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Wang, S.-W.

Publications and source records attributed to Wang, S.-W..

8 recordsLinked to original sources

Salinity impacted microbial carbonate precipitation mechanisms of modern microbialites in peritidal zone

Microbialites, ancient records of microbial activity, serve as significant indicators of environmental change. This study examined microbialites from the peritidal zone of three tide pools at Fongchueisha, Hengchun, Taiwan, to investigate the impact of salinity on microbial community composition and carbonate precipitation mechanisms. Microbial samples were collected across varying salinity gradients over multiple timepoints and analyzed using next-generation sequencing of bacterial 16S and eukaryotic 18S rRNA genes. Our findings reveal that the microbial communities in higher salinity environments exhibited significant shifts, with increased relative abundance of ureolytic bacteria and ammonifying microorganisms, such as Myxococcota and Actinobacteriota. This suggests the presence of diverse microbial carbonate precipitation mechanisms beyond photosynthesis, including ureolysis and ammonification. Furthermore, our results show that changes in the composition of cyanobacteria and diatoms were influenced by salinity, with heterocystous cyanobacteria (e.g., Nostocales) dominating low-salinity environments, and non-heterocystous cyanobacteria (e.g., Synechococcales) prevailing in higher salinity environments. Functional predictions reveal that microbial communities in high-salinity environments were enriched in anaerobic metabolic pathways, including pyruvate fermentation and the urea cycle. These findings highlight the significant role of salinity in influencing microbial composition and metabolic pathways, shaping carbonate precipitation processes in microbialites. ImportanceThe study focuses on the impact of environmental salinity on microbial community composition and carbonate precipitation mechanisms within modern microbialites, based on an analysis of samples from three tide pools with different salinity levels collected at five time points throughout the year. Using next-generation sequencing of bacterial 16S and eukaryotic 18S rRNA genes, we identified key shifts in microbial communities along salinity gradients and explored diverse microbial processes involved in carbonate precipitation. This work enhances our understanding of microbial ecosystems within modern microbialites and their response to environmental changes. Additionally, our study provides insight into ancient biogeochemical processes, with implications for interpreting microbial metabolism in carbonate precipitation across different salinity regimes.

microbiology↗

A mouse model with high clonal barcode diversity for joint lineage, transcriptomic, and epigenomic profiling in single cells

Cellular lineage histories along with their molecular states encode fundamental principles of tissue development and homeostasis. Current lineage-recording mouse models have limited barcode diversity and poor single-cell lineage coverage, thus precluding their use in tissues composed of millions of cells. Here, we developed DARLIN, an improved Cas9 barcoding mouse line that utilizes terminal deoxynucleotidyl transferase (TdT) to enhance insertion events over 30 CRISPR target sites, stably integrated into 3 distinct genomic loci. DARLIN is inducible, has an estimated ~1018 lineage barcodes across tissues, and enables detection of usable barcodes in ~60% of profiled single cells. Using DARLIN, we examined fate priming within developing hematopoietic stem cells (HSCs) and revealed unique features of HSC migration. Additionally, we adapted a method to jointly profile DNA methylation, chromatin accessibility, gene expression, and lineage information in single cells. DARLIN will enable widespread high-resolution study of lineage relationships and their molecular signatures in diverse tissues and physiological contexts.

developmental biology↗

Impact of Glycosylation on SARS-CoV-2 Infection and Broadly Protective Vaccine Design

A major challenge to end the pandemic caused by SARS-CoV-2 is to develop a broadly protective vaccine. As the key immunogen, the spike protein is frequently mutated with conserved epitopes shielded by glycans. Here, we reveal that spike glycosylation has site-differential effects on viral infectivity and lung epithelial cells generate spike with more infective glycoforms. Compared to the fully glycosylated spike, immunization of spike protein with N-glycans trimmed to the monoglycosylated state (Smg) elicits stronger immune responses and better protection for hACE2 transgenic mice against variants of concern. In addition, a broadly neutralizing monoclonal antibody was identified from the Smg immunized mice, demonstrating that removal of glycan shields to better expose the conserved sequences is an effective and simple approach to broad-spectrum vaccine development. One-Sentence SummaryRemoving glycan shields to expose conserved epitopes is an effective approach to develop a broad-spectrum SARS-CoV-2 vaccine.

microbiology↗

Learning dynamics by computational integration of single cell genomic and lineage information

