Launay Hélène, Huang Wenmin, Maberly Stephen C, Gontero Brigitte
BIP, Aix Marseille Univ CNRS, BIP UMR 7281, Marseille, France.
Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, China.
Front Plant Sci. 2020 Jul 16;11:1033. doi: 10.3389/fpls.2020.01033. eCollection 2020.
Diatoms belong to a major, diverse and species-rich eukaryotic clade, the Heterokonta, within the polyphyletic chromalveolates. They evolved as a result of secondary endosymbiosis with one or more Plantae ancestors, but their precise evolutionary history is enigmatic. Nevertheless, this has conferred them with unique structural and biochemical properties that have allowed them to flourish in a wide range of different environments and cope with highly variable conditions. We review the effect of pH, light and dark, and CO concentration on the regulation of carbon uptake and assimilation. We discuss the regulation of the Calvin-Benson-Bassham cycle, glycolysis, lipid synthesis, and carbohydrate synthesis at the level of gene transcripts (transcriptomics), proteins (proteomics) and enzyme activity. In contrast to Viridiplantae where redox regulation of metabolic enzymes is important, it appears to be less common in diatoms, based on the current evidence, but regulation at the transcriptional level seems to be widespread. The role of post-translational modifications such as phosphorylation, glutathionylation, etc., and of protein-protein interactions, has been overlooked and should be investigated further. Diatoms and other chromalveolates are understudied compared to the Viridiplantae, especially given their ecological importance, but we believe that the ever-growing number of sequenced genomes combined with proteomics, metabolomics, enzyme measurements, and the application of novel techniques will provide a better understanding of how this important group of algae maintain their productivity under changing conditions.
硅藻属于一个主要的、多样且物种丰富的真核生物分支——不等鞭毛类，它位于多源的色藻界内。它们是与一种或多种植物祖先进行次生内共生的结果，但它们确切的进化历史仍不明确。尽管如此，这赋予了它们独特的结构和生化特性，使它们能够在广泛的不同环境中繁荣生长，并应对高度多变的条件。我们综述了pH值、光照与黑暗以及二氧化碳浓度对碳吸收和同化调节的影响。我们在基因转录本（转录组学）、蛋白质（蛋白质组学）和酶活性水平上讨论了卡尔文-本森-巴斯姆循环、糖酵解、脂质合成和碳水化合物合成的调节。与代谢酶的氧化还原调节很重要的绿藻不同，基于目前的证据，这种调节在硅藻中似乎不太常见，但转录水平的调节似乎很普遍。翻译后修饰（如磷酸化、谷胱甘肽化等）以及蛋白质-蛋白质相互作用的作用一直被忽视，应该进一步研究。与绿藻相比，硅藻和其他色藻的研究较少，特别是考虑到它们的生态重要性，但我们相信，不断增加的测序基因组数量，结合蛋白质组学、代谢组学、酶测量以及新技术的应用，将有助于更好地理解这一重要藻类群体在不断变化的条件下如何维持其生产力。
