Molecular Invertebrate Systematics and Ecology Laboratory, Rising Star Program, Transdisciplinary Research Organization for Subtropical Island Studies, University of the Ryukyus, Senbaru 1, Nishihara, Okinawa, 901-0213, Japan.
Mar Biotechnol (NY). 2010 Oct;12(5):605-17. doi: 10.1007/s10126-009-9249-3. Epub 2010 Jan 9.
Zoanthids comprise an order of benthic, generally colonial cnidarians, which can usually be distinguished from other hexacorallians by embedded sand and detritus in their mesoglea to help strengthen their structure. These animals are becoming increasingly important research subjects in biochemistry and other research fields. Their inclusion of both calcium and silica results in the need for both decalcification and desilification for internal morphological examinations. Since the methodology of hydrofluoric acid (HF) desilification has rarely been documented in zoanthids, histological surveys for zoanthid taxonomy have often been abandoned and their taxonomy is often problematic. Recent investigations utilizing molecular methods have brought a clearer understanding of zoanthid diversity, but standardization of HF treatments are still needed to provide a link between molecular and more traditional techniques, and to properly examine specimens for which molecular methods may not be an option (e.g., formalin-preserved specimens, etc.). Here, we use both "straight" HF and, for the first time with zoanthids, buffered HF (BHF) treatments at different treatment lengths (1-48 h) on polyps from three different species of zoanthids for histological examination. Section conditions were judged based on the presence/absence of embedded detritus, drag marks, and tissue condition. Results show that the BHF treatment resulted in slightly better tissue conditions for all specimens, and suggest that desilification works well regardless of treatment time for species with smaller (polyp diameter <0.5 cm), less heavily encrusted polyps. Desilification of heavily encrusted Palythoa mutuki polyps were still problematic, with at least 24 h treatment needed. To aid future research, we provide guidelines for HF treatments of zoanthid specimens.
珊瑚虫纲是一类底栖、通常为群体的刺胞动物，其中胶层中嵌入的沙子和碎屑有助于增强结构，可将其与其他六放珊瑚纲动物区分开来。这些动物在生物化学和其他研究领域正成为越来越重要的研究对象。它们的结构中同时包含钙和硅，因此需要进行脱钙和脱硅处理，以进行内部形态学检查。由于在珊瑚虫纲中很少有关于氢氟酸（HF）脱硅方法的记录，因此对于珊瑚虫纲的分类学研究通常会放弃组织学调查，其分类学也经常存在问题。最近利用分子方法进行的研究使人们对珊瑚虫纲的多样性有了更清晰的认识，但仍需要对 HF 处理方法进行标准化，以在分子技术和更传统的技术之间建立联系，并适当检查可能不适合使用分子方法的标本（例如，福尔马林保存的标本等）。在这里，我们使用“直HF”和首次用于珊瑚虫纲的缓冲 HF（BHF）处理方法，对来自三种不同珊瑚虫纲物种的息肉进行不同的处理时间（1-48 小时），以进行组织学检查。根据嵌入碎屑、拖曳痕迹和组织状况的存在/不存在来判断切片条件。结果表明，BHF 处理对所有标本的组织状况都有轻微改善，并且表明无论处理时间如何，对于较小（息肉直径<0.5 厘米）、结壳较轻的物种，脱硅效果都很好。对于结壳严重的 Palythoa mutuki 息肉的脱硅仍然存在问题，需要至少 24 小时的处理。为了帮助未来的研究，我们提供了 HF 处理珊瑚虫纲标本的指南。