A goal of single cell genome-wide profiling is to reconstruct dynamic transitions during cell differentiation, disease onset, and drug response. Single cell assays have recently been integrated with lineage tracing, a set of methods that identify cells of common ancestry to establish bona fide dynamic relationships between cell states. These integrated methods have revealed unappreciated cell dynamics, but their analysis faces recurrent challenges arising from noisy, dispersed lineage data. Here, we develop coherent, sparse optimization (CoSpar) as a robust computational approach to infer cell dynamics from single-cell genomics integrated with lineage tracing. CoSpar is robust to severe down-sampling and dispersion of lineage data, which enables simpler, lower-cost experimental designs and requires less calibration. In datasets representing hematopoiesis, reprogramming, and directed differentiation, CoSpar identifies fate biases not previously detected, predicting transcription factors and receptors implicated in fate choice. Documentation and detailed examples for common experimental designs are available at https://cospar.readthedocs.io/.

developmental biology↗

Broad Dengue Neutralization in Mosquitoes Expressing an Engineered Antibody

With dengue virus (DENV) becoming endemic in tropical and subtropical regions worldwide, there is a pressing global demand for effective strategies to control the mosquitoes that spread this disease. Recent advances in genetic engineering technologies have made it possible to create mosquitoes with reduced vector competence, limiting their ability to acquire and transmit pathogens. Here we describe the development of Aedes aegypti mosquitoes synthetically engineered to impede vector competence to DENV. These mosquitoes express a gene encoding an engineered single-chain variable fragment derived from a broadly neutralizing DENV human monoclonal antibody and have significantly reduced viral infection, dissemination, and transmission rates for all four major antigenically distinct DENV serotypes. Importantly, this is the first engineered approach that targets all DENV serotypes, which is crucial for effective disease suppression. These results provide a compelling route for developing effective genetic-based DENV control strategies, which could be extended to curtail other arboviruses.\n\nSignificance StatementHere we describe the development of Ae. aegypti mosquitoes synthetically engineered to impede vector competence to multiple serotypes of DENV. Given the global significance of DENV, these mosquitoes may be used to curtail Dengue transmission by this potent vector.

bioengineering↗

Emergent oscillations in dense adaptive cell populations

Collective oscillations of cells in a population appear under diverse biological contexts. Here, we establish a set of common principles by categorising the response of individual cells against a time-varying signal. A positive intracellular signal relay of sufficient gain from participating cells is required to sustain the oscillations, together with phase matching. The two conditions yield quantitative predictions for the onset cell density and frequency in terms of measured single-cell and signal response functions. Through mathematical constructions, we show that cells that adapt to a constant stimulus fulfil the phase requirement by developing a leading phase in an active frequency window that enables cell-to-signal energy flow. Analysis of dynamical quorum sensing in several cellular systems with increasing biological complexity reaffirms the pivotal role of adaptation in powering oscillations in an otherwise dissipative cell-to-cell communication channel. The physical conditions identified also apply to synthetic oscillatory systems.

biophysics↗

Revealing evolutionary constraints on proteins through sequence analysis

Alignments of large numbers of protein sequences have revealed \"sectors\" of collectively coevolving amino acids in several protein families. Here, we show that selection acting on any relevant physical property of a protein, e.g. the elastic energy of an important conformational change, can give rise to such a sector. We demonstrate that the main signature of these physical sectors lies in the smalleigenvalue modes of the covariance matrix of the selected sequences. This simple, generic model leads us to propose a principled method to identify sectors, along with the magnitudes of mutational effects, from sequence data.

biophysics↗

Engineered resistance to Zika virus in transgenic Ae. aegypti expressing a polycistronic cluster of synthetic miRNAs

Recent Zika virus (ZIKV) outbreaks have highlighted the necessity for development of novel vector control strategies to combat arboviral transmission, including genetic versions of the sterile insect technique, artificial infection with Wolbachia to reduce population size and/or vectoring competency, and gene drive based methods. Here, we describe the development of mosquitoes synthetically engineered to impede vector competence to ZIKV. We demonstrate that a polycistronic cluster of engineered microRNAs (miRNAs) targeting ZIKV is expressed and fully processed following a blood meal in Ae. aegypti, ensuring the formation of mature synthetic miRNAs in the midgut where ZIKV resides in the early stages of infection. Critically, we demonstrate that engineered Ae. aegypti mosquitoes harboring the anti-ZIKV transgene have significantly reduced viral infection, dissemination, and transmission rates of ZIKV. Taken together, these compelling results provide a promising path forward for development of effective genetic-based ZIKV control strategies, which could potentially be extended to curtail other arboviruses.\n\nOne Sentence SummaryHere we describe the generation of Ae. aegypti mosquitoes that are engineered to confer reduced vector competence to Zika virus (ZIKV) and we discuss how such engineering approach can be used to combat the major health burden of ZIKV and potentially other arboviruses in the future.

synthetic biology↗