Project description:We performed ChIP-Seq analysis of SOX10, histone H3 lysine 27 acetylation (H3K27ac) and H3K27 trimethylation (H3K27me3) in melanocytes to profile the genomic binding sites of SOX10 and the chromatin landscape. In parallel, we generated Sox10 haploinsufficient cell lines using gene knockout approaches and conducted microarray gene expression analysis to identify functional gene targets of SOX10 transcriptional regulation in melanocytes. We demonstrate that SOX10 predominantly engages “open” chromatin, binds to melanocyte enhancer elements and plays a central role in transcriptional activation and repression of functionally distinct classes of genes. Furthermore, we identified cis-regulatory sequence motifs of putative co-regulatory transcription factors that define SOX10-activated and SOX10-repressed target genes. Our results uncover novel mechanisms and roles of SOX10 in global transcriptional regulation of diverse regulatory pathways in the melanocyte lineage. These results indicated that SOX10 plays a role in activation and repression of distinct classes of genes. Microarray gene expression analysis in Sox10 haploinsufficient immortal melanocyte cell lines derived from 3-day-old Sox10LacZ/+; Ink4a-Arf null mice. Syngeneic control cells were melan-Ink4a-Arf-1.
Project description:We performed ChIP-Seq analysis of SOX10, histone H3 lysine 27 acetylation (H3K27ac) and H3K27 trimethylation (H3K27me3) in melanocytes to profile the genomic binding sites of SOX10 and the chromatin landscape. In parallel, we generated Sox10 haploinsufficient cell lines using gene knockout approaches and conducted microarray gene expression analysis to identify functional gene targets of SOX10 transcriptional regulation in melanocytes. We demonstrate that SOX10 predominantly engages “open” chromatin, binds to melanocyte enhancer elements and plays a central role in transcriptional activation and repression of functionally distinct classes of genes. Furthermore, we identified cis-regulatory sequence motifs of putative co-regulatory transcription factors that define SOX10-activated and SOX10-repressed target genes. Our results uncover novel mechanisms and roles of SOX10 in global transcriptional regulation of diverse regulatory pathways in the melanocyte lineage. These results indicated that SOX10 plays a role in activation and repression of distinct classes of genes.
Project description:We performed ChIP-Seq analysis of SOX10, histone H3 lysine 27 acetylation (H3K27ac) and H3K27 trimethylation (H3K27me3) in melanocytes to profile the genomic binding sites of SOX10 and the chromatin landscape. In parallel, we generated Sox10 haploinsufficient cell lines using gene knockout approaches and conducted microarray gene expression analysis to identify functional gene targets of SOX10 transcriptional regulation in melanocytes. We demonstrate that SOX10 predominantly engages “open” chromatin, binds to melanocyte enhancer elements and plays a central role in transcriptional activation and repression of functionally distinct classes of genes. Furthermore, we identified cis-regulatory sequence motifs of putative co-regulatory transcription factors that define SOX10-activated and SOX10-repressed target genes. Our results uncover novel mechanisms and roles of SOX10 in global transcriptional regulation of diverse regulatory pathways in the melanocyte lineage. ChIP-seq profiling of SOX10, H3K27ac, and H3K27me3 in the mouse melanocyte cell line melan-Ink4a-Arf-1 (melan-a).
Project description:We performed ChIP-Seq analysis of SOX10, histone H3 lysine 27 acetylation (H3K27ac) and H3K27 trimethylation (H3K27me3) in melanocytes to profile the genomic binding sites of SOX10 and the chromatin landscape. In parallel, we generated Sox10 haploinsufficient cell lines using gene knockout approaches and conducted microarray gene expression analysis to identify functional gene targets of SOX10 transcriptional regulation in melanocytes. We demonstrate that SOX10 predominantly engages “open” chromatin, binds to melanocyte enhancer elements and plays a central role in transcriptional activation and repression of functionally distinct classes of genes. Furthermore, we identified cis-regulatory sequence motifs of putative co-regulatory transcription factors that define SOX10-activated and SOX10-repressed target genes. Our results uncover novel mechanisms and roles of SOX10 in global transcriptional regulation of diverse regulatory pathways in the melanocyte lineage.
