Project description:Aberrant splice variants are involved in the initiation and/or progression of glial brain tumors. We therefore set out to identify splice variants that are differentially expressed between histological subgroups of gliomas. Splice variants were identified using a novel platform that profiles the expression of virtually all known and predicted exons present in the human genome. Exon-level expression profiling was performed on 26 glioblastomas, 22 oligodendrogliomas and 6 control brain samples. Our results demonstrate that Human Exon arrays can identify subgroups of gliomas based on their histological appearance and genetic aberrations. We next used our expression data to identify differentially expressed splice variants. In two independent approaches, we identified 49 and up to 459 exons that are differentially spliced between glioblastomas and oligodendrogliomas a subset of which (47% and 33%) were confirmed by RT-PCR. In addition, exon-level expression profiling also identified >700 novel exons. Expression of ~67% of these candidate novel exons was confirmed by RT-PCR. Our results indicate that exon-level expression profiling can be used to molecularly classify brain tumor subgroups, can identify differentially regulated splice variants and can identify novel exons. The splice variants identified by exon-level expression profiling may help to detect the genetic changes that cause or maintain gliomas and may serve as novel treatment targets. Keywords: cell type comparison 6 adult non diseased brain, 26 glioblastomas, 21 oligodendrogliomas
Project description:Aberrant splice variants are involved in the initiation and/or progression of glial brain tumors. We therefore set out to identify splice variants that are differentially expressed between histological subgroups of gliomas. Splice variants were identified using a novel platform that profiles the expression of virtually all known and predicted exons present in the human genome. Exon-level expression profiling was performed on 26 glioblastomas, 22 oligodendrogliomas and 6 control brain samples. Our results demonstrate that Human Exon arrays can identify subgroups of gliomas based on their histological appearance and genetic aberrations. We next used our expression data to identify differentially expressed splice variants. In two independent approaches, we identified 49 and up to 459 exons that are differentially spliced between glioblastomas and oligodendrogliomas a subset of which (47% and 33%) were confirmed by RT-PCR. In addition, exon-level expression profiling also identified >700 novel exons. Expression of ~67% of these candidate novel exons was confirmed by RT-PCR. Our results indicate that exon-level expression profiling can be used to molecularly classify brain tumor subgroups, can identify differentially regulated splice variants and can identify novel exons. The splice variants identified by exon-level expression profiling may help to detect the genetic changes that cause or maintain gliomas and may serve as novel treatment targets. Keywords: cell type comparison
Project description:The X-chromosomal dystonia parkinsonism syndrome (XDP) is associated with sequence changes within the TAF1/DYT3 multiple transcript system. While most sequence changes are intronic, one, DSC3, is located within an exon (d4). Transcribed exon d4 occurs as part of multiple splice variants. These variants include exons d3 and d4 spliced to exons of TAF1, and an independent transcript composed of exons d2-d4. Location of DSC3 in an exon (d4) and utilization of this exon in multiple splice variants suggests an important role of DSC3 in the pathogenesis of XDP. To test this hypothesis we transfected neuroblastoma cells with four expression constructs, including exons d2-d4 (d2-d4/wild-type (wt) and d2-d4/DSC3) and d3-d4 (d3-d4/wt and d3-d4/DSC3). Expression profiling revealed a dramatic effect of DSC3 on overall gene expression. 362 genes differ between cells containing d2-d4/wt and d2-d4/DSC3. Annotation clustering revealed high enrichment of genes related to dopamine metabolism, vesicular transport, synapse function, Ca++ metabolism, and oxidative stress. 211 genes were differentially expressed in d3-d4/wt vs. d3-d4/DSC3. Annotation clustering highlighted genes in signal transduction and cell-cell interaction. The data shows an important role of physiologically occurring transcript d2-d4 in normal brain function. Interference with this role by DSC3 is a likely pathological mechanism in XDP. Disturbance of dopamine function and of Ca++ metabolism can explain abnormal movement; loss of protection against reactive oxygen species may account for the neurodegenerative changes in XDP. Although d3-d4 also affect genes potentially related to neurodegenerative processes their physiologic role as splice variants of TAF1 awaits further exploration. We transfected neuroblastoma cells with four expression constructs, including exons d2-d4 (d2-d4/wild-type (wt) and d2-d4/DSC3) and d3-d4 (d3-d4/wt and d3-d4/DSC3).
Project description:The X-chromosomal dystonia parkinsonism syndrome (XDP) is associated with sequence changes within the TAF1/DYT3 multiple transcript system. While most sequence changes are intronic, one, DSC3, is located within an exon (d4). Transcribed exon d4 occurs as part of multiple splice variants. These variants include exons d3 and d4 spliced to exons of TAF1, and an independent transcript composed of exons d2-d4. Location of DSC3 in an exon (d4) and utilization of this exon in multiple splice variants suggests an important role of DSC3 in the pathogenesis of XDP. To test this hypothesis we transfected neuroblastoma cells with four expression constructs, including exons d2-d4 (d2-d4/wild-type (wt) and d2-d4/DSC3) and d3-d4 (d3-d4/wt and d3-d4/DSC3). Expression profiling revealed a dramatic effect of DSC3 on overall gene expression. 362 genes differ between cells containing d2-d4/wt and d2-d4/DSC3. Annotation clustering revealed high enrichment of genes related to dopamine metabolism, vesicular transport, synapse function, Ca++ metabolism, and oxidative stress. 211 genes were differentially expressed in d3-d4/wt vs. d3-d4/DSC3. Annotation clustering highlighted genes in signal transduction and cell-cell interaction. The data shows an important role of physiologically occurring transcript d2-d4 in normal brain function. Interference with this role by DSC3 is a likely pathological mechanism in XDP. Disturbance of dopamine function and of Ca++ metabolism can explain abnormal movement; loss of protection against reactive oxygen species may account for the neurodegenerative changes in XDP. Although d3-d4 also affect genes potentially related to neurodegenerative processes their physiologic role as splice variants of TAF1 awaits further exploration.
