  In spite of many years of research, the mechanism of avian magnetoreception
remains a mystery due to its seemingly insurmountable intricacies. Recently Xie
and colleagues proposed that IscA1 can act as a protein biocompass due to the
measured intrinsic ferromagneticity, and thus named it MagR. However, Meister's
calculations showed that the interaction energy of the magnetic moment of IscA1
with Earth's magnetic field is five magnitudes smaller than thermal fluctuation
at room temperature. The other long-proposed compass protein is cryptochrome
(Cry) with a mechanism of forming singlet-triplet radical pairs. However, this
sensory mechanism still has no inferable information transmission routes. We
propose a magnetoreception mechanism involving both the Cry and IscA1 proteins,
through which photoinduced electrons are transported to redox-regulated ion
channels to provoke neuronal responses. The structural features of the
Cry-IscA1 complex that make it suitable for long-range electron transfer are
discussed and how the magnetic effect leads to neuronal activity is described.
