3′ sequencing from human Huntington's disease and control motor cortex and cerebellum.

Purpose: We applied polyA site sequencing (Passeq) to human Huntington's disease and control motor cortex and cerebellum to test if any genes change 3′UTR isoforms abundance. Methods: 3′ sequencing was performed on 6 motor cortices from grade 1 Huntington's patient brains, 4 motor cortices from grade 2 Huntington's patient brains, and 5 motor cortices from control brains. Cerebellum samples included 9 cerebella from grade 2-3 Huntington's patient brains, and 7 cerebella from control brains. To verify HTT isoforms in mice, sequencing was performed on 5 Q140 mouse striata and 3 wild-type mouse striata. Results: We report 11% of genes from Huntington's disease patient motor cortex exhibit a change in at least one of their 3′UTR isoforms, commensurate with the 11% of genes which show different total expression in HD motor cortex versus control. In contrast, gene isoform and expression changes are minimal (<5%) in Huntington's disease cerebellum versus controls. In the motor cortex, we show isoform and gene expression differs between between grade 1 and grade 2 brains. We identify a novel isoform of huntingtin mRNA which is conserved in wild-type and Huntington's model mice. Conclusions: This is the first study characterizing widespread alterations in 3′UTR isoform abundance in Huntington's disease. Alterations in isoform abundance may affect mRNA metabolism in Huntington's disease brains. Examination of 3′UTR isoform abundance in Huntington's disease and control motor cortex and cerebellum, and in Q140 and wild-type mouse striatum. 3′ sequencing was performed on 6 motor cortices from grade 1 Huntington's patient brains, 4 motor cortices from grade 2 Huntington's patient brains, and 5 motor cortices from control brains. Cerebellum samples included 9 cerebella from grade 2-3 Huntington's patient brains, and 7 cerebella from control brains. To verify HTT isoforms in mice, sequencing was performed on 5 Q140 mouse striata and 3 wild-type mouse striata.