Mutant Protein in Huntington's Disease may Be Destroyed by New Tool

A so-called intrabody tool that may help in destroying the mutant protein responsible for Huntington's disease has been developed by researchers from Emory University.

They engineered a virus to make an intracellular antibody or "intrabody" against huntingtin, the protein whose mutant forms damage brain cells of people with Huntington's.

When they injected the virus into the mice's brains that make mutant huntingtin improved their ability to move their limbs, although it does not prolong their lives.

Xiao-Jiang Li, PhD, senior author and professor of human genetics at Emory University School of Medicine said that though other researchers have shown that various intrabodies can protect cells from mutant huntingtin, their team was the first to examine the effects of an intrabody in living mice.

"Our goal here was to create a tool that could distinguish between the accumulation of mutant proteins in the nucleus and the cytoplasm," he said.

"The intrabody binds huntingtin proteins with expanded poly-glutamine regions and it only works in the cytoplasm, not the nucleus."

Mutant proteins have a region consisting of the same amino acid (glutamine) many times, called poly-glutamine, which makes the proteins clump together inside brain cells.

The study showed that cultured cells that make both the intrabody and mutant huntingtin are able to get rid of the mutant protein faster and have fewer clumps of huntingtin.

"Several neurodegenerative diseases appear to involve defects in protein folding and metabolism, leading to the accumulation of protein aggregates inside cells," he said.

"Our study suggests a strategy for dissecting the harmful effects of these protein aggregates in other diseases," he added.

The study appears online and is scheduled for publication in the May/June issue of the Journal of Cell Biology.

Source-ANI
RAS/L