Spatiotemporal genetic structure of regional-scale Alexandrium catenella dinoflagellate blooms explained by extensive dispersal and environmental selection
Spatiotemporal genetic structure of regional-scale Alexandrium catenella dinoflagellate blooms explained by extensive dispersal and environmental selection
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DOI：
10.1016/j.hal.2019.03.013
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发表时间：
2019-06-01
期刊：
影响因子：
6.6
通讯作者：
Erdner, Deana L.
中科院分区：
文献类型：
--
作者：
Gao, Yida;Sassenhagen, Ingrid;Erdner, Deana L.
麻痹性贝类中毒（PSP）是由甲藻链状亚历山大藻引起的一种众所周知的全球性综合征，对人类健康和渔业经济产生负面影响。因此，了解该物种的种群动态和生态学对于确定水华和相关PSP毒性的决定因素非常重要。鉴于亚历山大藻在毒性和生理学方面存在广泛的遗传异质性，对有害藻类（如亚历山大藻）的遗传种群结构的了解。链状藻也有助于理解有毒水华的发展和生态适应。本研究利用微卫星标记对多个A. catenella菌株在夏季水华期间从缅因州（GoM）海湾的几个亚区域分离，以深入了解这种经济上重要的浮游植物物种的来源和动态。至少有三个遗传上不同的A.在墨西哥湾发现了链状球菌。每一组都有来自不同次区域的代表，突出了整个区域的连通性和分散程度。这种共享的多样性可能是由于以前的沿海水华造成的孢囊床，从而保护了区域A的整体多样性。链孢种群。A.在局部水华中观察到链状藻种群，这可能是通过硅酸盐和硝酸盐/亚硝酸盐浓度等环境条件进行自然选择的结果，强调短期水团侵入和生物过程在决定海洋浮游植物种群多样性和动态方面的作用。鉴于A.尽管全球变暖和未来环境条件不断变化，但由于墨西哥湾和其他地方可能存在链状藻，有害藻华可能会在许多地区持续存在。通过不同的水文条件选择不同的遗传谱系可能会影响毒素的生产和未来的水华概况，挑战HAB控制和未来PSP风险的预测。
Paralytic Shellfish Poisoning (PSP) caused by the dinoflagellate Alexandrium catenella is a well-known global syndrome that negatively impacts human health and fishery economies. Understanding the population dynamics and ecology of this species is thus important for identifying determinants of blooms and associated PSP toxicity. Given reports of extensive genetic heterogeneity in the toxicity and physiology of Alexandrium species, knowledge of genetic population structure in harmful algal species such as A. catenella can also facilitate the understanding of toxic bloom development and ecological adaptation. In this study we employed microsatellite markers to analyze multiple A. catenella strains isolated from several sub-regions in the Gulf of Maine (GoM) during summer blooms, to gain insights into the sources and dynamics of this economically important phytoplankton species. At least three genetically distinct clusters of A. catenella were identified in the GoM. Each cluster contained representatives from different sub-regions, highlighting the extent of connectivity and dispersal throughout the region. This shared diversity could result from cyst beds created by previous coastal blooms, thereby preserving the overall diversity of the regional A. catenella population. Rapid spatiotemporal genetic differentiation of A. catenella populations was observed in local blooms, likely driven by natural selection through environmental conditions such as silicate and nitrate/nitrite concentrations, emphasizing the role of short-term water mass intrusions and biotic processes in determining the diversity and dynamics of marine phytoplankton populations. Given the wide-spread intraspecific diversity of A. catenella in GoM and potentially elsewhere, harmful algal blooms will likely persist in many regions despite global warming and changing environmental conditions in the future. Selection of different genetic lineages through variable hydrological conditions might impact toxin production and profiles of future blooms, challenging HAB control and prediction of PSP risk in the future.