Dysregulation of gene expression in the R6/2 model of polyglutamine disease: parallel changes in muscle and brain.

Previous analyses of gene expression in a mouse model of Huntington's disease (R6/2) indicated that an N-terminal fragment of mutant huntingtin causes downregulation of striatal signaling genes and particularly those normally induced by cAMP and retinoic acid. The present study expands the regional and temporal scope of this previous work by assessing whether similar changes occur in other brain regions affected in Huntington's disease and other polyglutamine diseases and by discerning whether gene expression changes precede the appearance of disease signs. Oligonucleotide microarrays were employed to survey the expression of approximately 11,000 mRNAs in the cerebral cortex, cerebellum and striatum of symptomatic R6/2 mice.