Proteomic and metabolic impacts of the lack of 2-oxoglutarate dehydrogenase E1 subunit in Arabidopsis thaliana

• Ano de defesa: 2022
• Autor(a) principal: Vargas, Jonas Rafael
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Universidade Federal de Viçosa
• Palavras-chave em Português: Enzimas; Plantas - Metabolismo; Stress (Fisiologia); 2-oxoglutarato desidrogenase; Fisiologia Vegetal
• Link de acesso: https://locus.ufv.br//handle/123456789/30005; https://doi.org/10.47328/ufvbbt.2022.451

The enzyme 2-oxoglutarate dehydrogenase (2OGDH) is a tricarboxylic acid cycle enzyme. This enzyme is a multi-enzymatic complex formed by three subunits that together are responsible for catalyzing the conversion of 2-oxoglutarate (2OG) into succinyl-CoA with the release of NADH and CO 2 in the mitochondrial matrix. This enzyme is described as an important point of regulation and link between the metabolism of carbon and nitrogen since in its absence, important processes in the plant such as respiration, photosynthesis and nitrogen assimilation are altered. One way this enzyme exerts control over the metabolism is through the control in the levels of its substrate, 2OG, that is also used for the synthesis of amino acids in the chloroplast. In addition, 2OG plays a role in cell signaling and expression regulation through PII proteins and the 2-oxoglutarate-dependent dioxygenases. In order to help elucidate responses associated with the lack of specific subunits of 2OGDH complex, we set out to analyze the impact caused by the lack of the E1 subunit of the 2OGDH enzyme on the proteome of plants grown under control conditions and also approach the contributions of this enzyme in the response of plants to imposition and recovery of abiotic stress. As a result, we observed that the lack of the E1 subunit of the 2OGDH enzyme is related to a reduction in photosynthetic and photorespiratory metabolisms proteins that may explain the large growth reductions observed in the mutant plants. We also observed that during the period of stress and recovery, the lack of the E1 subunit has a greater impact on the metabolism of roots that respond more quickly to stress, where alternative pathways such as GABA shunt can be activated in order to overcome the lack of this enzyme, and during recovery carbon metabolism is prioritized over nitrogen in the roots. Keywords: 2-oxoglutarate dehydrogenase. Proteome. Abiotic stress. Respiration. Arabidopsis