A magnetic protein biocompass

Abstract

The notion that animals can detect the Earth's magnetic field was once ridiculed, but is now well established. Yet the biological nature of such magnetosensing phenomenon remains unknown. Here, we report a putative magnetic receptor (Drosophila CG8198, here named MagR) and a multimeric magnetosensing rod-like protein complex, identified by theoretical postulation and genome-wide screening, and validated with cellular, biochemical, structural and biophysical methods. The magnetosensing complex consists of the identified putative magnetoreceptor and known magnetoreception-related photoreceptor cryptochromes (Cry), has the attributes of both Cry- and iron-based systems, and exhibits spontaneous alignment in magnetic fields, including that of the Earth. Such a protein complex may form the basis of magnetoreception in animals, and may lead to applications across multiple fields.

Uptake of magnetic nanoparticles for adipose-derived stem cells with multiple passage numbers

“…Here, we measured the magnetosensing protein by q-PCR, which was recently reported to be capable of responding to magnetic interaction (Fig. 5c) [29]. We found that with the increase of passage numbers, the expression of magnetosensing protein was down-regulated and the expression of magnetosensing protein was maximized when the cells were cultured on assemblies of nanoparticles.…”

Identification of medaka magnetoreceptor and cryptochromes

“…It has also been verified that human CRY2 has the molecular capability to function as a light-sensitive magnetosensor (Foley et al, 2011). Besides, Xie's group has reported the co-purification of MAGR and CRY2 in human (Qin et al, 2016). Therefore, using medaka as a vertebrate model for magnet biology will not only boost our knowledge of animal MR but also cast light on understanding human MR. On the other hand, magnetogenetics that combine the genetic targeting of MagR with remote magnetic stimulation has been developed as a promising method for non-invasive neuron stimulation, which might replace the invasive approaches such as optogenetics and deep-brain stimulation in neurobiology research (Long et al, 2015).…”

“…Therefore, these results indicate that medaka cry1aa, cry1ab, cry1ba might be mammalian-like cry genes, and cry2 might be Drosophila-like genes, whereas cry5 belongs to photolyase genes. Furthermore, it has been reported that human CRY2, pigeon Cry4, garden warbler Cry3 and cockroaches Cry2 are involved in MR (Liedvogel and Mouritsen, 2010;Foley et al, 2011;Bazalova et al, 2016;Qin et al, 2016). Specifically, pigeon Cry4 and human CRY2 have shown the ability to form complexes with MagR and can be co-purified (Qin et al, 2016).…”

“…Furthermore, it has been reported that human CRY2, pigeon Cry4, garden warbler Cry3 and cockroaches Cry2 are involved in MR (Liedvogel and Mouritsen, 2010;Foley et al, 2011;Bazalova et al, 2016;Qin et al, 2016). Specifically, pigeon Cry4 and human CRY2 have shown the ability to form complexes with MagR and can be co-purified (Qin et al, 2016). Hence, medaka cry2 might be a potential target for future medaka magnet biology study.…”

“…Recently, Xie and his colleagues have identified a crucial partner protein Drosophila CG8198, the homologue of bacterial iron-sulfur cluster assembly Isca1, complementary to Cry that enables polarity sensing of magnetic fields. They named it as magnetoreceptor (MagR) and proposed the Cry/MagR system, in which the protein complex of Cry and MagR mediates MR (Qin et al, 2016).…”