Project description:Hamey2017 - Blood stem cell regulatory
network
This model is described in the article:
Reconstructing blood stem
cell regulatory network models from single-cell molecular
profiles
Fiona K. Hamey, Sonia Nestorowa,
Sarah J. Kinston, David G. Kent, Nicola K. Wilson, and Berthold
Göttgens
Proceedings of the National Academy of
Sciences of the United States of America
Abstract:
Adult blood contains a mixture of mature cell types, each
with specialized functions. Single hematopoietic stem cells
(HSCs) have been functionally shown to generate all mature cell
types for the lifetime of the organism. Differentiation of HSCs
toward alternative lineages must be balanced at the population
level by the fate decisions made by individual cells.
Transcription factors play a key role in regulating these
decisions and operate within organized regulatory programs that
can be modeled as transcriptional regulatory networks. As
dysregulation of single HSC fate decisions is linked to fatal
malignancies such as leukemia, it is important to understand
how these decisions are controlled on a cell-by-cell basis.
Here we developed and applied a network inference method,
exploiting the ability to infer dynamic information from
single-cell snapshot expression data based on expression
profiles of 48 genes in 2,167 blood stem and progenitor cells.
This approach allowed us to infer transcriptional regulatory
network models that recapitulated differentiation of HSCs into
progenitor cell types, focusing on trajectories toward
megakaryocyte–erythrocyte progenitors and lymphoid-primed
multipotent progenitors. By comparing these two models, we
identified and subsequently experimentally validated a
difference in the regulation of nuclear factor, erythroid 2
(Nfe2) and core-binding factor, runt domain, alpha subunit 2,
translocated to, 3 homolog (Cbfa2t3h) by the transcription
factor Gata2. Our approach confirms known aspects of
hematopoiesis, provides hypotheses about regulation of HSC
differentiation, and is widely applicable to other hierarchical
biological systems to uncover regulatory relationships.
This model is hosted on
BioModels Database
and identified by:
MODEL1610060000.
To cite BioModels Database, please use:
BioModels Database:
An enhanced, curated and annotated resource for published
quantitative kinetic models.
To the extent possible under law, all copyright and related or
neighbouring rights to this encoded model have been dedicated to
the public domain worldwide. Please refer to
CC0
Public Domain Dedication for more information.
Project description:Hamey2017 - Blood stem cell regulatory
network (LMPP network)
This model is described in the article:
Reconstructing blood stem
cell regulatory network models from single-cell molecular
profiles
Fiona K. Hamey, Sonia Nestorowa,
Sarah J. Kinston, David G. Kent, Nicola K. Wilson, and Berthold
Göttgens
Proceedings of the National Academy of
Sciences of the United States of America
Abstract:
Adult blood contains a mixture of mature cell types, each
with specialized functions. Single hematopoietic stem cells
(HSCs) have been functionally shown to generate all mature cell
types for the lifetime of the organism. Differentiation of HSCs
toward alternative lineages must be balanced at the population
level by the fate decisions made by individual cells.
Transcription factors play a key role in regulating these
decisions and operate within organized regulatory programs that
can be modeled as transcriptional regulatory networks. As
dysregulation of single HSC fate decisions is linked to fatal
malignancies such as leukemia, it is important to understand
how these decisions are controlled on a cell-by-cell basis.
Here we developed and applied a network inference method,
exploiting the ability to infer dynamic information from
single-cell snapshot expression data based on expression
profiles of 48 genes in 2,167 blood stem and progenitor cells.
This approach allowed us to infer transcriptional regulatory
network models that recapitulated differentiation of HSCs into
progenitor cell types, focusing on trajectories toward
megakaryocyte–erythrocyte progenitors and lymphoid-primed
multipotent progenitors. By comparing these two models, we
identified and subsequently experimentally validated a
difference in the regulation of nuclear factor, erythroid 2
(Nfe2) and core-binding factor, runt domain, alpha subunit 2,
translocated to, 3 homolog (Cbfa2t3h) by the transcription
factor Gata2. Our approach confirms known aspects of
hematopoiesis, provides hypotheses about regulation of HSC
differentiation, and is widely applicable to other hierarchical
biological systems to uncover regulatory relationships.
This model is hosted on
BioModels Database
and identified by:
MODEL1610060001.
To cite BioModels Database, please use:
BioModels Database:
An enhanced, curated and annotated resource for published
quantitative kinetic models.
To the extent possible under law, all copyright and related or
neighbouring rights to this encoded model have been dedicated to
the public domain worldwide. Please refer to
CC0
Public Domain Dedication for more information.
