Single-cell epigenomics maps the continuous regulatory landscape of human hematopoietic differentiation

AbstractNormal human hematopoiesis involves cellular differentiation of multipotent cells into progressively more lineage-restricted states. While epigenomic landscapes of this process have been explored in immunophenotypically-defined populations, the single-cell regulatory variation that defines hematopoietic differentiation has been hidden by ensemble averaging. We generated single-cell chromatin accessibility landscapes across 8 populations of immunophenotypically-defined human hematopoietic cell types. Using bulk chromatin accessibility profiles to scaffold our single-cell data analysis, we constructed an epigenomic landscape of human hematopoiesis and characterized epigenomic heterogeneity within phenotypically sorted populations to find epigenomic lineage-bias toward different developmental branches in multipotent stem cell states. We identify and isolate sub-populations within classically-defined granulocyte-macrophage progenitors (GMPs) and use ATAC-seq and RNA-seq to confirm that GMPs are epigenomically and transcriptomically heterogeneous. Furthermore, we identified transcription factors andcis-regulatory elements linked to changes in chromatin accessibility within cellular populations and across a continuous myeloid developmental trajectory, and observe relatively simple TF motif dynamics give rise to a broad diversity of accessibility dynamics at cis-regulatory elements. Overall, this work provides a template for exploration of complex regulatory dynamics in primary human tissues at the ultimate level of granular specificity – the single cell.One Sentence SummarySingle cell chromatin accessibility reveals a high-resolution, continuous landscape of regulatory variation in human hematopoiesis.

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Functional Inference of Gene Regulation using Single-Cell Multi-Omics

10.1101/2021.07.28.453784 ◽

2021 ◽

Author(s):

Vinay K Kartha ◽

Fabiana M Duarte ◽

Yan Hu ◽

Sai Ma ◽

Jennifer G Chew ◽

...

Keyword(s):

Gene Expression ◽

Single Cell ◽

Regulatory Networks ◽

Immunological Response ◽

Cell Types ◽

Regulatory Elements ◽

Chromatin Accessibility ◽

Human Blood Cells ◽

Functional Inference ◽

Omic Data

Cells require coordinated control over gene expression when responding to environmental stimuli. Here, we apply scATAC-seq and scRNA-seq in resting and stimulated human blood cells. Collectively, we generate ~91,000 single-cell profiles, allowing us to probe the cis -regulatory landscape of immunological response across cell types, stimuli and time. Advancing tools to integrate multi-omic data, we develop FigR - a framework to computationally pair scATAC-seq with scRNA-seq cells, connect distal cis -regulatory elements to genes, and infer gene regulatory networks (GRNs) to identify candidate TF regulators. Utilizing these paired multi-omic data, we define Domains of Regulatory Chromatin (DORCs) of immune stimulation and find that cells alter chromatin accessibility prior to production of gene expression at time scales of minutes. Further, the construction of the stimulation GRN elucidates TF activity at disease-associated DORCs. Overall, FigR enables the elucidation of regulatory interactions across single-cell data, providing new opportunities to understand the function of cells within tissues.

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Single-cell regulatory landscape and disease vulnerability map of adult Macaque cortex

10.1101/2020.05.14.087601 ◽

2020 ◽

Author(s):

Ying Lei ◽

Mengnan Cheng ◽

Zihao Li ◽

Zhenkun Zhuang ◽

Liang Wu ◽

...

Keyword(s):

Gene Expression ◽

Single Cell ◽

Primary Motor Cortex ◽

Neurological Diseases ◽

Single Cells ◽

Cell Types ◽

Regulatory Elements ◽

Chromatin Accessibility ◽

Nucleotide Polymorphisms ◽

Cell Type

Non-human primates (NHP) provide a unique opportunity to study human neurological diseases, yet detailed characterization of the cell types and transcriptional regulatory features in the NHP brain is lacking. We applied a combinatorial indexing assay, sci-ATAC-seq, as well as single-nuclei RNA-seq, to profile chromatin accessibility in 43,793 single cells and transcriptomics in 11,477 cells, respectively, from prefrontal cortex, primary motor cortex and the primary visual cortex of adult cynomolgus monkey Macaca fascularis. Integrative analysis of these two datasets, resolved regulatory elements and transcription factors that specify cell type distinctions, and discovered area-specific diversity in chromatin accessibility and gene expression within excitatory neurons. We also constructed the dynamic landscape of chromatin accessibility and gene expression of oligodendrocyte maturation to characterize adult remyelination. Furthermore, we identified cell type-specific enrichment of differentially spliced gene isoforms and disease-associated single nucleotide polymorphisms. Our datasets permit integrative exploration of complex regulatory dynamics in macaque brain tissue at single-cell resolution.

