Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Where the Fat’s At

27.08.2010
In real estate, location is everything. The same might be said of lipids – those crucial cellular fats and oils that serve as building blocks for cells and as key energy sources for the body.

In a paper published in the September issue of the Journal of Lipid Research, a team of scientists, led by researchers at the University of California, San Diego School of Medicine, has mapped for the first time the actual locations of specific lipids within a single cell.

“This is groundbreaking analysis,” said Edward A. Dennis, PhD, distinguished professor of pharmacology, chemistry and biochemistry at UC San Diego and principal investigator of LIPID MAPS, a national consortium studying the structure and function of lipids. “We’ve defined not only which lipids are within a particular cell, but also where these lipids are located. That’s important because lipids do different things in a cell. They’re vital components of membranes. They’re involved in communications and signaling, both within cells and between cells. Where they are located – in a cell’s nucleus, its mitochondria, membrane or other organelle – is relevant to their function.”

And because most serious diseases are linked to specific organelle dysfunction, understanding what lipids do at the subcellular level is essential to elucidating how diseases ranging from atherosclerosis and arthritis to cancer and diabetes work – and how they might be better treated or prevented.

The focus of the lipid mapping was a cultured mouse macrophage or white blood cell, said Dennis, who also serves as editor-in-chief of the Journal of Lipid Research. Alexander Andreyev, PhD, a project scientist in the Dennis lab, extracted and separated organelles of the macrophage using advanced subcellular fractionation techniques. Scientists at collaborating universities then precisely identified and quantified the major lipid categories present with mass spectrometry. More than 220 individual molecular lipid species were identified and analyzed.

The analyses were conducted on macrophages in both resting and activated stages, the latter induced by exposing the cells to a specially synthesized chemical similar to a molecule found in bacteria pathogens. Called KLA, the chemical provokes a signaling cascade inside macrophages, activating their immune system response to infections.

“The idea was to see where targeted lipids were in macrophages at rest and how this changed upon infection,” said Dennis. “We discovered that numerous lipids change in abundance in the membrane and in organelles once a macrophage becomes active.”

Identifying these changes in specific lipids is expected to provide scientists with a deeper, more sophisticated understanding of how fats are involved in and influence disease processes, said Dennis.

“We’ve created a new picture of what’s happening in cells. Not an image, but a view at the molecular level where drugs interact and diseases are cured.”

The findings are part of the larger, on-going LIPID MAPS project, which received a second five-year renewal grant in 2008 for almost $38 million. The LIPID MAPS project is, in some ways, akin to the earlier Human Genome Project to inventory genes and similar endeavors with proteins (proteomics) and metabolites (metabolomics). It brings together researchers in a dozen research laboratories at nine universities, medical research institutes and life sciences companies. UC San Diego serves as lead institution and information clearinghouse.

“We’ve now identified many hundreds of lipids,” said Dennis, “but we have the capability of detecting many thousands. This has been a trail-blazing experiment. We can now go deeper into the cell.”

Co-authors of the study are Eoin Fahy, Xiang Li, Yihua Zhao and Shankar Subramaniam, San Diego Supercomputing Center, UC San Diego; Ziqiang Guan, Andrea Ryan and Christian R.H. Raetz, Department of Biochemistry, Duke University Medical Center; Samuel Kelly, Hyejung Park, Elaine Wang and Alfred Merrill, School of Biology, Georgia Institute of Technology; Jeffrey G. McDonald, Bonne M. Thompson and David W. Russell, University of Texas Southwestern Medical Center; and Steven Milne, David Myers and H. Alex Brown, Department of Pharmacology, Vanderbilt University.

Scott LaFee | Newswise Science News
Further information:
http://www.ucsd.edu

More articles from Life Sciences:

nachricht Megakaryocytes act as „bouncers“ restraining cell migration in the bone marrow
16.07.2019 | Rudolf-Virchow-Zentrum für Experimentelle Biomedizin der Universität Würzburg

nachricht A human liver cell atlas
15.07.2019 | Max Planck Institute of Immunobiology and Epigenetics

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Megakaryocytes act as „bouncers“ restraining cell migration in the bone marrow

Scientists at the University Würzburg and University Hospital of Würzburg found that megakaryocytes act as “bouncers” and thus modulate bone marrow niche properties and cell migration dynamics. The study was published in July in the Journal “Haematologica”.

Hematopoiesis is the process of forming blood cells, which occurs predominantly in the bone marrow. The bone marrow produces all types of blood cells: red...

Im Focus: Artificial neural network resolves puzzles from condensed matter physics: Which is the perfect quantum theory?

For some phenomena in quantum many-body physics several competing theories exist. But which of them describes a quantum phenomenon best? A team of researchers from the Technical University of Munich (TUM) and Harvard University in the United States has now successfully deployed artificial neural networks for image analysis of quantum systems.

Is that a dog or a cat? Such a classification is a prime example of machine learning: artificial neural networks can be trained to analyze images by looking...

Im Focus: Extremely hard yet metallically conductive: Bayreuth researchers develop novel material with high-tech prospects

An international research group led by scientists from the University of Bayreuth has produced a previously unknown material: Rhenium nitride pernitride. Thanks to combining properties that were previously considered incompatible, it looks set to become highly attractive for technological applications. Indeed, it is a super-hard metallic conductor that can withstand extremely high pressures like a diamond. A process now developed in Bayreuth opens up the possibility of producing rhenium nitride pernitride and other technologically interesting materials in sufficiently large quantity for their properties characterisation. The new findings are presented in "Nature Communications".

The possibility of finding a compound that was metallically conductive, super-hard, and ultra-incompressible was long considered unlikely in science. It was...

Im Focus: Modelling leads to the optimum size for platinum fuel cell catalysts: Activity of fuel cell catalysts doubled

An interdisciplinary research team at the Technical University of Munich (TUM) has built platinum nanoparticles for catalysis in fuel cells: The new size-optimized catalysts are twice as good as the best process commercially available today.

Fuel cells may well replace batteries as the power source for electric cars. They consume hydrogen, a gas which could be produced for example using surplus...

Im Focus: The secret of mushroom colors

Mushrooms: Darker fruiting bodies in cold climates

The fly agaric with its red hat is perhaps the most evocative of the diverse and variously colored mushroom species. Hitherto, the purpose of these colors was...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on UV LED Technologies & Applications – ICULTA 2020 | Call for Abstracts

24.06.2019 | Event News

SEMANTiCS 2019 brings together industry leaders and data scientists in Karlsruhe

29.04.2019 | Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

 
Latest News

Flying Laptop satellite mission extended by two years - Successfully in orbit since July 14, 2017

16.07.2019 | Physics and Astronomy

New safer, inexpensive way to propel small satellites

16.07.2019 | Power and Electrical Engineering

UCI electrical engineering team develops 'beyond 5G' wireless transceiver

16.07.2019 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>