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Biology subjects

Jiang, Y.

Publications and source records attributed to Jiang, Y..

At least 415 records · Page 23Linked to original sources

Genomic insights into present local adaptation and future climate change vulnerability of a keystone forest tree species in East Asian

Rapid global climate change is posing a huge threat to biodiversity. Assessments of the adaptive capacity for most taxa is usually performed on the species as a whole, but fails to incorporate intraspecific adaptive variation that may play a fundamental role in buffering future shifting climates. Here we generate a chromosome-scale genome assembly for Populus koreana, a pioneer and keystone tree species in East Asia temperate forests. We also obtain whole-genome sequences of 230 individuals collected from 24 natural populations. An integration of population genomics and environmental variables was performed to reveal the genomic basis of local adaptation to diverse climate variable. We identify a set of climate-associated single nucleotide polymorphisms (SNPs), insertions-deletions (Indels) and structural variations (SVs), in particular numerous adaptive non-coding variants distributed across the genome of P. koreana. We incorporate these variants into an environmental modelling scheme to predict spatiotemporal responses of P. koreana to future climate change. Our results highlight the insights that the integration of genomic and climate data can shed on the future evolutionary adaptive capacities of a species to changing environmental conditions.

evolutionary biology↗

A toolkit of highly selective and sensitive genetically encoded neuropeptide sensors

Neuropeptides are key signaling molecules in the endocrine and nervous systems that regulate many critical physiological processes, including energy balance, sleep and circadian rhythms, stress, and social behaviors. Understanding the functions of neuropeptides in vivo requires the ability to monitor their dynamics with high specificity, sensitivity, and spatiotemporal resolution; however, this has been hindered by the lack of direct, sensitive and non-invasive tools. Here, we developed a series of GRAB (G protein-coupled receptor activation-based) sensors for detecting somatostatin (SST), cholecystokinin (CCK), corticotropin-releasing factor (CRF), neuropeptide Y (NPY), neurotensin (NTS), and vasoactive intestinal peptide (VIP). These fluorescent sensors utilize the corresponding GPCRs as the neuropeptide-sensing module with the insertion of a circular-permutated GFP as the optical reporter. This design detects the binding of specific neuropeptides at nanomolar concentration with a robust increase in fluorescence. We used these GRAB neuropeptide sensors to measure the spatiotemporal dynamics of endogenous SST release in isolated pancreatic islets and to detect the release of both CCK and CRF in acute brain slices. Moreover, we detect endogenous CRF release induced by stressful experiences in vivo using fiber photometry and 2-photon imaging in mice. Together, these new sensors establish a robust toolkit for studying the release, function, and regulation of neuropeptides under both physiological and pathophysiological conditions.

neuroscience↗

Novel Methods for Multi-ancestry Polygenic Prediction and their Evaluations in 3.7 Million Individuals of Diverse Ancestry

Polygenic risk scores (PRS) increasingly predict complex traits, however, suboptimal performance in non-European populations raise concerns about clinical applications and health inequities. We developed CT-SLEB, a powerful and scalable method to calculate PRS using ancestry-specific GWAS summary statistics from multi-ancestry training samples, integrating clumping and thresholding, empirical Bayes and super learning. We evaluate CT-SLEB and nine-alternatives methods with large-scale simulated GWAS ([~]19 million common variants) and datasets from 23andMe Inc., the Global Lipids Genetics Consortium, All of Us and UK Biobank involving 5.1 million individuals of diverse ancestry, with 1.18 million individuals from four non-European populations across thirteen complex traits. Results demonstrate that CT-SLEB significantly improves PRS performance in non-European populations compared to simple alternatives, with comparable or superior performance to a recent, computationally intensive method. Moreover, our simulation studies offer insights into sample size requirements and SNP density effects on multi-ancestry risk prediction.

genetics↗

Structure and influence in an interconnected world: neurocomputational mechanism of real-time distributed learning on social networks

Many social species are embedded on social networks, including our own. The structure of social networks shapes our decisions by constraining what information we learn and from whom. But how does the brain incorporate social network structures into learning and decision-making processes, and how does learning in networked environments differ from learning from isolated partners? Combining a real-time distributed learning task with computational modeling, fMRI, and social network analysis, we investigated the process by which humans learn from observing others decisions on 7-node networks with varying topological structures. We show that learning on social networks can be realized by means similar to the well-established reinforcement learning algorithm, supported by an action prediction error encoded in the lateral prefrontal cortex. Importantly, learning is flexibly weighted toward well-connected neighbors, according to activity in the dorsal anterior cingulate cortex, but only insofar as neighbors actions vary in their informativeness. These data suggest a neurocomputational mechanism of network-dependent filtering on the sources of information, which may give rise to biased learning and the spread of misinformation in an interconnected society.

