Since 1998, research into the disease has focused on the protein Parkin, made by a gene on chromosome 6, because this gene is mutated in most people with a rare form called juvenile Parkinson's and in about 40 per cent of adult Parkinson's sufferers.

Now, Ryosuke Takahashi and colleagues have found a protein that couples to Parkin and that could explain why Parkin is important to neuron cell survival, they report in today's Cell.

Takahashi, of RIKEN Brain Science Institute in Japan, and colleagues screened libraries of human DNA to find proteins that bound to Parkin, and found Pael receptor, a transmembrane polypeptide.

They then overexpressed Pael receptor in human neurons and found that it unfolded and came out of solution, causing cell death. The same thing happened in cells with mutated Parkin, suggesting a role for Parkin in eliminating misfolded Pael receptor molecules.

The group also found high levels of Pael-R in the brains of people who had died from juvenile Parkinson's.

This suggests an important link among Parkinson's, Alzheimer's and other neurodegenerative diseases such as variant CJD, the human form of mad cow disease, in that all are associated with accumulation of misfolded proteins in the brain.

[Contact: Ryosuke Takahashi]

29-Jun-2001