Imma Perfetto
Cosmos science journalist
Biologists have discovered a new geometric mechanism in which a single cell folds and unfolds like origami.
The single celled organism, Lacrymaria olor, is known for its unique hunting strategy. It launches a neck-like proboscis, more than 30 times its original body length, to locate its prey (other microbes).
The attack takes less than 30 seconds and is completely reversible.
A new paper in the journal Science is the first to describe how such a simple cell can produce this incredible shapeshifting feat and repeat it more than 20,000 times in its lifecycle.
“This is the first example of cellular origami,” says Manu Prakash, associate professor of bioengineering at Stanford University in the US and co-author of the paper.
“We’re thinking of calling it lacrygami.”
Specifically, it is a subset of traditional origami known as “curved-crease origami”.
Prakash and Stanford graduate student Eliott Flaum used a combination of live imaging, confocal, and transmission electron microscopy to discover the 15 thin, spiralling microtubule structures which wrap inside the cell’s thin outer membrane.
They found that when the cell projects its neck it uncoils these microtubules, and the membrane unfolds. Then, as it retracts, the structures coil back up and the membrane tucks away inside the cell in well-defined pleats.
“From the minute Manu showed it to me, I have just been transfixed by this cell,” says Flaum.
“The first time I came back with a fluorescence micrograph, it was just breathtaking.”
The researchers say the work has implications in the design of synthetic systems, including micro- or nanorobotics.
“The stability and ideas from geometric control of Lacrygami we describe can be used for linear deployable structures, with applications ranging from space architecture to medical robotics,” they write.
