Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Well-known protein reveals new tricks

UCSF study shows clathrin protein moonlights, playing key role in cell division

A protein called "clathrin," which is found in every human cell and plays a critical role in transporting materials within them, also plays a key role in cell division, according to new research at the University of California, San Francisco.

The discovery, featured on the cover of the Journal of Cell Biology in August, sheds light on the process of cell division and provides a new angle for understanding cancer. Without clathrin, cells divide erratically and unevenly—a phenomenon that is one of the hallmarks of the disease.

"Clathrin is doing more than we thought it was doing," said Frances Brodsky, DPhil, who led the research. Brodsky is a professor in the UCSF Department of Bioengineering and Therapeutic Sciences, a joint department of the Schools of Pharmacy and Medicine, and she holds joint appointments in Microbiology and Immunology, as well as Pharmaceutical Chemistry.

A Protein Essential for Transportation in More Than One Route

Akin to a three-pronged building block in a child's construction set, clathrin can provide links to create larger complexes. When lots of these proteins are assembled together, they can form tough little cages into which cells packs many of their essential biological molecules—hormones, neurotransmitters, membrane proteins and other payloads that need to be transported throughout the cell.

Once thought to be solely involved in transport inside cells, scientists have uncovered more and more of the protein's hidden functions in the last half-dozen years, including some roles it plays in cell division.

For instance, they learned several years ago about its role in the function of "spindles." Normally when a cell divides, it forms a spindle by laying down tracks of structural proteins, and uses them as scaffolding to separate the cell's DNA (in the form of chromosomes) into two equal collections—one identical set of DNA for each of the new daughter cells. Scientists found that clathrin is involved in stabilizing these spindles.

Now, however, Brodsky and her colleagues have shown that clathrin does even more. They deleted clathrin from cells using a technique called RNA interference, which involves infusing in small genetic fragments that block the cell from making the clathrin. Doing so, Brodsky and her colleagues showed that clathrin stabilizes the structures in dividing cells known as centrosomes.

Tagged with fluorescent chemicals and viewed under a microscope, the centrosomes within a cell that is about to divide look like two glowing eyes peering through the dark. But without clathrin, the team determined, the eyes increase in number.

Brodsky and her colleagues traced this effect to a protein complex formed by one particular component of clathrin called CHC17, which directly stabilizes the centrosome and helps it mature. Deleting CHC17 or chemically inactivating it, led to cells with a strange appearance. These cells contained multiple, fragmented centrosomes instead of the normal two and built abnormal spindles.

This discovery may reveal pathways towards abnormalities of chromosome segregation associated with cancer, said Brodsky.

The article, "Clathrin promotes centrosome integrity in early mitosis through stabilization of centrosomal ch-TOG" by Amy B. Foraker, Stéphane M. Camus, Timothy M. Evans, Sophia R. Majeed, Chih-Ying Chen, Sabrina B. Taner, Ivan R. Corrêa Jr., Stephen J. Doxsey and Frances M. Brodsky appears in the August 20, 2012 issue of the Journal of Cell Biology. See:

In addition to the group at UCSF, authors on this study are affiliated with New England Biolabs, Inc., in Ipswich, MA, and the University of Massachusetts Medical School in Worcester, MA.

Jason Socrates Bardi | EurekAlert!
Further information:

Further reports about: CHC17 DNA UCSF cell death cell division synthetic biology

More articles from Life Sciences:

nachricht Make way for the mini flying machines
21.03.2018 | American Chemical Society

nachricht New 4-D printer could reshape the world we live in
21.03.2018 | American Chemical Society

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Researchers at Fraunhofer monitor re-entry of Chinese space station Tiangong-1

In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.

Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...

Im Focus: Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.

They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...

Im Focus: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

Im Focus: Tiny implants for cells are functional in vivo

For the first time, an interdisciplinary team from the University of Basel has succeeded in integrating artificial organelles into the cells of live zebrafish embryos. This innovative approach using artificial organelles as cellular implants offers new potential in treating a range of diseases, as the authors report in an article published in Nature Communications.

In the cells of higher organisms, organelles such as the nucleus or mitochondria perform a range of complex functions necessary for life. In the networks of...

Im Focus: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

Latest News

TRAPPIST-1 planets provide clues to the nature of habitable worlds

21.03.2018 | Physics and Astronomy

The search for dark matter widens

21.03.2018 | Materials Sciences

Natural enemies reduce pesticide use

21.03.2018 | Life Sciences

Science & Research
Overview of more VideoLinks >>>