珊瑚骨骼形成的生物机制研究进展

BIOLOGICAL MECHANISM OF CORAL SKELETON FORMATION:PROGRESS AND PROSPECTS

珊瑚碳酸钙骨骼作为珊瑚礁或珊瑚林的结构基础,在维持海洋生物多样性和全球碳循环中发挥着重要作用。珊瑚生物矿化是一个复杂的过程,受到体内有机基质、晶体自身生长调控,以及外界环境等多方面的综合调控作用,迄今对珊瑚骨骼钙化过程中生物调控的认识仍相当有限。文章从不同珊瑚类群的骨骼结构特征及演化历史、有机基质的调控机制、珊瑚钙化模型和环境因素对珊瑚钙化的影响等方面,综述了八放珊瑚与六放珊瑚的造礁石珊瑚钙化过程的研究进展,重点阐述了组织-骨骼界面的钙化细胞结构和离子运输途径,并梳理出了初步的珊瑚钙化模型。从不同碳酸钙晶型的骨骼结构、有机基质蛋白组成上的低共有率和生物控制下的钙化过程差异性表明八放珊瑚与造礁石珊瑚可能采用了不同的珊瑚钙化策略。未来珊瑚生物矿化研究需融合多学科技术进一步探究骨骼形成机制,结合海洋环境变化记录,揭示驱动珊瑚骨骼形成的环境因素,为理解珊瑚如何应对当今全球变暖和海洋酸化事件提供理论基础。

Corals precipitate calcium carbonate(CaCO3)skeletons to form reef-based ecosystems,playing an important role in maintaining marine biodiversity and global carbon cycle.Coral biomineralization is a complex dynamic process,which is regulated comprehensively by skeletal organic matrix,biological control of crystal growth,and ocean geochemistry.To date,our knowledge of the biological regulation of coral skeleton formation is still quite limited.We summarized the research progress in the calcification process of Octocorallia and Scleractinia from the perspectives of skeleton structure and evolutionary history,the regulation mechanism of skeletal organic matrix,coral calcification model,and the influence of environmental factors on coral calcification.We focused on the structure of calicoblastic cells and ion transport pathway at the tissue-skeleton interface,and outlined a preliminary coral calcification model.The skeleton structure of different CaCO3 polymorphs,the low common rate of organic matrix proteins,and the difference in biologically controlled calcification process indicated that Octocorallia and Scleractinia might employ different coral calcification strategies.Future studies on coral biomineralization shall integrate the advantages of multiple disciplines to explore the mechanism of coral skeletal formation and to reveal the environmental factors that drive skeletal formation.It is necessary to provide a preliminary framework for understanding how corals respond to modern global warming and ocean acidification trends.