Tandem Fix For Badly Folded Proteins

Diseases associated with a loss of protein function often arise when a mutation prevents the relevant protein from folding properly and performing efficiently. Researchers at Scripps Research Institute have now devised a method that sufficiently improves the folding of mutant proteins to restore their function (Cell 2008, 134, 769). Jeffery W. Kelly, Laura Segatori (now at Rice University), and colleagues carried out the work with cells cultured from Tay-Sachs and Gaucher's disease patients. They first determined that compounds such as celastrol improve the folding and function of mutant proteins in the cells. These "proteostasis modulators" enhance the cells' normal protein-folding activity by increasing production of chaperone proteins and folding enzymes. The team then showed that proteostasis modulators work even better when combined with small molecules known as "pharmacologic chaperones," such as N-(n-nonyl)-deoxynojirimycin (NN-DNJ). The two types of compounds act synergistically to stabilize the mutant protein in its properly folded state. Such compounds could be used as the basis for oral treatments for a number of diseases marked by misfolding proteins, Segatori says.