Physiological and Proteomic Analysis Revealed the Response Mechanisms of two Different Grought-resistant Maize Varieties

Abstract

Background: Drought stress seriously limits the seedling growth and yield of maize. Despite previous studies on drought resistance mechanisms by which maize cope with water deficient, the link between physiological and molecular variations are largely unknown. To reveal the complex regulatory mechanisms, comparative physiology and proteomic analyses were conducted to investigate the stress responses of two maize cultivars with contrasting tolerance to drought stress. Results: Physiological results showed that SD609 (drought-tolerant) maintains higher photochemical efficiency by enhancing CEF (cyclic electron flow) protective mechanism and antioxidative enzymes activities. Proteomics analysis revealed a total of 198 and 102 proteins were differentially expressed in SD609 and SD902, respectively. Further enrichment analysis indicated that drought-tolerant ‘SD609’ increased the expression of proteins related to photosynthesis, antioxidants/detoxifying enzymes, molecular chaperones and metabolic enzymes. The up-regulation proteins related to PSII repair and photoprotection mechanisms resulted in more efficient photochemical capacity in tolerant variety under moderate drought. However, the drought-sensitive ‘SD902’ only induced molecular chaperones and sucrose synthesis pathways, and failed to protect the impaired photosystem. Further analysis indicated that proteins related to the electron transport chain, redox homeostasis and heat shock proteins (HSPs) could be important in protecting plants from drought stress. Conclusions: Our experiments explored the mechanism of drought tolerance, and obtained detailed information about the interconnection of physiological research and protein research. In summary, our findings could provide new clues into further understanding of drought tolerance mechanisms in maize.

Respostas enzimáticas da cana-de-açúcar em área de sequeiro

“…As EROs são formas reduzidas de oxigênio atmosférico e estão presentes na maioria dos sistemas biológicos, sua ocorrência verifica-se de forma natural em grande parte das células eucarióticas porque o metabolismo energético é dependente do uso de oxigênio secundário, provenientes da fotossíntese e da respiração (Foyer, 2018). A exposição das plantas a condições ambientais desfavoráveis aumenta a produção de espécies reativas de oxigênio, causando danos em compartimentos celulares (Li et al, 2022).…”