Howard Hughes Medical Institute researchers have provided the
first detailed look at the core structure of the abnormal
protein filaments found in at least 20 devastating diseases,
ranging from Alzheimer's to Creutzfeldt-Jakob disease, the human
version of "mad cow" disease. The images reveal that the
filaments form a short zipper that is closed and stuck. To get a
more realistic picture of what the fibrils look like, however,
one should picture a towering stack of zippers, each of which is
tightly bonded to the one below. The first atomic details of the
interconnected protein segments were reported in the June 9,
2005, issue of Nature. In each disease, a different protein
transforms into the misfolded threads known as amyloid fibrils.
Scientists believe that the various proteins share a common
underlying feature that explains how they assemble into the
persistent fibrils that can accumulate in the brain and other
tissues. "To do something about these diseases, you have be able
to see the parts at the atomic