CHROMEVOL-XENOMAR Group, Departamento de Biología Celular y Molecular, Universidade da Coruña, E15071 A Coruña, Spain.
Comp Biochem Physiol C Toxicol Pharmacol. 2012 Mar;155(2):175-81. doi: 10.1016/j.cbpc.2011.09.003. Epub 2011 Sep 16.
Marine biotoxins synthesized by Harmful Algal Blooms (HABs) represent one of the most important sources of contamination in marine environments as well as a serious threat to fisheries and aquaculture-based industries in coastal areas. Among these biotoxins Okadaic Acid (OA) is of critical interest as it represents the most predominant Diarrhetic Shellfish Poisoning biotoxin in the European coasts. Furthermore, OA is a potent tumor promoter with aneugenic and clastogenic effects on the hereditary material, most notably DNA breaks and alterations in DNA repair mechanisms. Therefore, a great effort has been devoted to the biomonitoring of OA in the marine environment during the last two decades, mainly based on physicochemical and physiological parameters using mussels as sentinel organisms. However, the molecular genotoxic effects of this biotoxin make chromatin structure a good candidate for an alternative strategy for toxicity assessment with faster and more sensitive evaluation. To date, the development of chromatin-based studies to this purpose has been hampered by the complete lack of information on chromatin of invertebrate marine organisms, especially in bivalve molluscs. Our preliminary results have revealed the presence of histone variants involved in DNA repair and chromatin specialization in mussels and clams. In this work we use this information to put forward a proposal focused on the development of chromatin-based tests for OA genotoxicity in the marine environment. The implementation of such tests in natural populations has the potential to provide an important leap in the biomonitoring of this biotoxin. The outcome of such monitoring may have critical implications for the evaluation of DNA damage in these marine organisms. They will provide as well important tools for the optimization of their harvesting and for the elaboration of additional tests designed to evaluate the safety of their consumption and potential implications for consumer's health.
海洋生物毒素由有害藻类（HABs）合成，是海洋环境中最重要的污染来源之一，也是沿海地区渔业和水产养殖业的严重威胁。在这些生物毒素中，冈田酸（OA）是一种重要的毒素，因为它是欧洲沿海地区最主要的腹泻性贝类毒素。此外，OA 是一种有效的肿瘤促进剂，对遗传物质具有诱变和断裂作用，尤其是 DNA 断裂和 DNA 修复机制的改变。因此，在过去的二十年中，人们致力于海洋环境中 OA 的生物监测，主要基于使用贻贝作为指示生物的物理化学和生理参数。然而，这种生物毒素的分子遗传毒性使染色质结构成为毒性评估的替代策略的良好候选物，具有更快和更敏感的评估。迄今为止，由于缺乏有关无脊椎海洋生物，特别是双壳类软体动物的染色质的完整信息，基于染色质的研究的发展受到了阻碍。我们的初步结果表明，贻贝和蛤中存在参与 DNA 修复和染色质特化的组蛋白变体。在这项工作中，我们利用这些信息提出了一个基于染色质的 OA 遗传毒性测试的开发提案，用于海洋环境。在自然种群中实施这些测试有可能为这种生物毒素的生物监测提供重要的飞跃。这种监测的结果可能对这些海洋生物的 DNA 损伤评估具有关键意义。它们还将为优化其收获提供重要工具，并为设计用于评估其食用安全性和对消费者健康的潜在影响的额外测试提供重要工具。
