The chromatin remodeling ATPases SNF2H and SNF2L position nucleosomes adjacent to CTCF and other transcription factors.
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ABSTRACT:
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| ERR1299110_1.fastq.gz | Fastqsanger.gz | |||
| ERR1299110_2.fastq.gz | Fastqsanger.gz | |||
| ERR1299120_1.fastq.gz | Fastqsanger.gz | |||
| ERR1299120_2.fastq.gz | Fastqsanger.gz | |||
| ERR1299130_1.fastq.gz | Fastqsanger.gz |
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Project description:Snf2l and the closely related protein, Snf2h, play a critical role in embryonic and post-natal brain development. Murine models lacking functional Snf2h or Snf2l point to complementary activities of these remodelers; Snf2h cKO mice present with a significantly reduced cerebellum, while Snf2l Ex6DEL cerebella are larger than their wild-type counterparts. Granule neuron progenitors (GNPs) isolated from Ex6DEL cerebella display delayed cell cycle exit and hindered terminal differentiation compared to wild-type littermates. Moreover, loss of Snf2l activity results in widespread transcriptome shifts which underlie the Ex6DEL GNP differentiation phenotype. In particular, key transcription factors (TFs) are differentially expressed without Snf2l remodelling activity. We confirm that ERK pathway activation is misregulated in Ex6DEL GNPs, possibly in response to elevated fibroblast growth factor 8 (Fgf8) expression in these cultures. We find that Snf2l activity maintains the chromatin landscape throughout GNP differentiation, as Ex6DEL cultures have a global increase in chromatin accessibility. We suggest that Snf2l-mediated chromatin condensation is responsible for proper regulation of gene expression programs in GNP differentiation.
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Project description:Snf2l and the closely related protein, Snf2h, play a critical role in embryonic and post-natal brain development. Murine models lacking functional Snf2h or Snf2l point to complementary activities of these remodelers; Snf2h cKO mice present with a significantly reduced cerebellum, while Snf2l Ex6DEL cerebella are larger than their wild-type counterparts. Granule neuron progenitors (GNPs) isolated from Ex6DEL cerebella display delayed cell cycle exit and hindered terminal differentiation compared to wild-type littermates. Moreover, loss of Snf2l activity results in widespread transcriptome shifts which underlie the Ex6DEL GNP differentiation phenotype. In particular, key transcription factors (TFs) are differentially expressed without Snf2l remodelling activity. We confirm that ERK pathway activation is misregulated in Ex6DEL GNPs, possibly in response to elevated fibroblast growth factor 8 (Fgf8) expression in these cultures. We find that Snf2l activity maintains the chromatin landscape throughout GNP differentiation, as Ex6DEL cultures have a global increase in chromatin accessibility. We suggest that Snf2l-mediated chromatin condensation is responsible for proper regulation of gene expression programs in GNP differentiation.
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Project description:ISWI is an evolutionary conserved ATPase that catalyzes nucleosome remodeling in several different complexes. Two mammalian ISWI orthologs, SNF2H and SNF2L, have specialized functions despite their high similarity. Due to the lack of reagents the functions of SN2L in human cells had not been established. Newly established specific monoclonal antibodies and selective RNA interference protocols now enabled a comprehensive characterization of loss-of-function phenotypes in human cells. Contrasting earlier results obtained in the mouse model, we found SNF2L broadly expressed in primary human tissues. Depletion of SNF2L in HeLa cells led to enhanced proliferation, morphological alterations and increased migration. These phenomena were explained by transcriptome profiling, which identified SNF2L as a modulator of the Wnt signaling network. The cumulative effects of SNF2L depletion on gene expression portray the cell in a state of activated Wnt signaling characterized by increased proliferation and chemotactic locomotion. High levels of SNF2L expression in normal melanocytes contrast to undetectable expression in malignant melanoma. In summary, our data document an anti-correlation between SNF2L expression and several features characteristic of malignant cells.
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