ScienceDaily, 5 January 2021. https://www.sciencedaily.com/releases/2021/01/210105104832.htm
First direct observation of magnetic field affecting autofluorescence of flavins in living cells.
Summary: New research shows how X-Men villain Magneto’s super powers could really work. Researchers have made the first observations of biological magnetoreception – live, unaltered cells responding to a magnetic field in real time. This discovery is a crucial step in understanding how animals from birds to butterflies navigate using Earth’s magnetic field and addressing the question of whether weak electromagnetic fields in our environment might affect human health.
Researchers in Japan have made the first observations of biological magnetoreception — live, unaltered cells responding to a magnetic field in real time. This discovery is a crucial step in understanding how animals from birds to butterflies navigate using Earth’s magnetic field and addressing the question of whether weak electromagnetic fields in our environment might affect human health.
“The joyous thing about this research is to see that the relationship between the spins of two individual electrons can have a major effect on biology,” said Professor Jonathan Woodward from the University of Tokyo, who conducted the research with doctoral student Noboru Ikeya. The results were recently published in the Proceedings of the National Academy of Sciences of the United States of America (PNAS).
Researchers have suspected since the 1970s that because magnets can attract and repel electrons, Earth’s magnetic field, also called the geomagnetic field, could influence animal behavior by affecting chemical reactions. When some molecules are excited by light, an electron can jump from one molecule to another and create two molecules with single electrons, known as a radical pair. The single electrons can exist in one of two different spin states. If the two radicals have the same electron spin, their subsequent chemical reactions are slow, while radical pairs with opposite electron spins can react faster. Magnetic fields can influence electron spin states and thus directly influence chemical reactions involving radical pairs. Read more at: https://www.sciencedaily.com/releases/2021/01/210105104832.htm
Article Reference: University of Tokyo. “Magnets dim natural glow of human cells, may shed light on how animals migrate: First direct observation of magnetic field affecting autofluorescence of flavins in living cells.” ScienceDaily. <www.sciencedaily.com/releases/2021/01/210105104832.htm>
- Noboru Ikeya, Jonathan R. Woodward. Cellular autofluorescence is magnetic field sensitive. Proceedings of the National Academy of Sciences, 2021; 118 (3): e2018043118 DOI: 10.1073/pnas.2018043118
The radical pair mechanism is the favored hypothesis for explaining biological effects of weak magnetic fields, such as animal magnetoreception and possible adverse health effects. To date, however, there is no direct experimental evidence for magnetic effects on radical pair reactions in cells, the fundamental building blocks of living systems. In this paper, using a custom-built microscope, we demonstrate that flavin-based autofluorescence in native, untreated HeLa cells is magnetic field sensitive, due to the formation and electron spin–selective recombination of spin-correlated radical pairs. This work thus provides a direct link between magnetic field effects on chemical reactions measured in solution and chemical reactions taking place in living cells.
We demonstrate, by direct, single-cell imaging kinetic measurements, that endogenous autofluorescence in HeLa cells is sensitive to the application of external magnetic fields of 25 mT and less. We provide spectroscopic and mechanistic evidence that our findings can be explained in terms of magnetic field effects on photoinduced electron transfer reactions to flavins, through the radical pair mechanism. The observed magnetic field dependence is consistent with a triplet-born radical pair and a B1/2 value of 18.0 mT with a saturation value of 3.7%.