Epithelial cells are the "building blocks" of embryos, forming skin and lining organs and blood vessels. The University of Seville scientists argued that the novel shape of "scutoid" allows cells to stay tightly-packed, while embryos grow and their tissues curve as they form into organs.
Researchers aimed to understand which shape is most optimal to allow the cells to remain neatly packed. An assumption that cells could be bottle- or column-shaped was rejected when computer modeling suggested that epithelial cells adopt other more complex shapes.
Scutoid is prism-like, with 6 sides on one side and 5 on the other. In addition, there is a triangular face on one of the long edges of the prism.
"We propose that scutoids make possible the minimization of the tissue energy and stabilize three-dimensional packing. Hence, we conclude that scutoids are one of nature's solutions to achieve epithelial bending. Our findings pave the way to understand the three-dimensional organization of epithelial organs," the scientists revealed in the publication.
The name scutoid didn't exist in geometry before and was chosen by the researchers due to similarity to the shape of a scutellum of a beetle.
The paper titled Scutoids are a geometrical solution to three-dimensional packing of epithelia has been published Nature Communications.