Candidate genes mediating magnetoreception in rainbow trout (Oncorhynchus mykiss)

Diverse animals use Earth's magnetic field in orientation and navigation, but little is known about the molecular mechanisms that underlie magnetoreception. Recent studies have focused on two possibilities: (i) magnetite-based receptors; and (ii) biochemical reactions involving radical pairs. We used RNA sequencing to examine gene expression in the brain of rainbow trout (Oncorhynchus mykiss) after exposure to a magnetic pulse known to disrupt magnetic orientation behaviour. We identified 181 differentially expressed genes, including increased expression of six copies of the frim gene, which encodes a subunit of the universal iron-binding and trafficking protein ferritin. Functions linked to the oxidative effects of free iron (e.g. oxidoreductase activity, transition metal ion binding, mitochondrial oxidative phosphorylation) were also affected. These results are consistent with the hypothesis that a magnetic pulse alters or damages magnetite-based receptors and/or other iron-containing...多种动物可借助地球磁场完成定向与导航，但学界对磁感受（magnetoreception）背后的分子机制仍知之甚少。近期研究主要聚焦于两类潜在机制：(i) 基于磁铁矿的磁感受器；(ii) 涉及自由基对的生化反应。本研究采用RNA测序技术，对经已知可破坏磁定向行为的磁脉冲处理后的虹鳟（Oncorhynchus mykiss）脑部的基因表达水平进行了检测。共鉴定出181个差异表达基因，其中编码通用铁结合与转运蛋白铁蛋白（ferritin）亚基的frim基因的6个拷贝的表达量显著上调。与游离铁氧化效应相关的功能通路（如氧化还原酶活性、过渡金属离子结合、线粒体氧化磷酸化）亦受到显著影响。上述结果与“磁脉冲可改变或破坏基于磁铁矿的磁感受器及/或其他含铁”的假说相符。