Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists map the portal to the cell's nucleus

16.03.2018

Like an island nation, the nucleus of a cell has a transportation problem. Evolution has enclosed it with a double membrane, the nuclear envelope, which protects DNA but also cuts it off from the rest of the cell. Nature's solution is a massive--by molecular standards--cylindrical configuration known as the nuclear pore complex, through which imports and exports travel, connecting the bulk of the cell with its headquarters.

In research described March 14 in Nature, scientists at Rockefeller University and their colleagues have delineated the architecture of the nuclear pore complex in yeast cells. The biological blueprint they uncovered shares principles sometimes seen on a much larger scale in concrete, steel, and wire.


A map showing how the 552 pieces of the pore complex fit together could inform research into numerous diseases.

Credit: The Rockefeller University

Usage Restrictions: Video may be used only to illustrate the research described in the accompanying release.

"It reminds us of a suspension bridge, in which a combination of sturdy and flexible parts produce a stress-resilient structure," says Michael P. Rout, who led the work together with Brian T. Chait.

The pore complex contains 552 component proteins, called nucleoporins, and scientists hadn't previously known how they all fit together. It took a combination of approaches to assemble a comprehensive map of these pieces. The researchers hope this new molecular structure will enable new studies of how the nuclear portal functions normally, and how defects in it lead to diseases such as cancer.

A milestone

The pore complex first emerged when single-celled organisms--the only living things at the time--acquired special compartments containing organ-like structures, including the nucleus, which houses the cell's genetic code.

It serves not only as a conduit to and from the nucleus, but also as a checkpoint regulating what passes in and out. Genetic instructions transcribed into RNA are allowed to exit, for example, while proteins needed inside the nucleus may enter. Other things, such as viruses bent on taking over the cell, are kept at bay.

Rout and Chait began mapping this ancient structure more than 20 years ago, knowing the project could well span decades since the target of their curiosity is not easily defined.

More than a third of the pore complex can move about, and this flexibility, along with the structure's immense size and the constant stream of traffic passing through it, meant that no single approach to mapping it would work. "In the end, we used everything we could lay our hands on, brought the results together, and integrated them into a single structure," says Chait, who is Rockefeller's Camille and Henry Dreyfus Professor.

Together with researchers at the University of California, San Francisco; Boston University Medical School; and Baylor College of Medicine, the team was able to determine the type and amount of each nucleoporin and their proximities to one another, as well as the weight and shape of the whole complex.

This data allowed them to visualize the anatomy of many of the individual pore components and to place them all within the pore complex. They uncovered a complicated ringed structure containing rigid, diagonal columns and flexible connectors that evoke the towers and cables of human-made structures like the Golden Gate Bridge.

The resulting map is a breakthrough in a line of investigation with a deep Rockefeller history. The pore complex first came into human view in the 1950s, when a university scientist, Michael Watson, observed small densities dotting the surface of the nuclear envelope. And about two decades later, the lab of Günter Blobel, who passed away last month, was among the first to discover individual nups and then determine their structure.

A new starting point

When it comes to the pore complex, yeast has a considerable amount in common with us. When the team compared their data with structural findings from human pore complexes, they found similar elements arranged somewhat differently. The resemblance suggests the yeast pore complex could be useful for research relevant to humans.

And there's a lot of such research to be done. Defects in the pore complex and its components have been linked to a host of diseases, including autoimmune disorders and cancer; meanwhile, viruses have evolved ways to sneak past it altogether. But the details of these malfunctions and blind spots are often obscure.

The new yeast structure may help. With it, the team found they could map sites that are altered in some cancers--evidence, they say, that the yeast pore complex can be used to test how factors like stress, drugs, or mutations change the human structure, and so aiding efforts to understand and treat disease.

Media Contact

Katherine Fenz
kfenz@rockefeller.edu
212-327-7913

 @rockefelleruniv

http://www.rockefeller.edu 

Katherine Fenz | EurekAlert!

More articles from Life Sciences:

nachricht Quality control in immune communication: Chaperones detect immature signaling molecules in the immune system
20.09.2019 | Technische Universität München

nachricht Moderately Common Plants Show Highest Relative Losses
20.09.2019 | Universität Rostock

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: 'Nanochains' could increase battery capacity, cut charging time

How long the battery of your phone or computer lasts depends on how many lithium ions can be stored in the battery's negative electrode material. If the battery runs out of these ions, it can't generate an electrical current to run a device and ultimately fails.

Materials with a higher lithium ion storage capacity are either too heavy or the wrong shape to replace graphite, the electrode material currently used in...

Im Focus: Stevens team closes in on 'holy grail' of room temperature quantum computing chips

Photons interact on chip-based system with unprecedented efficiency

To process information, photons must interact. However, these tiny packets of light want nothing to do with each other, each passing by without altering the...

Im Focus: Happy hour for time-resolved crystallography

Researchers from the Department of Atomically Resolved Dynamics of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg, the University of Hamburg and the European Molecular Biology Laboratory (EMBL) outstation in the city have developed a new method to watch biomolecules at work. This method dramatically simplifies starting enzymatic reactions by mixing a cocktail of small amounts of liquids with protein crystals. Determination of the protein structures at different times after mixing can be assembled into a time-lapse sequence that shows the molecular foundations of biology.

The functions of biomolecules are determined by their motions and structural changes. Yet it is a formidable challenge to understand these dynamic motions.

Im Focus: Modular OLED light strips

At the International Symposium on Automotive Lighting 2019 (ISAL) in Darmstadt from September 23 to 25, 2019, the Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, a provider of research and development services in the field of organic electronics, will present OLED light strips of any length with additional functionalities for the first time at booth no. 37.

Almost everyone is familiar with light strips for interior design. LED strips are available by the metre in DIY stores around the corner and are just as often...

Im Focus: Tomorrow´s coolants of choice

Scientists assess the potential of magnetic-cooling materials

Later during this century, around 2060, a paradigm shift in global energy consumption is expected: we will spend more energy for cooling than for heating....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Optical Technologies: International Symposium „Future Optics“ in Hannover

19.09.2019 | Event News

Society 5.0: putting humans at the heart of digitalisation

10.09.2019 | Event News

Interspeech 2019 conference: Alexa and Siri in Graz

04.09.2019 | Event News

 
Latest News

Quality control in immune communication: Chaperones detect immature signaling molecules in the immune system

20.09.2019 | Life Sciences

Moderately Common Plants Show Highest Relative Losses

20.09.2019 | Life Sciences

The Fluid Fingerprint of Hurricanes

20.09.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>