Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New Trick Found for How Cells Stay Organized

16.01.2015

Unique boundary found for little-known cellular compartment

Fast Facts:


Jenn Wang

As time passes (left to right), RNA granules (green dots) segregate to the posterior of a newly fertilized C. elegans egg. Chromosomes are marked in red.

  • RNA granules are tiny cellular compartments that are not bound by membranes like most other compartments.
  • They were thought to not need a physical boundary, but they do.
  • The boundary is a new type that resembles an irregularly shaped protein cage that revolves around the contents of the granule.

Organization is key to an efficient workplace, and cells are no exception to this rule. New evidence from Johns Hopkins researchers suggests that, in addition to membranes, cells have another way to keep their contents and activities separate: with ribbons of spinning proteins. A summary of their findings appears today in the journal eLife.

Each cell is a busy warehouse of activity. To keep things orderly, protein workers are “assigned” to specific areas of the cell where other workers are collaborating on the same project. Most of the project areas, or organelles, in the cell are cordoned off by flexible membranes that let things in and out on an as-needed basis, but some organelles, like RNA granules, do not seem to have clear boundaries.

RNA granules float throughout the watery space inside the cell and are responsible for transporting, storing and controlling RNA — DNA’s chemical cousin — which holds blueprints for proteins. Until now, researchers thought that the granules didn’t have concrete edges to separate them from the space outside.

“Before, the thinking was that RNA granules were like oil in water,” says Geraldine Seydoux, Ph.D., a Howard Hughes investigator and professor of molecular biology and genetics at the Johns Hopkins University School of Medicine. “Oil molecules create droplets because they are attracted to themselves, and so they are able to separate from surrounding water. Now we know that the separation of RNA granules from their watery surroundings is facilitated by a dynamic envelope that stabilizes them.”

Seydoux and her team worked with Eric Betzig, Ph.D., of Janelia Farm, who uses a state-of-the-art microscope that can detect rapidly moving particles. That microscope was key to detecting the irregularly shaped protein “cages” that surround the granules because they are constantly orbiting. When the researchers identified the proteins that create the cages, they were further surprised to find that the proteins are predicted not to interact with RNA and are rarely folded as most proteins are.

Seydoux says there are many questions left open about the nature of these protein cages and the RNA granules they surround, but “it is quite exciting to have discovered a new way that cells organize their contents.”

Other authors of the report include Jennifer Wang, Jarrett Smith, Helen Schmidt, Dominique Rasoloson, Alexandre Paix, Bramwell Lambrus and Deepika Calidas of the Johns Hopkins University School of Medicine, as well as Bi-Chang Chen of Janelia Farm.

This work was supported by the National Institute of Child Health and Human Development (R01HD37047) and the Howard Hughes Medical Institute.

Citations: eLife, Jan-2015; R01HD37047

Contact Information
Catherine Kolf
Senior Communications Specialist
ckolf@jhmi.edu
Phone: 443-287-2251
Mobile: 443-440-1929

Catherine Kolf | newswise

More articles from Life Sciences:

nachricht The birth of a new protein
20.10.2017 | University of Arizona

nachricht Building New Moss Factories
20.10.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>