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!
Not of Divided Mind
19.01.2017 | Hertie-Institut für klinische Hirnforschung (HIH)
CRISPR meets single-cell sequencing in new screening method
19.01.2017 | CeMM Forschungszentrum für Molekulare Medizin der Österreichischen Akademie der Wissenschaften
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
19.01.2017 | Earth Sciences
19.01.2017 | Life Sciences
19.01.2017 | Physics and Astronomy