Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Food for Thought: Cells Dine on Their Own Brains to Stay Fit and Trim

10.01.2003


Eating your own brain may not sound like a sensible approach to prolonging your life, but researchers at the University of Rochester have discovered that some single-celled organisms essentially do just that to keep themselves healthy. The findings are published in this month’s issue of Molecular Biology of the Cell.



David Goldfarb, professor of biology at the University of Rochester, studied the yeast Saccharomyces cerevisiae and found that contrary to what biologists have believed, the cell would "eat" its own nucleus to rid itself of aged or damaged sections. Though it’s long been known that cells frequently break down and recycle various cell parts in a process called autophagy (after the Greek for "self-eating"), biologists thought that eating the nucleus was strictly off-limits. The nucleus, after all, is sort of the control center of the cell, and where the cell stores its most precious possessions such as its DNA. Eating it would be a bit like lunching on your own brain.

Goldfarb, however, found that the yeast can eat its nucleus by taking it apart piece by piece, removing non-essential bits and leaving behind the essential components such as the chromosomes.


"In human society, the business of collecting and recycling garbage isn’t a very glamorous enterprise, but in the less prestige-oriented world of cells, it’s invaluable," says Goldfarb. "We now know just how critical this process is, since a unique and elegant autophagic mechanism evolved to allow the piecemeal degradation of an otherwise essential organelle."

Autophagy is really a family of related processes that identify and deliver useful organic molecules, called macromolecules, to the cell’s lysozymes or vacuoles. Lysozymes and vacuoles are much like our own stomachs, filled with acid and hydrolytic enzymes capable of reducing macromolecules to their minimal parts. These parts are then shuttled where they are used either to stoke the metabolic fires or as building materials for new macromolecules. The only part of the cell thought to escape this fate is the nucleus, which is as essential to a cell as our brains are to us. Biologists had always thought that taking a bite out of the nucleus would effectively end a cell’s life.

Goldfarb found that when the yeast cell wants to recycle some of the macromolecules from its nucleus, it sends a vacuole to pinch off a teardrop-shaped portion of the nucleus and "digest" it. This unique process, called piecemeal microautophagy of the nucleus (PMN), occurs at Velcro-like junctions between the vacuole and the nuclear membranes. Nucleus-vacuole junctions were first described in 2000 by the Rochester group and remain the best-understood, inter-organellar junction apparatus in nature.

"It’s possible that PMN may not only recycle damaged or useless portions of the nucleus," says Goldfarb. "It’s possible that PMN increases the life span of yeast cells which, like humans, age and die."

Although it’s unknown if PMN is at work in human cells, there are a number of cases such as Bloom’s disease where pieces of human nuclei are pinched off into the cytoplasm. Scientists have no idea how or why this happens, but the new findings could provide an important foundation on which to build an understanding.

This research was funded by the National Science Foundation and the National Institutes of Health.

Jonathan Sherwood | EurekAlert!
Further information:
http://www.rochester.edu/pr/News/NewsReleases/scitech/goldfarb-autophagy.html

More articles from Life Sciences:

nachricht NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation

nachricht Pollen taxi for bacteria
18.07.2018 | Technische Universität München

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

NYSCF researchers develop novel bioengineering technique for personalized bone grafts

18.07.2018 | Life Sciences

Machine-learning predicted a superhard and high-energy-density tungsten nitride

18.07.2018 | Materials Sciences

Why might reading make myopic?

18.07.2018 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>