Geometry’s newest shape is in our cells

NEWDELHI: Scientists have discovered a new shape called scutoid while studying nature’s way of moulding tissue to form the skin, cavity linings and the building blocks of organs.

The shape, which has five sides on one end and six on the other and a triangular surface on one of its longer edges. Scientists have referred to it as a twisted prism kind of shape that allows the tissue to mould around organs.

Epithelial tissue, one of the four kinds of tissue that forms the human body, is composed of epithelial cells packed together in a particular formation that has been given a nifty name: scutoid.

“During the modelling process, the results we saw were weird,” Javier Buceta, a lead author of the study, said in an e-mail to HT .

“Our model predicted that as the curvature of the tissue increases, columns and bottle-shapes were not the only shapes that cells may develop. To our surprise, the additional shape didn’t even have a name in math! One does not normally have the opportunity to name a new shape.”

The name is a reference to its similarity to the scutellum, the lowest most segment of an insect’s thorax, the midsection. The resemblance is striking if one looks at the posterior of a Protaetia speciosa beetle of the Cetoniinae sub-family.

Epithelial cells are the key cells during embryonic development and are the building blocks of tissues and organs. Epithelial tissue doesn’t just form complex 3D shapes and the outer skin layer but also the inner lining of blood vessels.

Till now, the widely accepted belief is the epithelial cells assume columnar or bottle-like shapes.

“Studies about epithelial cells have focused mostly on one side, the surface of these cells , partly because of technical limitations, and extrapolated that surface as a proxy for their three-dimensional structure,” Buceta explained. “We made a computational model that predicted these shapes and then confirmed this result in a number of tissues of different animals.”

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