The discovery has important implications for human health because lack of cilia can lead to serious diseases such as polycystic kidney disease, blindness and neurological disorders.
Using mouse models, Penn State cellular biologist Aimin Liu and his colleagues discovered a protein that is required for the growth of critical, hair-like structures called cilia on cell surfaces. The cilia on a mouse embryo, shown in this micrograph, would not be able to grow without the protein C2cd3. Credit: Aimin Liu Lab, Penn State University.
"If we want to better understand and treat diseases related to cilium development, we need to identify important regulators of cilium growth and learn how those regulators function," said co-author Aimin Liu, associate professor of biology at Penn State. "This work gives us significant insight into one of the earliest steps in cilium formation."
The researchers describe their findings in a paper that will be published online in the Proceedings of the National Academy of Sciences during the week of 27 January 2014. In addition to Liu, authors include Penn State cellular biologists Xuan Ye, Huiqing Zeng and Gang Ning, as well as Jeremy F. Reiter, a biophysicist at the University of California - San Francisco.
Cilia, which are present on the surface of almost all mammalian cells, are responsible for sending, receiving, and processing information within the body. "You could think of cilia as the cells' antennae," Liu said. "Without cilia, the cells can't sense what's going on around them, and they can't communicate." Cilia also perform important filtering and cleansing functions. For example, cilia inside the trachea, or windpipe, trap and prevent bacteria from entering the lungs.
In a previous study, Liu and his colleagues learned that a protein called C2cd3 is important for cilium formation because mice that lacked this protein exhibited severe developmental problems typically associated with the lack of cilia. "At the time we knew only that if we get rid of the protein, the cells in the animal would not grow cilia," Liu said. "We didn't understand why, but now we do."
A cilium grows from a centriole, a structure that clings to the inner surface of the cell and serves as an anchor for the cilium. Before a cell can grow a cilium, it needs to assemble a set of appendages at one end of the centriole. These appendages can then connect the centriole to the cell surface, allowing the outgrowth of a cilium. Just how these appendages are assembled, though, remained a mystery for more than four decades since their discovery in 1962.
Liu and his colleagues found that appendages were not assembled at the end of the centriole when the C2cd3 protein is not present. As a result, the centriole is not associated with the cell membrane and cannot recruit other proteins for the further growth of the cilium. "So our protein is required for the very first step of putting a cilium together," Liu explained. "Without those appendages, the cilium growth cannot happen."
The researchers hope their discovery will lead to greater knowledge of the process of cilium development and, eventually, to treatments for a wide range of health problems that fall under the label of ciliopathy. "Ciliopathy is a scientific term that covers a lot of diseases," Liu said. As well as contributing to cystic disorders in the kidney and liver, lack of cilia can lead to blindness or deafness, since cilia in the retina serve as receptors that process light stimulation and cilia within the ear are required in neurons that translate sound waves into neural signals.
The research was funded by the National Institutes of Health (R01AR054396, R01GM095941), the Burroughs Wellcome Fund, the Packard Foundation, the Program for Breakthrough Biomedical Research, an American Heart Association Scientist Development Grant (0830174N) and Penn State University.Contacts:
Krista Weidner | EurekAlert!
Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY
NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences