Data from: 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 structures, which
are subsequently repaired or replaced through processes involving
ferritin. Additionally, some genes that function in the development and
repair of photoreceptive structures (e.g. crggm3, purp, prl, gcip, crabp1
and pax6) were also differentially expressed, raising the possibility that
a magnetic pulse might affect structures and processes unrelated to
magnetite-based magnetoreceptors.

多种动物借助地球磁场完成定向与导航，但学界对磁感受的分子机制仍缺乏深入认知。近期研究主要聚焦于两种潜在机制：(i) 基于磁铁矿（magnetite）的磁感受器；(ii) 涉及自由基对的生化反应。本研究通过RNA测序（RNA sequencing）技术，分析了虹鳟（Oncorhynchus mykiss）暴露于已知可破坏磁定向行为的磁脉冲后，其脑部的基因表达谱变化。研究共鉴定出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）也受到显著影响。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/或其他含铁结构，并通过铁蛋白介导的过程对其进行修复或替换”的假说一致。此外，部分参与光感受结构发育与修复的基因（如crggm3、purp、prl、gcip、crabp1及pax6）同样呈现差异表达，提示磁脉冲可能影响与基于磁铁矿的磁感受器无关的结构与生理过程。