc75-44a9-9f32-1f42525b35a4).html