Understanding of the postgerminative development response to salinity and drought stresses in cucumber seeds by integrated proteomics and transcriptomics analysis.

The postgerminative development is a complex, genetically programmed process, and also the most dangerous period before the developing seedlings reach the autotrophy state. To obtain a comprehensive understanding of postgerminative development mechanism, the study focuses on an integrative analysis on transcriptome, proteome, and microRNA in cucumber seeds under drought and salt stress. Drought and salt stress caused differential expression of 4197 mRNAs, 36 microRNAs and 768 proteins compared with the control, and 827 mRNAs, 364 proteins, and 12 microRNAs were shared by the two stresses. Numerous common differentially expressed genes and proteins participated the signal transduction of plant hormone, photosynthesis, and argine and proline metabolism. We noted the correlation among nitric oxide, polyamine, proline, and ethylene metabolism, thereby helping to elucidate the role of these substances, which are derived either directly or indirectly from arginine, in the regulation of abiotic stress and provide a basis for building better network-based molecular models in further research. Above findings contribute to new and useful information regarding the common molecular mechanisms during cucumber seedling development under drought and salt stress. SIGNIFICANCE: Water scarcity and high salt are two of the most destructive and wide stress factors which limit the growth and progression of plants by affecting a variety of vital physiological and biochemical processes. Our study focuses on an integrative analysis on transcriptome, proteome, and microRNA for confirming the essential regulators as well as pathways using cucumber postgerminative development under drought and salt stress. Arginine metabolism is a vital response to abiotic stress during cucumber seed germination.