Project description:<p>Non-coding elements in our genomes that play critical roles in complex disease are frequently marked by highly unstable RNA species. Sequencing nascent RNAs attached to an actively transcribing RNA polymerase complex can identify unstable RNAs, including those templated from gene-distal enhancers (eRNAs). However, nascent RNA sequencing techniques remain challenging to apply in some cell lines and especially to intact tissues, limiting broad applications in fields such as cancer genomics and personalized medicine. Here we report the development of chromatin run-on and sequencing (ChRO-seq), a novel run-on technology that maps the location of RNA polymerase using virtually any frozen tissue sample, including samples with degraded RNA that are intractable to conventional RNA-seq. We used ChRO-seq to develop the first maps of nascent transcription in 23 human glioblastoma (GBM) brain tumors and patient derived xenografts. Remarkably, >90,000 distal enhancers discovered using the signature of eRNA biogenesis within primary GBMs closely resemble those found in the normal human brain, and diverge substantially from GBM cell models. Despite extensive overall similarity, 12% of enhancers in each GBM distinguish normal and malignant brain tissue. These enhancers drive regulatory programs similar to the developing nervous system and are enriched for transcription factor binding sites that specify a stem-like cell fate. These results demonstrate that GBMs largely retain the enhancer landscape associated with their tissue of origin, but selectively adopt regulatory programs that are responsible for driving stem-like cell properties. We also identified enhancers and their associated transcription factors that regulate genes characteristic of each known GBM subtype, and discovered a core group of transcription factors that control the expression of genes associated with clinical outcomes. This study uncovers new insights into the molecular etiology of GBM and introduces ChRO-seq which can now be used to map regulatory programs contributing to a variety of complex diseases.</p>
Project description:The H2A variant H2AZ is essential for embryonic development and for proper execution of developmental gene expression programs in embryonic stem cells (ESCs). Divergent regions in H2AZ are likely key for its functional specialization, but we know little about how these differences contribute to chromatin regulation. Here, we show that the extended acidic patch, specifically the three divergent residues in the C-terminal docking domain, is necessary for lineage commitment during ESC differentiation and proper execution of gene expression programs during ESC differentiation. Surprisingly, disruption of the acidic patch domain has a distinct consequence on cellular specification compared to H2AZ depletion. This is consistent with differences in gene expression profiles of H2AZ M-bM-^@M-^Sdepleted and acidic patch (AP) mutant ESCs during early lineage commitment. Interestingly, the distinct consequence of AP mutant expression on gene regulation is coincidence with an altered destabilized chromatin state and high chromatin mobility dependent on active transcription. Collectively, our data shows that the divergent residues within the acidic patch domain are key structural determinants of H2AZ function and links chromatin structure and dynamics with gene regulation and cell fate specification. H2AZ extended acidic patch was mutated, or H2AZ was KD in mouse embryonic stem cells and RNA-Seq analysis was performed on the resulting cultures. Characterization of H2AZ-WT and -AP3-mutant binding specificities were performed by ChIP-Seq.
Project description:The H2A variant H2AZ is essential for embryonic development and for proper execution of developmental gene expression programs in embryonic stem cells (ESCs). Divergent regions in H2AZ are likely key for its functional specialization, but we know little about how these differences contribute to chromatin regulation. Here, we show that the extended acidic patch, specifically the three divergent residues in the C-terminal docking domain, is necessary for lineage commitment during ESC differentiation and proper execution of gene expression programs during ESC differentiation. Surprisingly, disruption of the acidic patch domain has a distinct consequence on cellular specification compared to H2AZ depletion. This is consistent with differences in gene expression profiles of H2AZ M-bM-^@M-^Sdepleted and acidic patch (AP) mutant ESCs during early lineage commitment. Interestingly, the distinct consequence of AP mutant expression on gene regulation is coincidence with an altered destabilized chromatin state and high chromatin mobility dependent on active transcription. Collectively, our data shows that the divergent residues within the acidic patch domain are key structural determinants of H2AZ function and links chromatin structure and dynamics with gene regulation and cell fate specification. H2AZ extended acidic patch was mutated, or H2AZ was KD in mouse embryonic stem cells and RNA-Seq analysis was performed on the resulting cultures. Characterization of H2AZ-WT and -AP3-mutant binding specificities were performed by ChIP-Seq.
Project description:This SuperSeries is composed of the following subset Series: GSE30537: Dissecting the retinoid-induced differentiation of F9 embryonal stem cells by integrative genomics [mRNA profiling] GSE30538: Dissecting the retinoid-induced differentiation of F9 embryonal stem cells by integrative genomics [ChIP-seq] Refer to individual Series