Biology subjects

Zhong, T.

Publications and source records attributed to Zhong, T..

5 recordsLinked to original sources

bioRxiv2023

Site-specific Effector Protein Functionalization to Create Bead-based Avidity Model Systems

The cooperative effect of multiple affinity binding interactions creating a stable bond, known as avidity, is a universal biological phenomenon seen in diverse systems. For example, avidity based biomolecular interactions are particularly important in assessing the potency of potential drugs such as monoclonal antibodies, chimeric antigen receptor (CAR) T-cell, or Natural Killer, cells to treat cancer or engineering microbes with cell surface immobilized enzyme complexes for consolidated bioprocessing (CBP) of cellulosic biomass to fuels and chemicals. However, predicting or measuring avidity based on in vitro single affinity interactions with non-complexed protein-ligand binding model systems has limitations and often fails to describe the avidity effects observed in vivo with cell surface complexed proteins interacting with multivalent ligands at solid interfaces. Acoustic force spectroscopy (AFS) based assays have recently emerged as a reliable method for direct avidity measurements, expressed as adhesion or rupture forces, which positively correlate with in vivo avidity interactions. However, to better understand and model avidity, in particular for cell-cell interactions and to correlate it with classical binding affinity, a cell mimetic model system with controlled avidity-related properties is needed. Here, we present a method for producing such a cell mimetic model system using "effector beads" that can be used in AFS-based avidity assays or any other bead-based avidity assay. The protein of interest is heterologously expressed and biotinylated in vivo in E. coli, purified, and subsequently tethered with streptavidin coated micron-sized beads to create effector beads. Our experimental results, combined with simulations of the multivalent binding phenomena, demonstrate the dependency of bead rupture force on its receptor protein surface density and force loading rate as well as the intrinsic kinetic binding parameters of the protein-ligand system of interest. These insights provide valuable information for designing future effector bead assays and cell avidity measurements for screening and characterization purposes for diverse applications.

bioengineering↗

bioRxiv2022

eccDNA Atlas: a comprehensive resource of eccDNA catalog

Extrachromosomal circular DNA (eccDNA) represents a large category of nonmitochondrial and nonplasmid circular extrachromosomal DNA playing an indispensable role in various aspects such as tumorigenesis, immune responses, liquid biopsy, etc. However, characteristic and functions of eccDNA are fragmented, hiding behind abundant literatures and massive whole-genome sequencing (WGS) data, which have not been sufficiently used for identification of eccDNAs. Therefore, establishing an integrated repository portal is essential for identifying and analyzing eccDNAs. Here, we developed eccDNA Atlas (http://lcbb.swjtu.edu.cn/eccDNAatlas), a user-friendly database of eccDNAs that aims to provide a high-quality and integrated resource for browsing, searching and analyzing eccDNAs from multiple species. eccDNA Atlas currently containing 630,434 eccDNAs and 7,774 ecDNAs manually curated from literatures and 1,105 ecDNAs predicted by AmpliconArchitect based on WGS data involved in 66 diseases, 57 tissue and 319 cell lines. The content of each eccDNA entry included multiple aspects such as sequence, disease, function, characteristic, validation strategies, etc. Furthermore, abundant annotations and analyzing utilities were provided to explore existed eccDNAs in eccDNA Atlas or user-defined eccDNAs including oncogenes, typical enhancers, super enhancers, gene expression, survival, and genome visualization. Based on these resources, eccDNA Atlas will significantly improve our understanding of eccDNAs and serve as an important catalyst for future research of eccDNAs.

bioinformatics↗

bioRxiv2022

A novel non-invasive biomarker based on oral microbiome dysbiosis for detection of Community-Acquired Pneumonia

