NEW YORK (Reuters Health) Oct 01 - Mutations in the genes for HtrA2,
a serine protease, and PINK1, a protein kinase, have been linked to
Parkinson's disease, and now new research shows that the proteins
interact to regulate mitochondrial function.

As reported in the September 30th online issue of Nature Cell
Biology, Dr. Julian Downward, from Cancer Research UK in London, and
colleagues found that PINK1 regulates HtrA2. Moreover, they show
that when a cell is exposed to stress, PINK1 is needed for the
mitochondrial protection conferred by HtrA2.

Testing of brain samples from Parkinson's patients with PINK1
mutations revealed that the interactivity with HtrA2 is impaired.

"The characterization of this mitochondrial stress-responsive
pathway involving HtrA2 and PINK1 in neurodegeneration in humans
will lead to an improved understanding of the pathogenesis of
Parkinson's disease, and ultimately, possibly to novel therapeutic
approaches," the authors conclude.

Nat Cell Biol 2007