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Unbiased integration of single cell multi-omics data

10.1101/2020.12.11.422014 ◽

2020 ◽

Author(s):

JINZHUANG DOU ◽

Shaoheng Liang ◽

Vakul Mohanty ◽

Xuesen Cheng ◽

Sangbae Kim ◽

...

Keyword(s):

Single Cell ◽

Immune Cell ◽

Cell Types ◽

Regulatory Elements ◽

Chromatin Accessibility ◽

Mouse Retina ◽

Transcriptomics Data ◽

Mouse Brain Cortex ◽

Broad Variety ◽

Data Matrices

Acquiring accurate single-cell multiomics profiles often requires performing unbiased in silico integration of data matrices generated by different single-cell technologies from the same biological sample. However, both the rows and the columns can represent different entities in different data matrices, making such integration a computational challenge that has only been solved approximately by existing approaches. Here, we present bindSC, a single-cell data integration tool that realizes simultaneous alignment of the rows and the columns between data matrices without making approximations. Using datasets produced by multiomics technologies as gold standard, we show that bindSC generates accurate multimodal co-embeddings that are substantially more accurate than those generated by existing approaches. Particularly, bindSC effectively integrated single cell RNA sequencing (scRNA-seq) and single cell chromatin accessibility sequencing (scATAC-seq) data towards discovering key regulatory elements in cancer cell-lines and mouse cells. It achieved accurate integration of both common and rare cell types (<0.25% abundance) in a novel mouse retina cell atlas generated using the 10x Genomics Multiome ATAC+RNA kit. Further, it achieves unbiased integration of scRNA-seq and 10x Visium spatial transcriptomics data derived from mouse brain cortex samples. Lastly, it demonstrated efficacy in delineating immune cell types via integrating single-cell RNA and protein data. Thus, bindSC, available at https://github.com/KChen-lab/bindSC, can be applied in a broad variety of context to accelerate discovery of complex cellular and biological identities and associated molecular underpinnings in diseases and developing organisms.

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Unbiased integration of single cell multi-omics data

10.21203/rs.3.rs-126986/v1 ◽

2020 ◽

Author(s):

Jinzhuang Dou ◽

Shaoheng Liang ◽

Vakul Mohanty ◽

Xuesen Cheng ◽

Sangbae Kim ◽

...

Keyword(s):

Single Cell ◽

Immune Cell ◽

Cell Types ◽

Regulatory Elements ◽

Chromatin Accessibility ◽

Mouse Retina ◽

Transcriptomics Data ◽

Mouse Brain Cortex ◽

Broad Variety ◽

Data Matrices

Abstract Acquiring accurate single-cell multiomics profiles often requires performing unbiased in silico integration of data matrices generated by different single-cell technologies from the same biological sample. However, both the rows and the columns can represent different entities in different data matrices, making such integration a computational challenge that has only been solved approximately by existing approaches. Here, we present bindSC, a single-cell data integration tool that realizes simultaneous alignment of the rows and the columns between data matrices without making approximations. Using datasets produced by multiomics technologies as gold standard, we show that bindSC generates accurate multimodal co-embeddings that are substantially more accurate than those generated by existing approaches. Particularly, bindSC effectively integrated single cell RNA sequencing (scRNA-seq) and single cell chromatin accessibility sequencing (scATAC-seq) data towards discovering key regulatory elements in cancer cell-lines and mouse cells. It achieved accurate integration of both common and rare cell types (<0.25% abundance) in a novel mouse retina cell atlas generated using the 10x Genomics Multiome ATAC+RNA kit. Further, it achieves unbiased integration of scRNA-seq and 10x Visium spatial transcriptomics data derived from mouse brain cortex samples. Lastly, it demonstrated efficacy in delineating immune cell types via integrating single-cell RNA and protein data. Thus, bindSC, available at https://github.com/KChen-lab/bindSC, can be applied in a broad variety of context to accelerate discovery of complex cellular and biological identities and associated molecular underpinnings in diseases and developing organisms.

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Single cell chromatin accessibility of the developmental cephalochordate

10.1101/2020.03.17.994954 ◽

2020 ◽

Author(s):

Dongsheng Chen ◽

Zhen Huang ◽

Xiangning Ding ◽

Zaoxu Xu ◽

Jixing Zhong ◽

...

