When life begins, a mad whirlwind begins. This is not poetry or philosophy. This is science.
Once an egg is fertilized, billions of proteins spill over its surface, releasing a dizzying cascade of swirling patterns. These spiral arcs are a fundamental part of nascent cell division.
“The egg is a huge cell, and these proteins have to work together to find their center so that the cell knows where to divide repeatedly to form an organism,” says physicist Nikta Fakhri of the Massachusetts Institute of Technology.
“Without these wave-making proteins, there would be no cell division.”
In a new study, Fakhri and his fellow researchers examined what these vortex waves look like by studying their patterns of propagation on the cell membranes of sea star eggs (Patiria miniata).
In addition to understanding the biology of starfish oocytes, the researchers wanted to see how these patterns could compare to similar wave phenomena in other types of systems – examples of what physicists call topological defects.
As the researchers explain in the article, similar types of turbulent behavior can be observed in both physical and biological matter. On scales that range from cosmological to infinitesimal, from swirling vortices in planetary atmospheres to bioelectric signals in the heart and brain.
However, while similarities can be traced, their nature remains unexplored.
“Despite such significant progress in understanding topological defects and their functional consequences, it is not yet clear whether the statistical laws governing such topological structures in classical and quantum systems extend to a living being,” the authors explain.
Spiral ripples in starfish oocytes. (MIT)
In their experiments with starfish, the team unveiled a hormone that mimics the onset of fertilization in oocytes, in which waves signaling a protein called Rho-GTP pulsate through the membrane for several minutes at a time, and the results are displayed under a microscope, thanks to the help of fluorescent dyes. which join Rho-GTP.
By varying the concentration of the hormonal trigger, the researchers were able to observe many twisted spirals spreading across the entire surface of the egg.
“So we created a kaleidoscope of different models and looked at their dynamics,” says Fakhri.
After capturing and analyzing the phase velocity in wave structures, the researchers say, the rudiments of life observed in these sea star eggs resemble dynamics in bacterial turbulence and quantum systems of Bose-Einstein condensates.
The results are presented in the journal Physics Nature.
Sources: Photo: MIT
