Biology subjects

Wan, Z.

Publications and source records attributed to Wan, Z..

3 recordsLinked to original sources

bioRxiv2018

Investigating the conformational response of the Sortilin receptor upon binding endogenous peptide- and protein ligands by HDX-MS

Sortilin is a multifunctional transmembrane neuronal receptor involved in sorting of neurotrophic factors and apoptosis signalling. So far, structural characterization of Sortilin and its endogenous ligands has been limited to crystallographic studies of Sortilin in complex with the neuropeptide Neurotensin. Here, we use hydrogen/deuterium exchange mass spectrometry to investigate the conformational response of Sortilin to binding biological ligands including the peptides Neurotensin and the Sortilin propeptide and the proteins Progranulin and pro-Nerve growth factor-{beta}. The results show that the ligands employ two binding sites inside the cavity of the {beta}-propeller of Sortilin. However, ligands have distinct differences in their conformational impact on the receptor. Interestingly, the protein ligands induce conformational stabilization in a remote membrane-proximal domain, hinting at an unknown conformational link between the ligand binding region and this membrane-proximal region of Sortilin. Our findings improves our molecular understanding of Sortilin and how it mediates diverse ligand-dependent functions important in neurobiology.

biophysics↗

bioRxiv2018

Single-cell Transcriptomic Landscape of Nucleated Cells in Umbilical Cord Blood

Umbilical cord blood (UCB) transplant is a therapeutic option for both pediatric and adult patients with a variety of hematologic diseases such as several types of blood cancers, myeloproliferative disorders, genetic diseases, and metabolic disorders. However, the level of cellular heterogeneity and diversity of nucleated cells in the UCB has not yet been assessed in an unbiased and systemic fashion. In the current study, nucleated cells from UCB were subjected to single-cell RNA sequencing, a technology enabled simultaneous profiling of the gene expression signatures of thousands of cells, generating rich resources for further functional studies. Here, we report the transcriptomic maps of 19,052 UCB cells, covering 11 major cell types. Many of these cell types are comprised of distinct subpopulations, including distinct signatures in NK and NKT cell types in the UCB. Pseudotime ordering of nucleated red blood cells (NRBC) identifies wave-like activation and suppression of transcription regulators, leading to a polarized cellular state, which may reflect the NRBC maturation. Progenitor cells in the UBC also consist two subpopulations with divergent transcription programs activated, leading to specific cell-fate commitment. Collectively, we provide this comprehensive single-cell transcriptomic landscape and show that it can uncover previously unrecognized cell types, pathways and gene expression regulations that may contribute to the efficacy and outcome of UCB transplant, broadening the scope of research and clinical innovations.

genomics↗

bioRxiv2018

Identification and quantification of Lyme pathogen strains by deep sequencing of outer surface protein C (ospC) amplicons

Mixed infection of a single tick or host by Lyme disease spirochetes is common and a unique challenge for diagnosis, treatment, and surveillance of Lyme disease. Here we describe a novel protocol for differentiating Lyme strains based on deep sequencing of the hypervariable outer-surface protein C locus (ospC). Improving upon the traditional DNA-DNA hybridization method, the next-generation sequencing-based protocol is high-throughput, quantitative, and able to detect new pathogen strains. We applied the method to over one hundred infected Ixodes scapularis ticks collected from New York State, USA in 2015 and 2016. Analysis of strain distributions within individual ticks suggests an overabundance of multiple infections by five or more strains, inhibitory interactions among co-infecting strains, and presence of a new strain closely related to Borreliella bissettiae. A supporting bioinformatics pipeline has been developed. With the newly designed pair of universal ospC primers targeting intergenic sequences conserved among all known Lyme pathogens, the protocol could be used for culture-free identification and quantification of Lyme pathogens in wildlife and clinical specimens across the globe.

microbiology↗