How do birds and insects navigate in the wide world? For years, scientists have believed they do so by orienting themselves to the earth’s magnetic fields, but haven’t been able to figure out how. Until, possibly, now.
When a protein is polymerized and coupled with another well-known protein, it aligns with a magnetic field, according to scientists with Peking University, the Chinese Academy of Sciences and Tsinghua University has identified.
It’s given that homing pigeons use magnetic fields to guide themselves, but investigators haven’t determined what the mechanism is that allows them to do so. The Chinese researchers believe they may have found the chemistry, even if they haven’t connected it to magnetic sensing — a magnetic protein complex.
Researchers examined the genome of a fruit fly that can sense magnetic fields and found a gene that creates a protein that responds to iron. They renamed it MagR.
They then polymerized that protein and coupled it with cryptochrome, a light-sensing protein that’s in the eyes of some animals. Using a microscope, the scientists brought iron objects near and watched what happened: the protein complex lined up like a needle in a compass. By itself, cryptochome isn’t sensitive to magnetism.
The researchers realize their findings don’t mean the protein complex is definitively responsible for magnetic sensing, but maybe it is. What if the protein complex lined up inside the eye of a pigeon? It could perhaps cause a reaction with other proteins or even cells, and these could impact nerve cells.
The Chinese scientists say that the protein complex is in many organisms with magnetic sensing, such as pigeon eyes. They want others to find out if removing the protein complex from animals or insects with magnetic sensing would cause them to lose this ability. If it did, then this magnetic protein complex could be considered as responsible for the magnetic sensing ability.
This story based on an article in Nature Materials. Source >>
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