Project description:The latest version of microarrays released by Affymetrix, the GeneChip Gene 1.0 ST Arrays (gene arrays), are designed in a similar fashion as exon arrays, which enables to identify differentially expressed exons, rather than only the expression level of whole transcripts. Here, we propose an extension, Gene Array Analyzer (GAA), to our previously published Exon Array Analyzer (EAA). GAA enables to analyse gene arrays on exon level and therefore supports to identify alternative splicing with gene arrays. To show the applicability of GAA, we used gene arrays to profile alternative splice events during the development of the heart. Further re-analysis of published gene arrays could show, that some of these splice events reoccur under pathological conditions. The web interface of GAA is user friendly, functional without set up and freely available at http://GAA.mpi-bn.mpg.de.
Project description:The latest version of microarrays released by Affymetrix, the GeneChip Gene 1.0 ST Arrays (gene arrays), are designed in a similar fashion as exon arrays, which enables to identify differentially expressed exons, rather than only the expression level of whole transcripts. Here, we propose an extension, Gene Array Analyzer (GAA), to our previously published Exon Array Analyzer (EAA). GAA enables to analyse gene arrays on exon level and therefore supports to identify alternative splicing with gene arrays. To show the applicability of GAA, we used gene arrays to profile alternative splice events during the development of the heart. Further re-analysis of published gene arrays could show, that some of these splice events reoccur under pathological conditions. The web interface of GAA is user friendly, functional without set up and freely available at http://GAA.mpi-bn.mpg.de.
Project description:To clarify the functional properties of FUS, we established the differentially expressed alternative exons in FUS-silenced primary motor neurons by using exon-sensitive microarray technology. To clarify the functional properties of FUS, we established the differentially expressed alternative exons in FUS-silenced primary glial cells by using exon-sensitive microarray technology. To clarify the functional properties of FUS, we established the differentially expressed alternative exons in FUS-silenced primary cerebellar neurons by using exon-sensitive microarray technology.
Project description:Alternative splicing (AS) generates extensive transcriptomic and proteomic complexity. However, the functions of species- and lineage-specific splice variants are largely unknown. Here, we show that mammalian-specific skipping of exon 9 of PTBP1 alters its splicing regulatory activities and affects the inclusion levels of numerous exons. During neurogenesis, skipping of exon 9 reduces PTBP1 repressive activity so as to facilitate activation of a brain-specific AS program. Engineered skipping of the orthologous exon in chicken cells induces a large number of mammalian-like AS changes in PTBP1 target exons. These results thus reveal that a single exon skipping event in an RNA binding regulator directs numerous AS changes between species. The results further suggest that these changes contributed to evolutionary differences in the formation of vertebrate nervous systems.
Project description:The latest version of microarrays released by Affymetrix, the GeneChip Gene 1.0 ST Arrays (gene arrays), are designed in a similar fashion as exon arrays, which enables to identify differentially expressed exons, rather than only the expression level of whole transcripts. Here, we propose an extension, Gene Array Analyzer (GAA), to our previously published Exon Array Analyzer (EAA). GAA enables to analyse gene arrays on exon level and therefore supports to identify alternative splicing with gene arrays. To show the applicability of GAA, we used gene arrays to profile alternative splice events during the development of the heart. Further re-analysis of published gene arrays could show, that some of these splice events reoccur under pathological conditions. The web interface of GAA is user friendly, functional without set up and freely available at http://GAA.mpi-bn.mpg.de. Alternative splicing and gene expression analysis during development of the heart and cardiomyoyte differentiation.
Project description:The latest version of microarrays released by Affymetrix, the GeneChip Gene 1.0 ST Arrays (gene arrays), are designed in a similar fashion as exon arrays, which enables to identify differentially expressed exons, rather than only the expression level of whole transcripts. Here, we propose an extension, Gene Array Analyzer (GAA), to our previously published Exon Array Analyzer (EAA). GAA enables to analyse gene arrays on exon level and therefore supports to identify alternative splicing with gene arrays. To show the applicability of GAA, we used gene arrays to profile alternative splice events during the development of the heart. Further re-analysis of published gene arrays could show, that some of these splice events reoccur under pathological conditions. The web interface of GAA is user friendly, functional without set up and freely available at http://GAA.mpi-bn.mpg.de. Alternative splicing and gene expression analysis during development of the heart and cardiomyoyte differentiation.