无脊椎动物金属硫蛋白(MTs)多样性及其生态服务功能

金属硫蛋白（MTs）是一类低分子量、半胱氨酸含量异常丰富的金属结合多肽，自从20世纪70年代中期发现海洋无脊椎动物MTs以来，MTs已被证明广泛存在于无脊椎动物的各个类群之中。无脊椎动物物种间的金属硫蛋白存在着显著差异，研究无脊椎动物MTs多样性并揭示其生态服务功能，在理论与实践上都至关重要。本文分析了无脊椎动物MTs的多样性：结合金属元素多样性、同形体及其变体的蛋白质遗传多样性和生态服务功能多样性，并讨论了 MTs的三个生态服务功能：MTs对重金属解毒和调节作用、MTs作为环境监测的生物标志物、MTs的环境重金属污染净化功能及其在环境污染治理中的作用。

Metallothionein diversity and its ecological service functions of invertebrates: an overview

Metallothioneins(MTs) are low molecular mass, cysteine rich metal binding polypeptides, which have been found widely distributed in invertebrates since 1975 and established a central role in the regulation of the essential metals, zinc and copper, and the detoxification of nonessential metals, cadmium and mercury. So far, more than 60 invertebrate MTs have been reported each with two and more than two MT isoforms and variants respectively in most major invertebrate groups including nematodes, annelids, echinoderm, mollusks, arthropods, pogonophora, and crustaceans. It was reported that MTs differed significantly among invertebrate species with plentiful information of biodiversity and many kinds of ecological functions, including the following three aspects: diversity of binding metals to MTs, diversity of MT isoforms and variants, and diversity of MTs ecological service functions. Up to now, however, studies on the diversity of MTs are not enough, especially on MTs ecological service functions, so that few MTs ecological functions have been found and studied in natural populations of invertebrates. For this reason, it is important to indicate the ecological service functions on the basis of the diversity of invertebrate MTs in terms of theory and practice. The diversity of invertebrate MTs are overviewed and analyzed in this paper, and their ecological service functions are also discussed in three aspects: MTs function in detoxification and regulation of heavy metals, MTs as biomarkers in environmental monitoring, purification function of MTs in environmental heavy metal pollution and their roles in the environmental pollution management.