From the ArcaMax Publishing, Science & Technology Newsletter:
http://www.arcamax.com/news/technology/s-347362-484533
WALTHAM, Mass. (UPI) -- U.S. and German scientists say they've created
a three-dimensional picture of an Alzheimer's disease peptide using
electron microscopy.
Researchers at Brandeis University in Massachusetts and the Leibniz
Institute in Jena, Germany, say their achievement is "an important
step toward demystifying the role protein clumps play in the
development of neurodegenerative disease."
The study marks the first time scientists have shown how A-beta
peptides, found in the brains of Alzheimer's patients, form a
spaghetti-like protein mass called an amyloid fibril.
"This study is a significant advance regarding our understanding of
how fibrils are built from the A-beta peptide," said co-author
Nikolaus Grigorieff, a biophysicist at Brandeis University. "People
have been guessing for decades what these fibrils look like, but now
we have an actual 3D image."
In healthy people A-beta peptide doesn't aggregate, but in Alzheimer's
patients it clumps first and then forms long fibrils, like tentacles,
said Grigorieff. Scientists disagree whether it's the clumps that kill
brain neurons or the fibrils. Grigorieff wants to discover which part
of the amyloid structure is toxic -- a step necessary to designing
drugs to prevent or treat the disease.
The study appears in the Proceedings of the National Academy of
Sciences.