Keyword(s):

Single Cell ◽

Regulatory Elements ◽

Chromatin Accessibility ◽

Developmental Trajectory ◽

Branchiostoma Floridae ◽

Cell Fates ◽

Functional Specification ◽

Great Transition ◽

Sea Squirts ◽

Chordate Ancestor

AbstractThe phylum chordata are composed of three groups: vertebrata, tunicate and cephalochordata. Single cell developmental atlas for typical species in vertebrata (mouse, zebrafish, western frog, worm) and tunicate (sea squirts) has been constructed recently. However, the single cell resolution atlas for lancelet, a living proxy of vertebrate ancestors, has not been achieved yet. Here, we profiled more than 57 thousand cells during the development of florida lancelet (Branchiostoma floridae), covering important processes including embryogenesis, organogenesis and metamorphosis. We identified stage and cluster specific regulatory elements. Additionally, we revealed the regulatory codes underlying functional specification and lineage commitment. Based on epigenetic features, we constructed the developmental trajectory for lancelet, elucidating how cell fates were established progressively. Overall, our study provides, by far, the first single cell regulatory landscape of amphioxus, which could help us to understand the heterogeneity and complexity of lancet development at single cell resolution and throw light upon the great transition from simple chordate ancestor to modern vertebrates with amazing diversity and endless forms.

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Single cell epigenomic atlas of the developing human brain and organoids

10.1101/2019.12.30.891549 ◽

2019 ◽

Cited By ~ 5

Author(s):

Ryan S. Ziffra ◽

Chang N. Kim ◽

Amy Wilfert ◽

Tychele N. Turner ◽

Maximilian Haeussler ◽

...

Keyword(s):

Human Brain ◽

Single Cell ◽

Cell Fate ◽

Cell Types ◽

Regulatory Elements ◽

Chromatin Accessibility ◽

Chromatin State ◽

Cell Type ◽

Fate Specification ◽

Cell Type Specific

AbstractDynamic changes in chromatin accessibility coincide with important aspects of neuronal differentiation, such as fate specification and arealization and confer cell type-specific associations to neurodevelopmental disorders. However, studies of the epigenomic landscape of the developing human brain have yet to be performed at single-cell resolution. Here, we profiled chromatin accessibility of >75,000 cells from eight distinct areas of developing human forebrain using single cell ATAC-seq (scATACseq). We identified thousands of loci that undergo extensive cell type-specific changes in accessibility during corticogenesis. Chromatin state profiling also reveals novel distinctions between neural progenitor cells from different cortical areas not seen in transcriptomic profiles and suggests a role for retinoic acid signaling in cortical arealization. Comparison of the cell type-specific chromatin landscape of cerebral organoids to primary developing cortex found that organoids establish broad cell type-specific enhancer accessibility patterns similar to the developing cortex, but lack many putative regulatory elements identified in homologous primary cell types. Together, our results reveal the important contribution of chromatin state to the emerging patterns of cell type diversity and cell fate specification and provide a blueprint for evaluating the fidelity and robustness of cerebral organoids as a model for cortical development.

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Droplet-based combinatorial indexing for massive scale single-cell epigenomics

10.1101/612713 ◽

2019 ◽

Cited By ~ 1

Author(s):

Caleb A. Lareau ◽

Fabiana M. Duarte ◽

Jennifer G. Chew ◽

Vinay K. Kartha ◽

Zach D. Burkett ◽

...

Keyword(s):

Single Cell ◽

Cell Types ◽

Regulatory Elements ◽

Chromatin Accessibility ◽

Droplet Microfluidics ◽

Massive Scale ◽

Single Cell Profiling ◽

Bone Marrow Derived Cells ◽

Accessible Chromatin

AbstractWhile recent technical advancements have facilitated the mapping of epigenomes at single-cell resolution, the throughput and quality of these methods have limited the widespread adoption of these technologies. Here, we describe a droplet microfluidics platform for single-cell assay for transposase accessible chromatin (scATAC-seq) for high-throughput single-cell profiling of chromatin accessibility. We use this approach for the unbiased discovery of cell types and regulatory elements within the mouse brain. Further, we extend the throughput of this approach by pairing combinatorial indexing with droplet microfluidics, enabling single-cell studies at a massive scale. With this approach, we measure chromatin accessibility across resting and stimulated human bone marrow derived cells to reveal changes in the cis- and trans- regulatory landscape across cell types and upon stimulation conditions at single-cell resolution. Altogether, we describe a total of 502,207 single-cell profiles, demonstrating the scalability and flexibility of this droplet-based platform.

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Integrated single-cell transcriptomics and chromatin accessibility analysis reveals novel regulators of mammary epithelial cell identity

10.1101/740746 ◽

2019 ◽

Cited By ~ 1

Author(s):

Nicholas Pervolarakis ◽

Quy H. Nguyen ◽

Guadalupe Gutierrez ◽

Peng Sun ◽

Darisha Jhutty ◽

...

