Huntington's disease causes progressive neurological damage. Symptoms first appear in mid-life and gradually rob patients of their ability to talk, walk, think or even swallow. The disease is caused by an inherited mutation in the polyglutamine region of a protein called huntingtin. In a first phase of research, scientists at UC Irvine showed that two amino acids near the beginning of the huntingtin protein can be altered by a chemical process called phosphorylation. The UCLA researchers then tested whether phosphorylation could influence the disease process. Using two mouse models with the Huntington's disease mutation, they modified the two amino acids in different ways -- one to mimic phosphorylation and one to prevent it.
They found that preventing phosphorylation caused the mice to develop symptoms of the disease but mimicking it did not. Similar research, performed at the University of Pittsburgh, has also shown that mimicking phosphorylation of a fragment of the huntingtin gene reduces the protein's tendency to form clumps.
"We were surprised to find that subtle modification of only two amino acids in this very large protein can prevent the onset of disease," the lead author of the study, X. William Yang, said in a news release.
-- Shari Roan
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