Project description:Huntington's disease (HD) features a unique disease-initiating mechanism hypothesized to entail an impact of the CAG repeat encoded polyglutamine region on the full-length huntingtin protein, with dominant effects that are continuous with CAG size, in a simple gain of function. To evaluate these predictions, we generated a series of heterozygous Hdh CAG knock-in mouse embryonic stem (ES) cell lines, with 18, 48, 89, 109 CAGs, and found that a continuous analytic strategy efficiently identified, from genome-wide datasets, 73 genes and 172 pathways whose expression varied continuously with CAG length. The CAG-correlated genes were distinct from the set of 754 genes that distinguished huntingtin null ES cells from wild-type controls, and CAG-correlated pathways did not display a one-to-one correspondence with the 238 pathways altered in huntingtin null ES cells. Rather, the genes that varied with CAG size were either members of the same pathways as altered genes in huntingtin null cells or were members of unique pathways related to these pathways. These findings falsified a gain of function/loss of function proposal but were consistent with the simple gain of novel function mechanism hypothesis. The dominant CAG correlated gene expression changes conformed to the genetic features of the HD initiating mechanism and were system-wide and inter-related with pathways perturbed by lack of full-length huntingtin function, urging system-wide approaches for the discovery and validation of potential modulating factors, in the search for effective HD therapeutics. Undifferentiated mouse embryonic stem cells without Hdh or with knock-in alleles with different Hdh CAG repeat sizes were profiled by Affymetrix MG 430 2.0 arrays.
Project description:Huntington's disease (HD) features a unique disease-initiating mechanism hypothesized to entail an impact of the CAG repeat encoded polyglutamine region on the full-length huntingtin protein, with dominant effects that are continuous with CAG size, in a simple gain of function. To evaluate these predictions, we generated a series of heterozygous Hdh CAG knock-in mouse embryonic stem (ES) cell lines, with 18, 48, 89, 109 CAGs, and found that a continuous analytic strategy efficiently identified, from genome-wide datasets, 73 genes and 172 pathways whose expression varied continuously with CAG length. The CAG-correlated genes were distinct from the set of 754 genes that distinguished huntingtin null ES cells from wild-type controls, and CAG-correlated pathways did not display a one-to-one correspondence with the 238 pathways altered in huntingtin null ES cells. Rather, the genes that varied with CAG size were either members of the same pathways as altered genes in huntingtin null cells or were members of unique pathways related to these pathways. These findings falsified a gain of function/loss of function proposal but were consistent with the simple gain of novel function mechanism hypothesis. The dominant CAG correlated gene expression changes conformed to the genetic features of the HD initiating mechanism and were system-wide and inter-related with pathways perturbed by lack of full-length huntingtin function, urging system-wide approaches for the discovery and validation of potential modulating factors, in the search for effective HD therapeutics.
Project description:Expression data from wild type or Gdap1-null Mouse Embryonic Fibroblasts before and 4 days after transduction with the reprogramming factors Oct4, Sox2, Klf4 and cMyc We used microarrays to detail the global programme of gene expression underlying cell reprogramming Total RNA from wild type or Gdap1-null Mouse Embryonic Fibroblasts was extracted before or at day 4 of reprogramming and hybridised on affymetrix microarrays
Project description:Myogenic differentiation relies on Pax7 function. We used mouse embryonic fibroblasts lacking functional Pax7 to follow its role in terminally differentiated cells. Microarray analysis allowed us to compare transcriptomes of mouse embryonic fibroblasts of two genotypes, i.e. Pax7+/+ and Pax7-/-.
Project description:We have here followed the transcriptional effect of stimulation with the phorbol ester PMA in mouse fibroblasts from HP1gamma null mice recomplemented with either wild-type HP1gamma or an HP1g with an S83A mutation Spontaneously immortalized mouse embryonic fibroblasts from HP1gamma null mice were used to stably integrate either an empty expression vector, or expression vectors for either WT or S83A mutant HP1gamma. These cells were then stimulated with PMA for 0 or 60 min. and used for transcriptome analysis by Next Generation sequencing.
