Biology subjects

Shang, Z.

Publications and source records attributed to Shang, Z..

3 recordsLinked to original sources

bioRxiv2018

Single-cell RNA-seq reveals dynamic transcriptome profiling in human early neural differentiation

BackgroundInvestigating cell fate decision and subpopulation specification in the context of the neural lineage is fundamental to understanding neurogenesis and neurodegenerative diseases. The differentiation process of neural-tube-like rosettes in vitro is representative of neural tube structures, which are composed of radially organized, columnar epithelial cells and give rise to functional neural cells. However, the underlying regulatory network of cell fate commitment during early neural differentiation remains elusive.\n\nResultsIn this study, we investigated the genome-wide transcriptome profile of single cells from six consecutive reprogramming and neural differentiation time points and identified cellular subpopulations present at each differentiation stage. Based on the inferred reconstructed trajectory and the characteristics of subpopulations contributing the most towards commitment to the central nervous system (CNS) lineage at each stage during differentiation, we identified putative novel transcription factors in regulating neural differentiation. In addition, we dissected the dynamics of chromatin accessibility at the neural differentiation stages and revealed active c/s-regulatory elements for transcription factors known to have a key role in neural differentiation as well as for those that we suggest are also involved. Further, communication network analysis demonstrated that cellular interactions most frequently occurred among embryoid body (EB) stage and each cell subpopulation possessed a distinctive spectrum of ligands and receptors associated with neural differentiation which could reflect the identity of each subpopulation.\n\nConclusionsOur study provides a comprehensive and integrative study of the transcriptomics and epigenetics of human early neural differentiation, which paves the way for a deeper understanding of the regulatory mechanisms driving the differentiation of the neural lineage.

developmental biology↗

bioRxiv2018

Structure of the ciliary axoneme at nanometer resolution reconstructed by TYGRESS

The resolution of subtomogram averages calculated from cryo-electron tomograms (cryo-ET) of crowded cellular environments is often limited due to signal loss in, and misalignment of the subtomograms. In contrast, single-particle cryo-electron microcopy (SP-cryo-EM) routinely reaches near-atomic resolution of isolated complexes. We developed a novel hybrid-method called \"TomographY-Guided 3D REconstruction of Subcellular Structures\" (TYGRESS) that combines cryo-ET with SP-cryo-EM to achieve close-to-nanometer resolution of complexes inside crowded environments. Using TYGRESS, we determined the native 3D structures of the intact ciliary axoneme with up to 12 [A] resolution. These results reveal many structures and details that were not visible by cryo-ET. TYGRESS is generally applicable to cellular complexes that are amenable to subtomogram averaging, bringing us a step closer to (pseudo-)atomic models of cells.\n\nOne Sentence SummaryA hybrid cryo-electron microscopy method reveals subcellular structures at unprecedented resolution.

cell biology↗

bioRxiv2018

Deconvolution of single-cell multi-omics layers reveals regulatory heterogeneity

Integrative analysis of multi-omics layers at single cell level is critical for accurate dissection of cell-to-cell variation within certain cell populations. Here we report scCAT-seq, a technique for simultaneously assaying chromatin accessibility and the transcriptome within the same single cell. We show that the combined single cell signatures enable accurate construction of regulatory relationships between cis-regulatory elements and the target genes at single-cell resolution, providing a new dimension of features that helps direct discovery of regulatory patterns specific to distinct cell identities. Moreover, we generated the first single cell integrated maps of chromatin accessibility and transcriptome in human pre-implantation embryos and demonstrated the robustness of scCAT-seq in the precise dissection of master transcription factors in cells of distinct states during embryo development. The ability to obtain these two layers of omics data will help provide more accurate definitions of \"single cell state\" and enable the deconvolution of regulatory heterogeneity from complex cell populations.

genomics↗