neuroscience↗

Interface resistance of biomolecular condensates

A hallmark of biomolecular condensates formed via liquid-liquid phase separation is that they dynamically exchange material with their surroundings, and this process can be crucial to condensate function. Intuitively, the rate of exchange can be limited by the flux from the dilute phase or by the mixing speed in the dense phase. Surprisingly, a recent experiment suggests that exchange can also be limited by the dynamics at the droplet interface, implying the existence of an "interface resistance". Here, we first derive an analytical expression for the timescale of condensate material exchange, which clearly conveys the physical factors controlling exchange dynamics. We then utilize sticker-spacer polymer models to show that interface resistance can arise when incident molecules transiently touch the interface without entering the dense phase, i.e., the molecules "bounce" from the interface. Our work provides insight into condensate exchange dynamics, with implications for both natural and synthetic systems.

biophysics↗

Structural insights into the peptide selectivity and activation of human neuromedin U receptors

Neuromedin U receptors (NMURs), including NMUR1 and NMUR2, are a group of Gq/11-coupled G protein-coupled receptors (GPCRs) related to pleiotropic physiological functions. Upon stimulation by two endogenous neuropeptides, neuromedin U and S (NMU and NMS) with similar binding affinities, NMUR1 and NMUR2 primarily display distinct peripheral tissue and central nervous system (CNS) functions, respectively, due to their distinct tissue distributions. These NMU receptors have triggered extensive attention as drug targets for obesity and immune inflammation. Specifically, selective agonists for NMUR1 in peripheral tissue show promising long-term anti-obesity effects with fewer CNS-related side effects. However, the mechanisms of peptide binding specificity and receptor activation remain elusive due to the lack of NMU receptor structures, which hamper drug design targeting NMU receptors. Here, we report four cryo-electron microscopy structures of Gq chimera-coupled NMUR1 and NMUR2 bound with NMU and NMS. These structures present the conserved overall peptide-binding mode and reveal the mechanism of peptide selectivity for specific NMURs, as well as the common activation mechanism of the NMUR subfamily. Together, these findings provide insights into the molecular basis of the peptide recognition selectivity and offer a new opportunity for designing selective drugs targeting NMURs.

biophysics↗

CRISPR-Detector: Fast and Accurate Detection, Visualization, and Annotation of Genome Wide Mutations Induced by Gene Editing Events

The leading edge of genome editing, driven by CRISPR/Cas technology, is revolutionizing biotechnologies. In pace with the burst of novel genome editing methods, bioinformatic tools to monitor the on/off-target events need to be more evolved as well. Existing tools suffer from limitations in speed and scalability, and they especially struggle with whole genome sequencing (WGS) data analysis which has the potential to detect off-target mutations at a genome-wide level via an unbiased manner. Here, we introduce our CRISPR-detector tool, which is a web-hosted or locally deployable pipeline with five key innovations: 1) optimized scalability allowing for WGS data analysis beyond BED (Browser Extensible Data) file-defined regions; 2) improved accuracy benefiting from haplotype-based variant calling to handle sequencing errors; 3) treated and control sample co-analysis to remove background variants existing prior to genome editing; 4) integrated structural variation (SV) calling; and 5) functional and clinical annotation of editing-induced mutations.

bioinformatics↗

PKD-1 Signaling Is Required for the Maintenance of CSCs with Epithelial-mesenchymal Plasticity in Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors (pNETs) are extremely heterogeneous and highly vascularized neoplasms that arise from endocrine cells in the pancreas. pNETs harbor a subpopulation of stem cell-like cancer cells (cancer stem cells/CSCs), which contribute to intratumoral heterogeneity and promote tumor maintenance and recurrence. In this study we demonstrated that CSCs in human pNETs co-expressed PKD-1 and CD44. We further identified PKD-1 signaling as a critical pathway in the regulation of CSC maintenance in pNET cells. PKD-1 signaling regulated the expression of a CSC-related gene signature and promoted CSC self-renewal. Intriguingly, pharmacological or genetic disruption of PKD-1 signaling in human pNET cells impaired lysophosphatidic acid-induced expression of genes associated with epithelial to mesenchymal transition (EMT), specifically E-cadherin and vimentin. This study indicates that PKD-1 signaling is essential for the maintenance of a subpopulation of CSCs in pNETs at an intermediate state along the epithelial-mesenchymal spectrum, thereby leading to a CSC phenotype with plasticity and partial EMT. Inhibiting the PKD-1 pathway may facilitate the elimination of CSC subpopulations to curb pNET progression, therapeutic resistance and metastasis. Given that the signaling networks associated with CSC maintenance and EMT are complex and extend across multiple levels of gene regulation, this study provides insight into signaling regulation of partial EMT in determining CSC fate and aids in developing potential therapeutic strategies that target different subsets of CSCs in a variety of cancers.

