Zepernick Brittany N, Niknejad David J, Stark Gwendolyn F, Truchon Alexander R, Martin Robbie M, Rossignol Karen L, Paerl Hans W, Wilhelm Steven W
Department of Microbiology, University of Tennessee, Knoxville, TN, United States.
Institute of Marine Sciences, University of North Carolina at Chapel Hill, Morehead City, NC, United States.
Front Microbiol. 2022 Nov 25;13:1044464. doi: 10.3389/fmicb.2022.1044464. eCollection 2022.
Harmful algal blooms (HABs) caused by the toxin-producing cyanobacteria spp., can increase water column pH. While the effect(s) of these basified conditions on the bloom formers are a high research priority, how these pH shifts affect other biota remains understudied. Recently, it was shown these high pH levels decrease growth and Si deposition rates in the freshwater diatom and natural Lake Erie (Canada-US) diatom populations. However, the physiological mechanisms and transcriptional responses of diatoms associated with these observations remain to be documented. Here, we examined with a set of morphological, physiological, and transcriptomic tools to identify cellular responses to high pH. We suggest 2 potential mechanisms that may contribute to morphological and physiological pH effects observed in . Moreover, we identified a significant upregulation of mobile genetic elements in the genome which appear to be an extreme transcriptional response to this abiotic stress to enhance cellular evolution rates-a process we have termed "" We discuss the ecological and biogeochemical effects high pH conditions impose on fresh waters and suggest a means by which freshwater diatoms such as may evade high pH stress to survive in a "basified" future.
由产毒素的蓝藻物种引起的有害藻华（HABs）会使水柱pH值升高。虽然这些碱性条件对藻华形成者的影响是一个高度优先的研究课题，但这些pH值变化如何影响其他生物群落仍未得到充分研究。最近的研究表明，这些高pH值会降低淡水硅藻以及加拿大 - 美国伊利湖自然硅藻种群的生长和硅沉积速率。然而，与这些观察结果相关的硅藻的生理机制和转录反应仍有待记录。在这里，我们使用一组形态学、生理学和转录组学工具进行研究，以确定细胞对高pH值的反应。我们提出了两种可能导致在......中观察到的形态和生理pH效应的潜在机制。此外，我们在......基因组中发现了移动遗传元件的显著上调，这似乎是对这种非生物胁迫的一种极端转录反应，以提高细胞进化速率——我们将这个过程称为“......”。我们讨论了高pH条件对淡水施加的生态和生物地球化学影响，并提出了一种像......这样的淡水硅藻可能逃避高pH胁迫以在“碱化”未来中生存的方法。