Keyword(s):

Epithelial Cell ◽

Single Cell ◽

Mammary Epithelial Cell ◽

Cell Types ◽

Regulatory Elements ◽

Chromatin Accessibility ◽

Mammary Epithelial ◽

Secretory Cells ◽

Basal Cells ◽

Accessibility Analysis

ABSTRACTThe mammary epithelial cell (MEC) system is a bi-layered ductal epithelial network consisting of luminal and basal cells, which is maintained by a lineage of stem and progenitor cell populations. Here, we used integrated single-cell transcriptomics and chromatin accessibility analysis to reconstruct the cell types of the mouse MEC system and their underlying gene regulatory features in an unbiased manner. We define previously unrealized differentiation states within the secretory type of luminal cells, which can be divided into distinct clusters of progenitor and mature secretory cells. By integrating single-cell transcriptomics and chromatin accessibility landscapes, we identified novel cis- and trans-regulatory elements that are differentially activated in the specific epithelial cell types and our newly defined luminal differentiation states. Our work provides an unprecedented resource to reveal novel cis/trans regulatory elements associated with MEC identity and differentiation that will serve as a valuable reference to determine how the chromatin accessibility landscape changes during breast cancer.

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Single-cell chromatin and gene-regulatory dynamics of mouse nephron progenitors

10.1101/2021.10.13.464099 ◽

2021 ◽

Author(s):

Sylvia Hilliard ◽

Giovane Tortelote ◽

Hongbing Liu ◽

Chao-Hui Chen ◽

Samir S El-Dahr

Keyword(s):

Transcription Factors ◽

Single Cell ◽

Cell Fate ◽

Cell Types ◽

Regulatory Elements ◽

Chromatin Accessibility ◽

Bulk Analysis ◽

Disease States ◽

Differentiated Cells ◽

Nephron Progenitors

Background: Cis-regulatory elements (CREs), such as enhancers and promoters, and their cognate transcription factors play a central role in cell fate specification. Bulk analysis of CREs has provided insights into gene regulation in nephron progenitor cells (NPCs). However, the cellular resolution required to unravel the dynamic changes in regulatory elements associated with cell fate choices remains to be defined. Methods: We integrated single-cell chromatin accessibility (scATAC-seq) and gene expression (scRNA-seq) in embryonic E16.5 (self-renewing) and postnatal P2 (primed) mouse Six2GFP NPCs. This analysis revealed NPC diversity and identified candidate CREs. To validate these findings and gain additional insights into more differentiated cell types, we performed a multiome analysis of E16.5 and P2 kidneys. Results: CRE accessibility recovered the diverse states of NPCs and precursors of differentiated cells. Single-cell types such as podocytes, proximal and distal precursors are marked by differentially accessible CREs. Domains of regulatory chromatin as defined by rich CRE-gene associations identified NPC fate-determining transcription factors (TF). Likewise, key TF expression correlates well with its regulon activity. Young NPCs exhibited enrichment in accessible motifs for bHLH, homeobox, and Forkhead TFs, while older NPCs were enriched in AP-1, HNF1, and HNF4 motif activity. A subset of Forkhead factors exhibiting high chromatin activity in podocyte precursors. Conclusion: Defining the regulatory landscape of nephrogenesis at single-cell resolution informs the basic mechanisms of nephrogenesis and provides a foundation for future studies in disease states characterized by abnormal nephrogenesis.

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Single-cell map of diverse immune phenotypes in the acute myeloid leukemia microenvironment

Biomarker Research ◽

10.1186/s40364-021-00265-0 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Rongqun Guo ◽

Mengdie Lü ◽

Fujiao Cao ◽

Guanghua Wu ◽

Fengcai Gao ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Single Cell ◽

Myeloid Leukemia ◽

Immune Cell ◽

Immune Surveillance ◽

Cell Types ◽

Developmental Trajectory ◽

Significant Difference ◽

Cell Phenotypes ◽

Acute Myeloid

Abstract Background Knowledge of immune cell phenotypes, function, and developmental trajectory in acute myeloid leukemia (AML) microenvironment is essential for understanding mechanisms of evading immune surveillance and immunotherapy response of targeting special microenvironment components. Methods Using a single-cell RNA sequencing (scRNA-seq) dataset, we analyzed the immune cell phenotypes, function, and developmental trajectory of bone marrow (BM) samples from 16 AML patients and 4 healthy donors, but not AML blasts. Results We observed a significant difference between normal and AML BM immune cells. Here, we defined the diversity of dendritic cells (DC) and macrophages in different AML patients. We also identified several unique immune cell types including T helper cell 17 (TH17)-like intermediate population, cytotoxic CD4+ T subset, T cell: erythrocyte complexes, activated regulatory T cells (Treg), and CD8+ memory-like subset. Emerging AML cells remodels the BM immune microenvironment powerfully, leads to immunosuppression by accumulating exhausted/dysfunctional immune effectors, expending immune-activated types, and promoting the formation of suppressive subsets. Conclusion Our results provide a comprehensive AML BM immune cell census, which can help to select pinpoint targeted drug and predict efficacy of immunotherapy.

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