How Cilia Do the Wave

This Research in Action article was provided to LiveScience in partnership with the National Science Foundation.

Thin, hair-like biological structures called cilia are tiny but mighty. Each one, made up of more than 600 different proteins, works together with hundreds of others in a tightly-packed layer to move like a crowd at a ball game doing "the wave." Their synchronized motion helps sweep mucus from the lungs and usher eggs from the ovaries into the uterus. By controlling how fluid flows around an embryo, cilia also help ensure that organs like the heart develop on the correct side of your body.

But despite cilia's importance, scientists don't have a good understanding of the mechanism that controls how cilia beat in unison to perform their many essential functions. To investigate this, a group of federally-funded researchers at Brandeis University, led by Zvonimir Dogic and Daniela Nicastro, created the first-ever models of artificial cilia.

The main ingredient was microtubules, or hollow protein tubes that give plant and animal cells structure and help organize and move their components for cell division. Motor proteins and a compound that assembles microtubules into bundles also went into the mix.

Inside a machine called a flow chamber, the artificial cilia moved like the real thing: They beat together in a series of synchronized, self-organized waves. In some cases, as you see here, the lab-made cilia could even push debris along the surface of a bubble, mimicking transport along a cell's surface.

As the first example of a system that beats like cilia, the new models could have applications in fields ranging from cell biology to physics and nanoscience. The models will also open new doors for studying ciliopathies, rare but serious genetic disorders that result when cilia don't move normally.

The researchers anticipate that artificial cilia could even shed light on other self-organizing systems, such as bacterial colonies, flocks of migrating birds and traffic patterns.

This research was supported by the National Institutes of Health (NIH) and the National Science Foundation (NSF). To see more cool images and videos of basic biomedical research in action, visit the NIH's Biomedical Beat Cool Image Gallery.

Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the National Science Foundation. See the Research in Action archive.

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