Hardivillier Yann, Denis Françoise, Demattei Marie-Véronique, Bustamante Paco, Laulier Marc, Cosson Richard
Laboratoire de Biologie et Génétique Evolutive, Université du Maine, Avenue Olivier Messiaen 72085 Le Mans, France.
Comp Biochem Physiol C Toxicol Pharmacol. 2006 Jul;143(3):321-32. doi: 10.1016/j.cbpc.2006.03.006. Epub 2006 Mar 29.
The present study reports on the metallothionein expression in the hydrothermal vent mussel Bathymodiolus thermophilus. Metallothioneins (MT) are proteins involved in intracellular metal regulation and conserved throughout the animal kingdom. The hydrothermal vent environment presents peculiarities (high levels of sulfides and metals, low pH, anoxia) that may have driven associated species to develop original evolutionary ways to face these extreme living conditions. Mussels were exposed to different metal solutions at the atmospheric pressure. The MT mRNA levels and MT contents were measured in gills and mantles of each exposed mussel. The intracellular metal distribution was estimated in fractions obtained after the centrifugation of tissue homogenates. A few of the tested metals (Ag, Cu, Cd, Hg and Zn) were able to significantly induce MT mRNA levels. Silver was the only one that produced a significant increase of the MT protein level in both mantle and gills. The gills always presented higher MT protein levels than the mantle did, while their MT mRNA levels were similar. Our data show that MT mRNA and MT protein levels do not follow a clear relationship in the gills and mantle of B. thermophilus and we assume that a posttranscriptional control occurs in these mussels.
本研究报告了热液喷口贻贝嗜热深海贻贝中金属硫蛋白的表达情况。金属硫蛋白（MT）是参与细胞内金属调节的蛋白质，在整个动物界都很保守。热液喷口环境具有特殊性（高硫化物和金属含量、低pH值、缺氧），这可能促使相关物种发展出独特的进化方式来应对这些极端生存条件。贻贝在大气压下暴露于不同的金属溶液中。测量了每个暴露贻贝的鳃和外套膜中的MT mRNA水平和MT含量。通过组织匀浆离心后得到的组分估计细胞内金属分布。几种受试金属（银、铜、镉、汞和锌）能够显著诱导MT mRNA水平。银是唯一能使外套膜和鳃中的MT蛋白水平显著增加的金属。鳃中的MT蛋白水平总是比外套膜中的高，而它们的MT mRNA水平相似。我们的数据表明，在嗜热深海贻贝的鳃和外套膜中，MT mRNA和MT蛋白水平没有明显的相关性，我们推测这些贻贝中存在转录后调控。
