The closest look ever at native human tissue

Seeing proteins in their natural environment and interactions inside cells has been a long-standing goal. Using an advanced microscopy technique called cryo-electron tomography, researchers from the European Molecular Biology Laboratory [EMBL] have visualised proteins responsible for cell-cell contacts for the first time. In this week’s issue of Nature they publish the first 3D image of human skin at molecular resolution and reveal the molecular Velcro-like organisation that interlinks cells.

“This is a real breakthrough in two respects,” says Achilleas Frangakis, group leader at EMBL. “Never before has it been possible to look in three dimensions at a tissue so close to its native state at such a high resolution. We can now see details at the scale of a few millionths of a millimetre. In this way we have gained a new view on the interactions of molecules that underlie cell adhesion in tissues – a mechanism that has been disputed over decades.”

So far, the only information available about a protein’s position and interactions in a cell was based on either light microscopy images at poor resolution or techniques that remove proteins from their natural context. Frangakis and his group have been developing a technique called cryo-electron tomography, with which a cell or tissue is instantly frozen in its natural state and then examined with an electron micro-scope. Electron microscopy normally requires tissue to be treated with chemicals or coated in metal, a procedure that disturbs the natural state of a sample. With cyro-electron tomography, images are taken of the untreated sample from different directions and assembled into an accurate 3D image by a computer.

The researchers applied this technique to observe proteins that are crucial for the integrity of tissues and organs like the skin and the heart, but also play an important role in cell proliferation. These proteins, called cadherins, are anchored in cell membranes and interact with each other to bring cells close together and interlink them tightly.

“We could see the interaction between two cadherins directly, and this revealed where the strength of human skin comes from,” says Ashraf Al-Amoudi, who carried out the work in Frangakis’ lab. “The trick is that each cadherin binds twice: once to a molecule from the juxtaposed cell, and once to its next-door neighbour. The system works a bit like specialised Velcro and establishes very tight contacts between cells.”

The new insights into the cadherin system broadens the understanding of structural aspects of cell adhesion and shed light on other crucial processes such as cell proliferation. The technical advances achieved in cryo-electron tomography of frozen sections open up new possibilities to study more systems at native conditions with molecular resolution.

Anna-Lynn Wegener
Press Officer
EMBL
Meyerhofstrasse 1
D-69117 Heidelberg
tel. +49-6221-3878452
fax +49-6221-387525
wegener@embl.de

Media Contact

Anna-Lynn Wegener EMBL

More Information:

http://www.embl.de

All latest news from the category: Life Sciences and Chemistry

Articles and reports from the Life Sciences and chemistry area deal with applied and basic research into modern biology, chemistry and human medicine.

Valuable information can be found on a range of life sciences fields including bacteriology, biochemistry, bionics, bioinformatics, biophysics, biotechnology, genetics, geobotany, human biology, marine biology, microbiology, molecular biology, cellular biology, zoology, bioinorganic chemistry, microchemistry and environmental chemistry.

Back to home

Comments (0)

Write a comment

Newest articles

Lighting up the future

New multidisciplinary research from the University of St Andrews could lead to more efficient televisions, computer screens and lighting. Researchers at the Organic Semiconductor Centre in the School of Physics and…

Researchers crack sugarcane’s complex genetic code

Sweet success: Scientists created a highly accurate reference genome for one of the most important modern crops and found a rare example of how genes confer disease resistance in plants….

Evolution of the most powerful ocean current on Earth

The Antarctic Circumpolar Current plays an important part in global overturning circulation, the exchange of heat and CO2 between the ocean and atmosphere, and the stability of Antarctica’s ice sheets….

Partners & Sponsors