DIA-based quantitative proteomics reveals the protein regulatory networks of floral thermogenesis in Nelumbo nucifera

ABSTRACT: The flower chambers of sacred lotus (Nelumbo nucifera) can maintain a relatively stable temperature during anthesis despite the large environmental temperature fluctuations. However, the regulatory mechanism of floral thermogenesis remains largely unclear. To further understand the molecular basis of floral thermogenesis in N. nucifera, we obtained a comprehensive protein expression profile from receptacles at five developmental stages using data-independent acquisition (DIA)-based quantitative proteomics technology in the present study. A total of 6913 proteins were identified and quantified, of which 3513 significantly differentially expressed proteins (DEPs) were screened. The expression patterns of the DEPs were classified by time series analysis, and two clusters related to the thermogenesis pattern of receptacles were obtained. Among them, 640 proteins were highly expressed during thermogenesis whose functional annotation showed that they were mainly involved in the tricarboxylic acid cycle, starch and sucrose metabolism, redox processes, and aerobic respiration, etc. Citrate synthase was identified as the top hub protein (highly connected protein) in the protein-protein interaction (PPI) network analysis. Next, the content of alternative oxidase (AOX) and plant uncoupling protein (pUCP) in different tissues was determined and indicated that AOX was specifically expressed in the thermogenic receptacles, while pUCP showed significantly low expression in the receptacles compared to non-thermogenic leaves. Subsequently, a protein module highly related to the thermogenic phenotype was identified by the weighted gene co-expression network analysis (WGCNA), which was mainly involved in metabolic processes, fatty acid degradation and ubiquinone synthesis. In addition, the change of H2O2 content detected from the receptacles at the five stages was highly correlated with the expression trend of AOX. In summary, the mechanism of floral thermogenesis in N. nucifera involves complex regulatory networks including tricarboxylic acid cycle metabolism, starch and sucrose metabolism, active oxygen species signaling, fatty acid degradation, and ubiquinone synthesis, etc.

ORGANISM(S): Nelumbo Nucifera

SUBMITTER: Yi Ding  

PROVIDER: PXD024269 | iProX | Sat Feb 20 00:00:00 GMT 2021

REPOSITORIES: iProX