Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230039, China.
High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Science Island, Hefei, Anhui 230031, China.
Zool Res. 2023 Jan 18;44(1):142-152. doi: 10.24272/j.issn.2095-8137.2022.423.
The ability to navigate long distances is essential for many animals to locate shelter, food, and breeding grounds. Magnetic sense has evolved in various migratory and homing species to orient them based on the geomagnetic field. A highly conserved iron-sulfur cluster assembly protein IscA is proposed as an animal magnetoreceptor (MagR). Iron-sulfur cluster binding is also suggested to play an essential role in MagR magnetism and is thus critical in animal magnetoreception. In the current study, we provide evidence for distinct iron binding and iron-sulfur cluster binding in MagR in pigeons, an avian species that relies on the geomagnetic field for navigation and homing. Pigeon MagR showed significantly higher total iron content from both iron- and iron-sulfur binding. Y65 in pigeon MagR was shown to directly mediate mononuclear iron binding, and its mutation abolished iron-binding capacity of the protein. Surprisingly, both iron binding and iron-sulfur binding demonstrated synergistic effects, and thus appear to be integral and indispensable to pigeon MagR magnetism. These results not only extend our current understanding of the origin and complexity of MagR magnetism, but also imply a possible molecular explanation for the huge diversity in animal magnetoreception.
远距离导航能力对于许多动物寻找庇护所、食物和繁殖地至关重要。磁感觉在各种迁徙和归巢物种中进化，使它们能够根据地磁场定位。高度保守的铁硫簇组装蛋白 IscA 被提议为动物磁受体 (MagR)。铁硫簇结合也被认为在 MagR 磁性中发挥着重要作用，因此在动物磁感受中至关重要。在本研究中，我们提供了证据表明鸽子（一种依赖地磁场导航和归巢的鸟类）的 MagR 中存在不同的铁结合和铁硫簇结合。鸽子 MagR 显示出来自铁和铁硫结合的总铁含量明显更高。鸽子 MagR 中的 Y65 被证明直接介导单核铁结合，其突变消除了该蛋白的铁结合能力。令人惊讶的是，铁结合和铁硫结合都表现出协同效应，因此似乎是鸽子 MagR 磁性的整体和不可或缺的组成部分。这些结果不仅扩展了我们对 MagR 磁性起源和复杂性的现有理解，还暗示了动物磁感受巨大多样性的可能分子解释。
