Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The nucleus: Not just a bag of chromosomes

17.02.2003


Educators and scientists should discard the idea that a cell’s nucleus is just a bag of chromosomes, according to Johns Hopkins’ cell biologist Kathy Wilson, Ph.D. In a Feb. 17 session at the annual meeting of the American Association for the Advancement of Science (AAAS) in Denver, Wilson and five others will introduce visual evidence of the nucleus’s newly recognized importance.


Frog Nuclei



"The old view is that the nucleus is simply a warehouse for chromosomes," says Wilson, associate professor of cell biology in the Johns Hopkins School of Medicine’s Institute for Basic Biomedical Sciences. "But new research and imaging techniques show that the nucleus is really the cell’s mothership, a crucial and very active source of information, support and control."

It’s not too surprising that the nucleus itself has been overshadowed by the easy-to-see reams of genetic material and the fascinatingly tiny machinery that loosens, prepares, reads and copies genes. But in the last 10 or 15 years, evidence has mounted that these interior processes are actively linked to the nucleus, not just randomly taking place inside it, says Wilson, also chair of the public information committee of the American Society for Cell Biology, which helped organize the session.


Wilson and others, for example, are investigating rope-like nuclear proteins called lamins, which form networks throughout the nucleus. A few years ago, scientists discovered that mutations in the gene for "A-type" lamins cause Emery-Dreifuss muscular dystrophy, the third most common of the muscle-wasting disorders.

"That changed everything," says Wilson. "Until then, it was difficult to get federal funding to study lamins -- they were seen as boring. However, once they were linked to a human disease, scientists inside and outside the field appreciated that these proteins are doing unexpected, unexplained things."

Subsequently, lamin A has been linked to five other diseases, affecting the skeleton, heart, brain and fat, notes Wilson.

Beyond lamins, there’s an emerging revolution in understanding cell division, says Wilson. While the general cycle is well understood -- chromosomes are copied and then pulled to opposite ends of the cell, and the cell splits in two -- the details are still fuzzy. For one, the chromosomes are inside the nucleus, but the machinery that pulls them to one side or the other is outside the nucleus.

"The nucleus itself has to disappear before the cell can divide, and everyone thought that it just fell apart," says Wilson. "But recent evidence shows that its breakdown is an orchestrated process similar to the pulling apart of the chromosomes. It seems to involve the same structures and the same tiny motors. It’s almost a practice run for moving the chromosomes."

Wilson notes that no college textbook yet reflects current understanding of the nucleus.

"Scientists studying the nucleus have just reached the point where we’ve discovered enough to talk about the bigger picture and how our seemingly separate areas overlap," she adds. "But it’s really important to develop an integrated view of the nucleus."

That’s one goal of the AAAS session, she notes. The scientists will present recent advances in six areas, including the disassembly of the nucleus during cell division, lamins, links between the nucleus and disease, implications of the "new" nucleus in gene therapy, and the structure and function of "pores" in the nuclear membrane. The best part of the session, Wilson says, is that there will be lots of "cool pictures."

In addition to Wilson, scheduled presenters are Andrew Belmont of the University of Illinois, Robert Goldman of Northwestern University School of Medicine, Howard Worman of Columbia University College of Physicians and Surgeons, Brian Burke of the University of Florida, and Douglass Forbes of the University of California at San Diego. Tim Richardson of the Toronto Hospital for Sick Children is producing video of various nuclear processes for the session.

Joanna Downer | EurekAlert!
Further information:
http://www.hopkinsmedicine.org/Images/images/frognuclei.jpg
http://www.aaas.org
http://www.ascb.org

More articles from Life Sciences:

nachricht Colorectal cancer: Increased life expectancy thanks to individualised therapies
20.02.2020 | Christian-Albrechts-Universität zu Kiel

nachricht Sweet beaks: What Galapagos finches and marine bacteria have in common
20.02.2020 | Max-Planck-Institut für Marine Mikrobiologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A step towards controlling spin-dependent petahertz electronics by material defects

The operational speed of semiconductors in various electronic and optoelectronic devices is limited to several gigahertz (a billion oscillations per second). This constrains the upper limit of the operational speed of computing. Now researchers from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg, Germany, and the Indian Institute of Technology in Bombay have explained how these processes can be sped up through the use of light waves and defected solid materials.

Light waves perform several hundred trillion oscillations per second. Hence, it is natural to envision employing light oscillations to drive the electronic...

Im Focus: Freiburg researcher investigate the origins of surface texture

Most natural and artificial surfaces are rough: metals and even glasses that appear smooth to the naked eye can look like jagged mountain ranges under the microscope. There is currently no uniform theory about the origin of this roughness despite it being observed on all scales, from the atomic to the tectonic. Scientists suspect that the rough surface is formed by irreversible plastic deformation that occurs in many processes of mechanical machining of components such as milling.

Prof. Dr. Lars Pastewka from the Simulation group at the Department of Microsystems Engineering at the University of Freiburg and his team have simulated such...

Im Focus: Skyrmions like it hot: Spin structures are controllable even at high temperatures

Investigation of the temperature dependence of the skyrmion Hall effect reveals further insights into possible new data storage devices

The joint research project of Johannes Gutenberg University Mainz (JGU) and the Massachusetts Institute of Technology (MIT) that had previously demonstrated...

Im Focus: Making the internet more energy efficient through systemic optimization

Researchers at Chalmers University of Technology, Sweden, recently completed a 5-year research project looking at how to make fibre optic communications systems more energy efficient. Among their proposals are smart, error-correcting data chip circuits, which they refined to be 10 times less energy consumptive. The project has yielded several scientific articles, in publications including Nature Communications.

Streaming films and music, scrolling through social media, and using cloud-based storage services are everyday activities now.

Im Focus: New synthesis methods enhance 3D chemical space for drug discovery

After helping develop a new approach for organic synthesis -- carbon-hydrogen functionalization -- scientists at Emory University are now showing how this approach may apply to drug discovery. Nature Catalysis published their most recent work -- a streamlined process for making a three-dimensional scaffold of keen interest to the pharmaceutical industry.

"Our tools open up whole new chemical space for potential drug targets," says Huw Davies, Emory professor of organic chemistry and senior author of the paper.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

70th Lindau Nobel Laureate Meeting: Around 70 Laureates set to meet with young scientists from approx. 100 countries

12.02.2020 | Event News

11th Advanced Battery Power Conference, March 24-25, 2020 in Münster/Germany

16.01.2020 | Event News

Laser Colloquium Hydrogen LKH2: fast and reliable fuel cell manufacturing

15.01.2020 | Event News

 
Latest News

Journey to the center of Mars

20.02.2020 | Physics and Astronomy

Laser writing enables practical flat optics and data storage in glass

20.02.2020 | Physics and Astronomy

New graphene-based metasurface capable of independent amplitude and phase control of light

20.02.2020 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>