UCIBIO-Applied Molecular Biosciences Unit, Department of Life Sciences, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal.
Associate Laboratory i4HB, Institute for Health and Bioeconomy, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal.
Mar Drugs. 2022 Mar 25;20(4):224. doi: 10.3390/md20040224.
The vast ocean holds many unexplored organisms with unique adaptive features that enable them to thrive in their environment. The secretion of fluorescent proteins is one of them, with reports on the presence of such compounds in marine annelids being scarce. The intertidal sp. is an example. The worm secretes copious amounts of mucus, that when purified and concentrated extracts, yield strong fluorescence under UV light. Emission has two main maxima, at 400 nm and at 500 nm, with the latter responsible for the blue-greenish fluorescence. Combining proteomics and transcriptomics techniques, we identified ubiquitin, peroxiredoxin, and 14-3-3 protein as key elements in the mucus. Fluorescence was found to be mainly modulated by redox status and pH, being consistently upheld in extracts prepared in Tris-HCl buffer with reducing agent at pH 7 and excited at 330 nm. One of the proteins associated with the fluorescent signal was localized in secretory cells in the pharynx. The results indicate that the secretion of fluorescent proteinaceous complexes can be an important defense against UV for this dweller. Additionally, the internalization of fluorescent complexes by ovarian cancer cells and modulation of fluorescence of redox status bears important considerations for biotechnological application of mucus components as markers.
广阔的海洋蕴藏着许多具有独特适应特征的未被探索的生物体，使它们能够在其环境中茁壮成长。荧光蛋白的分泌就是其中之一，关于海洋环节动物中存在这种化合物的报道很少。潮间带 sp. 就是一个例子。这种蠕虫分泌大量黏液，经过纯化和浓缩提取后，在紫外光下会产生强烈的荧光。发射有两个主要的最大值，分别在 400nm 和 500nm，后者负责产生蓝绿色荧光。通过蛋白质组学和转录组学技术，我们鉴定出泛素、过氧化物酶和 14-3-3 蛋白是黏液中的关键成分。荧光主要受氧化还原状态和 pH 值的调节，在 pH 值为 7 的 Tris-HCl 缓冲液中加入还原剂制备的提取物中保持一致，并在 330nm 处激发。与荧光信号相关的一种蛋白质定位于咽部的分泌细胞中。研究结果表明，荧光蛋白复合物的分泌可能是这种生物抵御紫外线的重要防御机制。此外，荧光复合物被卵巢癌细胞内化以及氧化还原状态的荧光调节，为将黏液成分作为标记物应用于生物技术提供了重要的考虑因素。
