Project description:Dynamic incorporation of histone H3 variants into chromatin is essential for acquisition of aggressive traits and metastatic colonization
Project description:Metastasis is the leading cause of cancer mortality. Chromatin remodeling is crucial for metastasis formation, laying the ground for the cellular reprogramming necessary to drive metastasis. However, little is known about the nature of this remodeling and its regulation. Here, we show that metastasis-inducing pathways regulate histone chaperones to reduce canonical histone incorporation into chromatin, triggering deposition of H3.3 variant at the promoters of poor-prognosis genes and metastasis-inducing transcription factors. This specific incorporation of H3.3 into chromatin is both necessary and sufficient for the induction of aggressive traits that allow for metastasis formation. Together, our data clearly show histone variant H3.3 as a major regulator of cell fate during tumorigenesis, and histone chaperones as valuable therapeutic targets for invasive carcinomas.
Project description:Dynamic incorporation of histone H3 variants into chromatin is essential for acquisition of aggressive traits and metastatic colonization [ATAC-seq]
Project description:Carcinomas can acquire metastatic potential by undergoing a cellular program referred to as epithelial-to-mesenchymal transition (EMT). During EMT, the genome undergoes major epigenetic changes required for the expression of genes that promote cell motility, invasiveness, and survival under stress. While recent data point to a crucial role of chromatin remodeling in this process, little is known about the nature of this remodeling and the signals that trigger it. Here we show that metastasis-inducing pathways regulate histone chaperones to reduce canonical histone incorporation into chromatin. This triggers deposition of H3.3 to the promoters of EMT-inducing transcription factors and poor prognosis genes, a phenomenon that is sufficient and necessary for the induction of EMT and metastasis. Together, we have discovered histone H3.3 variant as a major regulator of cell fate during tumorigenesis and histone chaperones as valuable therapeutic targets for metastatic disease.
Project description:Carcinomas can acquire metastatic potential by undergoing a cellular program referred to as epithelial-to-mesenchymal transition (EMT). During EMT, the genome undergoes major epigenetic changes required for the expression of genes that promote cell motility, invasiveness, and survival under stress. While recent data point to a crucial role of chromatin remodeling in this process, little is known about the nature of this remodeling and the signals that trigger it. Here we show that metastasis-inducing pathways regulate histone chaperones to reduce canonical histone incorporation into chromatin. This triggers deposition of H3.3 to the promoters of EMT-inducing transcription factors and poor prognosis genes, a phenomenon that is sufficient and necessary for the induction of EMT and metastasis. Together, we have discovered histone H3.3 variant as a major regulator of cell fate during tumorigenesis and histone chaperones as valuable therapeutic targets for metastatic disease.
Project description:Metastasis is the leading cause of cancer mortality. Chromatin remodeling provides the foundation for the cellular reprogramming necessary to drive metastasis. However, little is known about the nature of this remodeling and its regulation. Here, we show that metastasis-inducing pathways regulate histone chaperones to reduce canonical histone incorporation into chromatin, triggering deposition of H3.3 variant at the promoters of poor-prognosis genes and metastasis-inducing transcription factors. This specific incorporation of H3.3 into chromatin is both necessary and sufficient for the induction of aggressive traits that allow for metastasis formation. Together, our data clearly show incorporation of histone variant H3.3 into chromatin as a major regulator of cell fate during tumorigenesis, and histone chaperones as valuable therapeutic targets for invasive carcinomas.
Project description:Reductive dimethylation based binary quantification of histone proteins from control (EGFP) and ERK2 (D319N) overexpressing MCF10A cells.
Project description:Nucleosomal incorporation of specialized histone variants is an important mechanism to generate different functional chromatin states. Here we report the identification and characterization of two novel primate-specific histone H3 variants, H3.X and H3.Y. Their mRNAs are found in certain human cell lines, in addition to several normal and malignant human tissues. In keeping with their primate-specificity, H3.X and H3.Y are detected in different brain regions. Transgenic H3.X and H3.Y proteins are stably incorporated into chromatin in a similar fashion to the known H3 variants. Importantly, we demonstrate biochemically and by mass spectrometry that endogenous posttranslationally modified H3.Y protein exists in vivo, and that stress-stimuli, such as starvation and cellular density, increase the abundance of H3.Y-expressing cells. Global transcriptome analysis revealed that knock-down of H3.Y affects cell growth and leads to changes in the expression of many genes involved in cell cycle control. Thus, H3.Y is a novel histone variant involved in the regulation of cellular responses to outside stimuli. Total RNA samples from human U2OS cells. Transcript levels after luciferase, H3.X and/or H3.Y RNAi was analyzed.
Project description:Nucleosomal incorporation of specialized histone variants is an important mechanism to generate different functional chromatin states. Here we report the identification and characterization of two novel primate-specific histone H3 variants, H3.X and H3.Y. Their mRNAs are found in certain human cell lines, in addition to several normal and malignant human tissues. In keeping with their primate-specificity, H3.X and H3.Y are detected in different brain regions. Transgenic H3.X and H3.Y proteins are stably incorporated into chromatin in a similar fashion to the known H3 variants. Importantly, we demonstrate biochemically and by mass spectrometry that endogenous posttranslationally modified H3.Y protein exists in vivo, and that stress-stimuli, such as starvation and cellular density, increase the abundance of H3.Y-expressing cells. Global transcriptome analysis revealed that knock-down of H3.Y affects cell growth and leads to changes in the expression of many genes involved in cell cycle control. Thus, H3.Y is a novel histone variant involved in the regulation of cellular responses to outside stimuli.