E-GEOD-5786 - Transcription profiling of striata from PGC-1a knockout mice and litter mate controls to understand the roles of PGC-1a.
Submitted on 7 September 2006, released on 13 November 2007, last updated on 27 March 2012
Huntington's Disease (HD) is an inherited neurodegenerative disease caused by a glutamine repeat expansion in huntingtin protein. Transcriptional deregulation and altered energy metabolism have been implicated in HD pathogenesis. We report here that mutant huntingtin causes disruption of mitochondrial function by inhibiting expression of PGC-1a, a transcriptional coactivator that regulates several metabolic processes including mitochondrial biogenesis and respiration. Mutant huntingtin represses PGC-1a gene transcription by associating with the promoter and interfering with the CREB/TAF4-dependent transcriptional pathway critical for the regulation of PGC-1a gene expression. Crossbreeding of PGC-1a knockout mice with HD knock-in mice leads to increased neurodegeneration of striatal neurons and motor abnormalities in the HD mice. Importantly, expression of PGC-1a partially reverses the toxic effects of mutant huntingtin in cultured striatal neurons. Moreover, lentiviral-mediated delivery of PGC-1a in the striatum provides neuroprotection in the transgenic HD mice. These studies suggest a key role for PGC-1a in the control of energy metabolism in the early stages of HD pathogenesis. Experiment Overall Design: Total RNA was extracted from striata of 3 pgc1 KO mice and 3 littermate controls using the RNeasy Mini Kit (Qiagen) according to manufacturer's protocol. Samples were analyzed using RNA 6000 Nano LabChip kit on a 2100 Bioanalyzer (Agilent Technologies) to ensure integrity of RNA.
transcription profiling by array, co-expression, individual genetic characteristics
Transcriptional repression of PGC-1alpha by mutant huntingtin leads to mitochondrial dysfunction and neurodegeneration. Libin Cui, Hyunkyung Jeong, Fran Borovecki, Christopher N Parkhurst, Naoko Tanese, Dimitri Krainc. Cell 127(1):59-69 (2006)