Abstract

Background

The ability to use dissolved organic phosphorus (DOP) is important for survival and competition when phytoplankton are faced with scarcity of dissolved inorganic phosphorus (DIP). However, phosphorus availability to the freshwater dinoflagellate Peridinium bipes has received relatively little attention, the efficiency of glycerol phosphate use by phytoplankton has rarely been investigated, and the regulatory molecular mechanisms remain unclear.

Result

In the present study, cultures of the freshwater dinoflagellate Peridinium bipes were set up in 119 medium (+DIP), DIP-depleted 119 medium (P-free), and β-glycerol phosphate-replacing-DIP medium (+DOP). Gene expression was analyzed using transcriptomic sequencing. The growth rate of cells in DOP treatment group was similar to that in DIP group, but chlorophyll a fluorescence parameters RC/CS₀, ABS/CS₀, TR₀/CS₀, ET₀/CS₀ and RE₀/CS₀ markedly decreased in the DOP group. Transcriptomic analysis revealed that genes involved in photosynthesis, including psbA, psbB, psbC, psbD, psaA and psaB, were downregulated in the DOP group relative to the DIP group. Glycerol-3-phosphate dehydrogenase and glyceraldehyde-3-phosphate dehydrogenase, rather than alkaline phosphatase, were responsible for β-glycerol phosphate use. Intercellular gluconeogenesis metabolism was markedly changed in the DOP group. In addition, genes involved in ATP synthases, the TCA cycle, oxidative phosphorylation, fatty acid metabolism and amino acid metabolism in P. bipes were significantly upregulated in the DOP group compared with the DIP treatment.

Conclusions

These findings suggested that β-glycerol phosphate could influence the photosynthesis and metabolism of P. bipes, which provided a comprehensive understanding of the phosphorus physiology of P. bipes. The mechanisms underlying the use of β-glycerol phosphate and other DOPs are different in different species of dinoflagellates and other phytoplankton. DIP reduction may be more effective in controlling the bloom of P. bipes than DOP reduction.

中文翻译：

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通过生理和转录组学分析揭示甘油磷酸酯（DOP）对鞭毛鞭毛二倍体的影响

摘要

背景

当浮游植物面临稀有无机磷（DIP）匮乏时，使用溶解有机磷（DOP）的能力对于生存和竞争至关重要。然而，淡水鞭毛鞭毛双足动物的磷利用率受到的关注相对较少，浮游植物对磷酸甘油酯的利用效率尚未得到研究，并且调节分子机制仍不清楚。

结果

在本研究中，在119培养基（+ DIP），DIP耗尽的119培养基（无P）和β-磷酸甘油替代-DIP培养基（+ DOP）中建立了淡水鞭毛鞭毛双足动物的培养物。使用转录组测序分析基因表达。在DOP治疗组的细胞的生长速度为在DIP组相似，但叶绿素一个荧光参数RC / CS ₀，ABS / CS ₀，TR ₀ / CS ₀，ET ₀ / CS ₀和RE ₀ / CS ₀显着地在DOP组中有所下降。转录组学分析表明，参与光合作用的基因包括psbA，相对于DIP组，DOP组中的psbB，psbC，psbD，psaA和psaB下调。β-甘油磷酸的使用是甘油3-磷酸脱氢酶和甘油醛-3-磷酸脱氢酶而不是碱性磷酸酶。DOP组细胞间糖异生代谢明显改变。此外，与DIP处理相比，DOP组的P. bipes中参与ATP合酶，TCA循环，氧化磷酸化，脂肪酸代谢和氨基酸代谢的基因显着上调。

结论

这些发现表明，β-甘油磷酸酯可能影响P. Bipes的光合作用和代谢，从而提供了对P. Bipes磷生理的全面了解。使用β-甘油磷酸酯和其他DOP的潜在机制在不同种类的鞭毛藻和其他浮游植物中有所不同。减少DIP可能比减少DOP更加有效地控制了双峰假单胞菌的开花。