Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Zinc, proteins, and an essential cellular balancing act

01.10.2013
Scientists at the University of Wisconsin-Madison have made a discovery that, if replicated in humans, suggests a shortage of zinc may contribute to diseases like Alzheimer's and Parkinson's, which have been linked to defective proteins clumping together in the brain.

With proteins, shape is everything. The correct shape allows some proteins to ferry atoms or molecules about a cell, others to provide essential cellular scaffolding or identify invading bacteria for attack. When proteins lose their shape due to high temperature or chemical damage, they stop working and can clump together — a hallmark of Parkinson's and Alzheimer's.

The UW researchers have discovered another stress that decreases protein stability and causes clumping: a shortage of zinc, an essential metal nutrient.

Zinc ions play a key role in creating and holding proteins in the correct shape. In a study just published in the online Journal of Biological Chemistry, Colin MacDiarmid and David Eide show that the gene Tsa1 creates "protein chaperones" that prevent clumping of proteins in cells with a zinc shortage. By holding proteins in solution, Tsa1 prevents damage that can otherwise lead to cell death.

... more about:
»Alzheimer »Parkinson »human cell »zinc

For simplicity, the researchers studied the system in yeast — a single-celled fungus. Yeast can adapt to both shortages and excesses of zinc, says MacDiarmid, an associate scientist. "Zinc is an essential nutrient but if there's too much, it's toxic. The issue for the cell is to find enough zinc to grow and support all its functions, while at the same time not accumulating so much that it kills the cell."

Cells that are low in zinc also produce proteins that counter the resulting stress, including one called Tsa1.

The researchers already knew that Tsa1 could reduce the level of harmful oxidants in cells that are short of zinc. Tsa1, MacDiarmid says, "is really a two-part protein. It can get rid of dangerous reactive oxygen species that damage proteins, but it also has this totally distinct chaperone function that protects proteins from aggregating. We found that the chaperone function was the more important of the two."

"In yeast, if a cell is deficient in zinc, the proteins can mis-fold, and Tsa1 is needed to keep the proteins intact so they can function," says Eide, a professor of nutritional science. "If you don't have zinc, and you don't have Tsa1, the proteins will glom together into big aggregations that are either toxic by themselves, or toxic because the proteins are not doing what they are supposed to do. Either way, you end up killing the cell."

While the medical implications remain to be explored, there are clear similarities between yeast and human cells. "Zinc is needed by all cells, all organisms, it's not just for steel roofs, nails and trashcans," Eide says. "The global extent of zinc deficiency is debated, but diets that are high in whole grains and low in meat could lead to deficiency."

If low zinc supply has the same effect on human cells as on yeast, zinc deficiency might contribute to human diseases that are associated with a build-up of "junked" proteins, such as Parkinson's and Alzheimer's. Eide says a similar protective system to Tsa1 also exists in animals, and the research group plans to move ahead by studying that system in human cell culture.

David Tenenbaum, 608-265-8549, djtenenb@wisc.edu

Colin MacDiarmid | EurekAlert!
Further information:
http://www.wisc.edu

Further reports about: Alzheimer Parkinson human cell zinc

More articles from Life Sciences:

nachricht What the world's tiniest 'monster truck' reveals
23.08.2017 | American Chemical Society

nachricht Treating arthritis with algae
23.08.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

ShAPEing the future of magnesium car parts

23.08.2017 | Automotive Engineering

New insights into the world of trypanosomes

23.08.2017 | Life Sciences

New Test for Rare Immunodeficiency

23.08.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>