BackgroundEarly diagnosis of pathogenic bacteria is crucial for the treatment of community-acquired pneumonia (CAP), but conventional diagnostics are limited by sampling difficulties. Oral microbiota has also been explored as a noninvasive biomarker of lung diseases, but its role in CAP has been neglected. We aimed to investigate whether the oral bacteria can be novel non-invasive biomarkers for CAP. MethodsOral swab samples were collected from 29 patients with CAP and 26 healthy volunteers and characterized based on clinical parameters and 16S rRNA profiling of oral bacteria. A predict functional profiling was performed for the functional and metabolic changes in oral microbial communities. ResultsOral microbial of patients with CAP had a lower diversity than healthy group. And the dominant bacteria were Streptococcus, Prevotella and Neisseria in CAP. Higher abundance of Prevotella (particularly Prevotella_melaninogenica), Veillonella and Campylobacter, and lower abundance of Neisseria and Fusobacterium were detected in CAP group. Analysis of the functional potential of oral microbiota demonstrated that the pathway involving infectious disease was overrepresented in the CAP groups relative to that in the healthy controls. ConclusionsOral microbial dysbiosis was found in patients with CAP, supporting the use of this non-invasive specimen for biomarkers of CAP. HighlightsO_LIOral microbial diversity was significantly lower in community-acquired pneumonia (CAP) patients than healthy controls. C_LIO_LIGenera Neisseria and Fusobacterium were decreased, while genera Prevotella, Veillonella and Campylobacter were increased in CAP versus healthy controls. C_LIO_LIOral microbiota-based biomarkers can serve as a promising non-invasive tool for the detection of CAP. C_LI

microbiology↗

bioRxiv2021

Efficiently, accurately, intelligently dissecting bamboo: characteristic of vascular bundle in Phyllostachys

A comprehensive understanding of vascular bundles is the key to elucidate the excellent intrinsic mechanical properties of bamboo. This research aims to investigate the gradient distribution of fiber volume fraction and the gradient changes in the shape of vascular bundles along the radial axis in Phyllostachys. We constructed a universal transfer-learning-based vascular bundle detection model with high precision of up to 96.97%, which can help to acquire the characteristics of vascular bundles quickly and accurately. The total number of vascular bundles, total fiber sheath area, the length, width and area of fiber sheath of individual vascular bundles within the entire cross-section were counted, and the results showed that these parameters had a strongly positive linear correlation with the outer circumference and wall thickness of bamboo culms, but the fiber volume fraction (around 25.5 %) and the length-to-width ratio of the vascular bundles (around 1.226) were relatively constant. Furthermore, we layered the cross section of bamboo according to the wall thickness finely and counted the characteristics of vascular bundle in each layer. The results showed that the radial distribution of fiber volume fraction decreased exponentially, the radial distribution of the length-to-width ratio of vascular bundle decreased quadratically, the radial distribution of the width of vascular bundle increased linearly. The trends of the gradient change in vascular bundles characteristics were found highly consistent among 29 bamboo species in Phyllostachys. One sentence summaryA universal vascular bundle detection model can efficiently dissect vascular bundles in Phyllostachys, and the radial gradient change of vascular bundles in cross-section are found highly consistent.

plant biology↗

bioRxiv2021

Renal Interstitial Cells Promote Nephron Regeneration by Secreting Prostaglandin E2

In organ regeneration, progrnitor and stem cells reside in their native microenvironment, which provides dynamic physical and chemical cues essential to their survival, proliferation and differentiation. However, what kind of cells provide a native microenvironment for renal progenitor cells has not been clarified. Here, single-cell sequencing of zebrafish kidney revealed that fabp10 was a marker of renal interstitial cells (RICs), and the Tg(fabp10a:GFP) transgenic line can specifically label RICs in zebrafish kidney. The formation of RICs and nephrons are closely accompanied during nephron regeneration. RICs form a network to wrap the renal progenitor cell aggregates. RICs in close contact with cell aggregates express cyclooxygenase 2 and secrete prostaglandin 2 (PGE2). Inhibiting PGE2 production prevented nephrogenesis by reducing the proliferation and differentiation of progenitor cell aggregates. PGE2 promoted maturation of the nephron by activating the WNT signaling pathway in progenitor cell aggregates in cooperation with Wnt4a. These findings suggest that RICs provide a necessary microenvironment for rapid nephrogenesis during nephron regeneration.

developmental biology↗