Using clones and copper to resolve the genetic architecture of metal tolerance in a marine invader
Using clones and copper to resolve the genetic architecture of metal tolerance in a marine invader
复制标题
使用克隆和铜来解决海洋入侵者金属耐受性的遗传结构
作者：
Louise A. McKenzie;E. Johnston;R. Brooks
入侵物种的全球传播可能会因适应人类管理这些物种的做法而得到促进。例如，适应船体上金属基防污杀菌剂的海洋无脊椎动物可能更有可能被引入并在金属污染的环境中定居。我们通过研究一种广泛存在的入侵性海洋苔藓虫——水孢子虫（Watersipora subtorquata）对铜的耐受性和恢复能力的克隆变异来验证这一观点。我们克隆了该生物的菌落，通过环境设计对一个基因型的多个环境进行独立测试，并建立了遗传方差-协方差矩阵。基因型暴露于铜浓度梯度中，并在暴露期间和恢复期后测量生长情况。暴露期和恢复期的生长均存在显著的基因型与环境交互作用。我们发现克隆的耐受性和从铜暴露中恢复的能力发生了变化，暴露期间的生长明显抵消了暴露后的生长。暴露期间和暴露后生长之间的遗传相关性较弱，进一步表明它们是不同的性状。总体而言，该种群内的遗传变异表明，有相当大的适应铜的潜力，但这是以在未污染的环境中生长为代价的。
The global spread of invasive species may be facilitated by adaptation to the practices that humans use to manage those species. For example, marine invertebrates that adapt to metal-based antifouling biocides on ship hulls may be more likely to be introduced to and establish in metal-polluted environments. We tested this idea by studying clonal variation in tolerance to, and ability to recover from, exposure to copper in a widespread invasive marine bryozoan, Watersipora subtorquata. We cloned colonies of this organism to independently test multiple environments in a genotype by environment design, and then created a genetic variance–covariance matrix. Genotypes were exposed to a gradient of copper concentrations and growth measured during exposure and after a recovery period. There was a significant genotype × environment interaction in growth during exposure and recovery. We found clonal variation in tolerance and ability to recover from exposure to copper, with growth during exposure apparently trading off against growth after exposure. A weak genetic correlation between growth during and after exposure further indicated that they are separate traits. Overall, the genetic variation within this population indicates that there is considerable potential for adaptation to copper, but this comes at a cost to growth in unpolluted environments.