Physiological and Proteomics Analyses Reveal Low-Phosphorus Stress Affected the Regulation of Photosynthesis in Soybean

Abstract

Previous studies have revealed a significant genetic relationship between phosphorus (P)-efficiency and photosynthesis-related traits in soybean. In this study, we used proteome profiling in combination with expression analysis, biochemical investigations, and leaf ultrastructural analysis to identify the underlying physiological and molecular responses. The expression analysis and ultrastructural analysis showed that the photosynthesis key genes were decreased at transcript levels and the leaf mesophyll and chloroplast were severely damaged after low-P stress. Approximately 55 protein spots showed changes under low-P condition by mass spectrometry, of which 17 were involved in various photosynthetic processes. Further analysis revealed the depression of photosynthesis caused by low-P stress mainly involves the regulation of leaf structure, adenosine triphosphate (ATP) synthesis, absorption and transportation of CO2, photosynthetic electron transport, production of assimilatory power, and levels of enzymes related to the Calvin cycle. In summary, our findings indicated that the existence of a stringent relationship between P supply and the genomic control of photosynthesis in soybean. As an important strategy to protect soybean photosynthesis, P could maintain the stability of cell structure, up-regulate the enzymes’ activities, recover the process of photosystem II (PSII), and induce the expression of low-P responsive genes and proteins.

Physiological and Biochemical Responses of Cucumis melo L. Chloroplasts to Low-Phosphate Stress

“…However, low-Pi stress improved the chlorophyll and carotenoid contents in leaves, which was different from the responses of barley and soybean to low-Pi stress ( Frydenvang et al, 2015 ; Chu et al, 2018 ). We found that the leaf water content and free water content in low-Pi were significantly low relative to the control (the data wasn’t represented).…”

“…These absorb, transport, and convert light energy into ATP and NADPH which, in turn, drive CO 2 assimilation in the stroma ( Rochaix, 2011 ). Earlier studies on soybean, maize, and other crops showed that Pi starvation inhibited photosynthesis ( Fredeen et al, 1990 ; Usuda and Shimogawara, 1992 ; Chu et al, 2018 ). It was believed that the phosphate deficiency targeted the dark reaction by decreasing ATP and NADPH, activating Rubisco, and regenerating RUBP.…”

Effect of Wastewater Irrigation on Photosynthesis, Growth, and Anatomical Features of Two Wheat Cultivars (Triticum aestivum L.)

“…In wastewater-irrigated plants, the reduced photosynthetic capacity from high levels of Na + [38] caused a reduction in WSC and glucose that was highest in the Chamran cultivar. The P-containing molecules, ATP and NADP, are essential for utilizing the energy of photosynthesis to make sugars [47], so the reduction of P in the leaves of wastewater-irrigated plants could be another reason for the reduction in carbohydrates and consequently in plant growth. Thus, the loss of carbohydrates in response to wastewater could be attributed to nutrient imbalance and impaired photosynthesis.…”

Phosphorus-Induced Adaptation Mechanisms of Rye Grown on Post-Flotation Copper Tailings

“…A low level of P in leaf mesophyll cells may have a direct effect on photosynthesis through depressed Pi availability in the chloroplast [ 80 ]. P starvation affects CO 2 assimilation by reducing the ATP-dependent regeneration of ribulose-1,5-bisphosphate and the abundance and activity of the key enzymes of the Calvin cycle, including Rubisco and Rubisco activase [ 81 , 82 ]. In addition, inhibition of photosynthesis may result from decreased activity of the photosynthetic electron transport chain (ETC) in thylakoid membranes [ 35 , 83 ].…”