Biology subjects

Zhai, H.

Publications and source records attributed to Zhai, H..

23 records · Page 2Linked to original sources

bioRxiv2021

Cryo-electron tomography of ASC signalling sites in pyroptotic cells

NLRP3 induces caspase-1-dependent pyroptotic cell death to drive inflammation. Aberrant activity of NLRP3 occurs in many human diseases. NLRP3 activation induces ASC polymerization into a single, micron-scale perinuclear punctum. Higher resolution imaging of this signaling platform is needed to understand how it induces pyroptosis. Here, we apply correlative cryo-light microscopy and cryo-electron tomography to visualize ASC/caspase-1 in NLRP3-activated cells. The puncta are composed of branched ASC filaments, with a tubular core formed by the pyrin domain. Ribosomes and Golgi-like vesicles permeate the filament network, consistent with roles for these organelles in NLRP3 activation. Mitochondria are not associated with ASC but have outer-membrane discontinuities the same size as gasdermin D pores, consistent with our data showing gasdermin D associates with mitochondria and contributes to mitochondrial depolarization. One-Sentence SummaryElectron tomography of frozen cells reveals the ultrastructure of ASC specks and gasdermin D pores in adjacent mitochondria.

immunology↗

bioRxiv2020

obaDIA: one-step biological analysis pipeline for quantitative proteomics data from data independent acquisition mass spectrometry

MotivationData mining and data quality evaluation are indispensable constituents of quantitative proteomics, but few integrated tools available. ResultsWe introduced obaDIA, a one-step pipeline to generate visualizable and comprehensive results for quantitative proteomics data. obaDIA supports fragment-level, peptide-level and protein-level abundance matrices from DIA technique, as well as protein-level abundance matrices from other quantitative proteomic techniques. The result contains abundance matrix statistics, differential expression analysis, protein functional annotation and enrichment analysis. Additionally, enrichment strategies which use total proteins or expressed proteins as background are optional, and HTML based interactive visualization for differentially expressed proteins in the KEGG pathway is offered, which helps biological significance mining. In short, obaDIA is an automatic tool for bioinformatics analysis for quantitative proteomics. AvailabilityobaDIA is freely available from https://github.com/yjthu/obaDIA.git. Contactdingxiaojun@e-omics.com

bioinformatics↗

bioRxiv2020

Experimental study of tissue-engineered urethra with collagen / chitosan composite as scaffolds

In this article we investigated the preparation of tissue-engineered urethra by using the urethral epithelial subculture cells of male New Zealand young rabbits. We inoculated the epithelial cells of urinary mucosa of male New Zealand young rabbits on collagen, chitosan and collagen chitosan composite as scaffolds to prepare tissue-engineered urethra. The results of inverted phase contrast microscope, HE staining and scanning electron microscope of three kinds of tissue-engineered urethra were compared. Whats more, we reported a new method for quantitative and rapid detection of epithelial cell activity of urinary mucosa in situ by Interactive Laser Cytometer. The collagen chitosan composite was more similar to the extracellular matrix of mammalian. Its three-dimensional porous structure had a high area volume ratio, which was conducive to cell adhesion, growth and metabolism. In vitro, the urethral epithelial cells had been cultured on collagen chitosan composite, and the tissue-engineered urethra was successfully prepared, which laid a solid foundation for further in vivo experiments.

bioengineering↗

bioRxiv2019

Whole genome base-wise aggregation and functional prediction for human non-coding regulatory variants

Predicting the functional or pathogenic regulatory variants in the human non-coding genome facilitates the interpretation of disease causation. While numerous prediction methods are available, their performance is inconsistent or restricted to specific tasks, which raises the demand of developing comprehensive integration for those methods. Here, we compile whole genome base-wise aggregations, regBase, that incorporate largest prediction scores. Building on different assumptions of causality, we train three composite models to score functional, pathogenic and cancer driver non-coding regulatory variants respectively. We demonstrate the superior and stable performance of our models using independent benchmarks and show great success to fine-map causal regulatory variants. We believe that regBase database together with three composite models will be useful in different areas of human genetic studies, such as annotation-based casual variant fine-mapping, pathogenic variant discovery as well as cancer driver mutation identification. regBase is freely available at https://github.com/mulinlab/regBase.

genomics↗

bioRxiv2018

Elongator is required for root stem cell maintenance by regulating SHORT ROOT transcription

SHORTROOT (SHR) is essential for stem cell maintenance and radial patterning in Arabidopsis thaliana roots, but how its expression is regulated is still unknown. Here, we report that Elongator regulates the transcription of SHR. The depletion of Elongator drastically reduced SHR expression and led to defective root stem cell maintenance and radial patterning. The importance of the nuclear localization of Elongator for its functioning, together with the insensitivity of the elp1 mutant to the transcription elongation inhibitor 6-azauracil and the direct interaction of the ELP4 subunit with the C-terminal domain of RNA polymerase II (RNAPII CTD), support the notion that Elongator plays important roles in transcription elongation. Indeed, we found that ELP3 associates with the pre-mRNA of SHR and that mutation of Elongator reduces the enrichment of RNAPII on the SHR gene body. Moreover, Elongator interacted in vivo with SUPPRESSOR OF Ty4 (SPT4), a well-established transcription elongation factor that was recruited to the SHR locus. Together, these results demonstrate that Elongator acts in concert with SPT4 to regulate the transcription of SHR.

plant biology↗