Life begins with mesmerising waves

As life starts, the crazy whirl begins. That’s not poetry or philosophy. It’s in science.

Once an egg is fertilised, billions of proteins ripple out across its surface, unleashing a dizzying cascade of swirling patterns. These spiralling arcs aren’t for show, though; the phenomenon could also be pretty, but it is also a fundamental part of nascent cellular division.

“The egg is a huge cell, and these proteins need to work together to seek out its centre, so the cell knows where to divide and fold, repeatedly over, to form an organism,” says physicist Nikta Fakhri from MIT.

“Without these proteins making waves, there would be no cellular division .”

In a new study, Fakhri and fellow researchers examined what these whirling waves seem like up close, examining their propagation patterns on the cell membranes of starfish eggs (Patiria miniata).

Beyond grasping the biology of starfish oocytes, the researchers wanted to examine how these patterns might compare to similar wave phenomena in other forms of systems – samples of what physicists call topological defects.

As the researchers explain in a very new paper, these types of turbulence-like behaviours are often seen in both physical and biological matter, in scales that range between the cosmological and the infinitesimal: from swirling vortices in planetary atmospheres to bio-electrical signalling within the heart and brain.

Yet while the similarities could also be abundant, the nature of their sameness remains mysterious, theoretically speaking.


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“Despite such substantial progress within the understanding of topological defects and their functional implications, it’s not yet clear whether statistical laws that govern such topological structures in classical and quantum systems extend to living matter,” the authors explain.

In their starfish experiments, the team introduced a hormone to mimic the onset of fertilisation within the oocytes, during which triggered waves of a signalling protein called Rho-GTP ripple through the membrane for several minutes at a time, with the results being imaged via microscope thanks to the help of fluorescent dyes that attach to Rho-GTP.

By varying the concentration of the hormone trigger, the researchers were able to observe a range of swirling spirals emanating throughout the egg’s surface medium.

“In this manner, we created a kaleidoscope of various patterns and checked out their resulting dynamics,” Fakhri says.

“Not much was known about the dynamics of these surface waves in eggs, and after we started analysing and modelling these waves, we found these same patterns show up in all these other systems. It’s a manifestation of this very universal wave pattern.”

After filming and analysing the phase velocity within the wave patterns, the researchers say the very beginnings of life, as seen in these starfish eggs, resemble the dynamics observed in bacterial turbulence, active nematics, and therefore the quantum systems of Bose–Einstein condensates.

If that’s a bit jargon-heavy for you, in additional poetic and philosophical terms, it is also like – because the Killers sing – a hurricane that started turning once you were young.

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