Project description:Notch1 Activation Confers Transforming Properties to Primary Human Melanocytes and Promotes Human Melanoma Progression We used microarrays to detail the global programme of gene expression underlying cellularisation and identified distinct classes of up-regulated genes during this process.
Project description:Melanoma genomes are often characterized by large numbers of sunlight-induced mutations. However, epigenetic alterations, in the form of aberrant DNA methylation patterns, are also abundant. Using MIRA-seq, we have carried out a comprehensive characterization of the DNA methylome in a series of metastatic melanoma samples and catalogued the methylation changes relative to normal melanocytes, the presumed cells of origin for these tumors. Individual melanoma tumors contained up to several thousand hypermethylated regions. We discovered 179 tumor-specific methylation peaks that were present in all (27/27) melanomas and may lend themselves as effective disease biomarkers, and 3124 methylation peaks were present in >40% of the tumors. We specifically examined the relationship between presence of the Polycomb mark, H3K27me3 in melanocytes and tumor-specific DNA methylation in melanoma. We found that 150 of the approximately 1,200 tumor-associated methylation peaks near transcription start sites (TSS) were H3K27me3-marked in melanocytes. Notably, DNA methylation in melanoma was specific for distinct H3K27me3 peaks rather than for H3K27me3-enriched regions with broad genomic coverage. Yet, there were also numerous H3K27me3 peak-associated TSS regions that were completely resistant to DNA methylation in tumors. Furthermore, a rather large group of genes became methylated in melanoma but lacked H3K27me3 in melanocytes. There was no relationship between presence of BRAF V600 mutations and the number of methylation peaks in individual tumors. Gene expression analysis showed a strong signature of upregulated immune response genes in melanomas presumably as a result of lymphocyte infiltration. Genes down-regulated in tumors were enriched for melanocyte differentiation and pigmentation factors. Overall, there was limited correlation between tumor-associated DNA methylation changes and changes in gene expression although distinct melanocyte differentiation genes including KIT, PAX3 and SOX10 became methylated and downregulated in melanoma. Examination of H3K27me3 histone modification in human normal melanocytes.
Project description:Notch1 Activation Confers Transforming Properties to Primary Human Melanocytes and Promotes Human Melanoma Progression We used microarrays to detail the global programme of gene expression underlying cellularisation and identified distinct classes of up-regulated genes during this process. Human neonatal melanocytes and Notch transformed human neonatal melanocytes were selected for RNA extraction and hybridization on Illumina gene expression array chip. Expression intensities were calculated and normalized for each gene probed on the array for all hybridizations using illumina Beadstudio#3 software. Microarray analyses were subsequently performed in GeneSpring to aid in the identification of genes differentially-expressed between Notch-infected and control melanocytes that may be responsible for the phenotypic changes described in the NIC-infected cells.
Project description:The transcription factor SRY(sex related protein-Y)-box10 (SOX10) plays a key role in the development of melanocytes and peripheral glial cells from neural crest precursors. Recently, we and other groups found SOX10 to be involved in melanoma initiation, proliferation, invasion, and survival. However, specific mediators which impart the oncogenic role of SOX10 in melanoma remain widely unknown. To identify potential target genes of SOX10, we performed RNA sequencing to analyze genome-wide expression alterations after ectopic expression of SOX10. Among nine genes differentially regulated by SOX10, only peripheral myelin protein 2 (PMP2) was found upregulated in several other melanoma cell lines. PMP2 is one of the most abundant myelin proteins in glial cells and is necessary for the formation and maintenance of the myelin sheath. We detected PMP2 expression in a subset of human melanoma cell lines while it was absent in human melanocytes and fibroblasts. Direct binding of SOX10 to the PMP2 promoter was shown by chromatin immunoprecipitation and electrophoretic shift assay. In three-dimensional spheroid assays, we found that PMP2 overexpression increased melanoma cell invasion. In conclusion, we identified PMP2 as target gene of SOX10 and propose a novel role for PMP2 in melanoma cell invasion.