Biology subjects

Wang, R. T.

Publications and source records attributed to Wang, R. T..

3 recordsLinked to original sources

bioRxiv2022

Single nuclei transcriptomics of muscle reveals intra-muscular cell dynamics linked to dystrophin loss and rescue

In Duchenne muscular dystrophy, dystrophin loss leads to chronic muscle damage, dysregulation of repair, fibro-fatty replacement, and weakness. We develop methodology to efficiently isolate individual nuclei from frozen skeletal muscle, allowing single nuclei sequencing of irreplaceable archival samples from small samples. We apply this method to identify cell and gene expression dynamics within human DMD and mdx mouse muscle, characterizing treatment effects of dystrophin rescue by exon skipping therapy at single nuclei resolution. DMD exon 23 skipping events are directly observed and increased in myonuclei from treated mice. We describe partial rescue of type IIa and IIx myofibers, expansion of a novel MDSC-like myeloid population, recovery of repair/remodeling M2-macrophage, and repression of inflammatory POSTN1+ fibroblasts in response to exon skipping and partial dystrophin restoration. Use of this method enables exploration of cellular and transcriptomic mechanisms of dystrophin loss and repair.

genetics↗

bioRxiv2020

Binding strength and hydrogen bond numbers between Covid-19 RBD and HVR of antibody

The global battle against the Covid-19 pandemic relies strongly on the human defence of antibody, which is assumed to bind the antigens Receptor Binding Domain with its Hypervariable Region. Due to the similarity to other viruses such as SARS, however, our understanding of the antibody-virus interaction has been largely limited to the genomic sequencing, which poses serious challenges to the containment, vaccine exploration and rapid serum testing. Based on the physical/chemical nature of the interaction, infrared spectroscopy was employed to reveal the binding disparity, when unusual temperature dependence was discovered from the 1550cm-1 absorption band, attributed to the hydrogen bonds by carboxyl/amino groups, binding the SARS-CoV-2 spike protein and closely resembled SARS-CoV-2 or SARS-CoV-1 antibodies. The infrared absorption intensity, associated with the number of hydrogen bonds, was found to increase sharply between 27{degrees}C and 31{degrees}C, with the relative absorbance matches at 37{degrees}C the hydrogen bonding numbers of the two antibody types (19 vs 12). Meanwhile the ratio of bonds at 27{degrees}C, calculated by thermodynamic exponentials rather than by the laymans guess, produces at least 5% inaccuracy. As a result, the specificity of the SARS-CoV-2 antibody will be more conclusive beyond 31{degrees}C, instead of at the usual room temperature of 20{degrees}C - 25{degrees}C, when the vaccine research and antibody diagnosis would likely be undermined. Beyond genomic sequencing, the temperature dependence, as well as the bond number match at 37{degrees}C between relative absorbance and the hydrogen bonding numbers of the two antibody types, are not only of clinical significance in particular, but also of a sample for the physical/chemical understanding of the vaccine-antibody interactions in general.

microbiology↗

bioRxiv2019

Pooled analysis of radiation hybrids identifies loci for growth and drug action in mammalian cells

Genetic screens in mammalian cells commonly focus on loss-of-function approaches. To evaluate the phenotypic consequences of extra gene copies, we used bulk segregant analysis (BSA) of radiation hybrid (RH) cells. We constructed six pools of RH cells, each consisting of ~2500 independent clones, and placed the pools under selection in media with or without paclitaxel. Low pass sequencing identified 859 growth loci, 38 paclitaxel loci, 62 interaction loci and 3 loci for mitochondrial abundance at genome-wide significance. Resolution was measured as ~30 kb, close to single-gene. Divergent properties were displayed by the RH-BSA growth genes compared to those from loss-of-function screens, refuting the balance hypothesis. In addition, enhanced retention of human centromeres in the RH pools suggests a new approach to functional dissection of these chromosomal elements. Pooled analysis of RH cells showed high power and resolution and should be a useful addition to the mammalian genetic toolkit.

genetics↗