cancer biology↗

Arbidol inhibits esophageal squamous cell carcinoma growth in vitro and in vivo through suppressing ataxia telangiectasia and Rad3-related protein kinase

BackgroundEsophageal cancer has a global impact on human health due to its high incidence and mortality. Therefore, there is an urgent need to develop new drugs to treat or prevent the prominent pathological subtype of esophageal cancer, esophageal squamous cell carcinoma. Based upon a screening of drugs approved by the Food and Drug Administration, we discovered that Arbidol could effectively inhibit the proliferation of esophageal squamous cell carcinoma in vitro and in vivo. MethodWe first conducted a series of cell-based assays and found that Arbidol treatment inhibited the proliferation and colony formation ability of ESCC cells and promoted G1 phase cell cycle arrest. Phospho-proteomics experiments and in vitro kinase assays were subsequently performed using cell lysates derived from Arbidol-treated cells in order to identify the underlying growth inhibitory mechanism. Finally, a PDX model was used to verify the inhibitory effect of Arbidol in vivo. FindingArbidol inhibits proliferation of ESCC in vitro and in vivo through the DNA replication pathway and is associated with the cell cycle. InterpretationArbidol is a potential ATR inhibitor via binding to ATR kinase to reduce the phosphorylation and activation of MCM2 at Ser108. FundingThis research was supported by the National Natural Science Foundation of China (grant number 81872335), the National Natural Science Youth Foundation (grant number 81902486), and the Natural Science Foundation of Henan (grant number 161100510300).

cancer biology↗

Delineate clonal dynamics of ovarian cancer initiating cells during pre-malignant progression using a mouse genetic mosaic system

Different cellular compartments within a tissue present distinct cancer-initiating capacities. Current approaches to delineate cancer-initiating heterogeneity require a well-understood lineage hierarchy and cell-specific genetic tools, which are lacking for many tissues. Here, we circumvented this hurdle and investigated the capacity of fallopian tube cells in initiating serous ovarian cancer, utilizing a mouse genetic system that generates scattered GFP-labeled mutant cells. Through quantitative tracing of clonal expansion of individual mutant cells, we revealed that only a rare primitive subset enriched in the distal fallopian tube is capable of clonal expansion whereas others stall immediately upon acquiring oncogenic mutations. Expanded clones from this subset then encountered further attrition: many stalled shortly after while others sustained small cluster of proliferative cells and biased differentiation toward primitive fate. Taken together, our study showcases quantitative clonal tracing as a powerful approach to investigate cancer-initiating heterogeneity and clonal trajectory in tissues with limited prior knowledge.

cancer biology↗

A scalp geometry parameter-space for optimization and implementation of conventional TMS coil placement

Transcranial magnetic stimulation efficacy is largely dependent upon coil position and orientation. A good method for describing coil placement is required for both computational optimization (planning) and actual placement (implementation). In coordinate dependent parameter-spaces (CDPs), three-dimensional coordinates are used to represent coil position and three orthogonal unit vectors are used to represent coil orientation. A CDP can precisely describe arbitrary coil placement; therefore it offers great advantage in computational optimization which checks through all possible placements. However, a neuronavigation system is usually required to accurately implement the optimized CDP parameters on a participants head. Routine clinical practice, on the other hand, often uses the International 10-20 system to describe coil placement. Although the 10-20 system can only perform modeling and placement at limited scalp landmarks, it allows the synthesis of different individuals targeting effects to find group-optimal parameters; it also allows manual placement, which is important for commonly-seen use cases without individual MRI scans and navigation devices. This study proposes a new scalp geometry based parameter-space (SGP), integrating the advantages of CDP and 10-20 methods. Our SGP 1) can quantitatively specify all possible conventional coil positions and orientations on an individuals scalp, which is important for electrical modeling and optimization, 2) maintains inter-individual correspondence, which is important for synthesizing TMS effects from different individuals and studies. 3) enables fast and simple manual implementation. Demonstration experiments were conducted to illustrate the application of an SGP-based framework for both individual and group-based optimization. A measurement experiment was performed to evaluate speed, precision and reliability of SGP-based manual implementation; results show it surpasses previous manual placement methods.

neuroscience↗

Molecular basis for allosteric agonism and G protein subtype selectivity of galanin receptors

Peptide hormones and neuropeptides are complex signaling molecules that predominately function through G protein-coupled receptors (GPCRs). Two fundamental questions remained in the field of peptide-GPCR signaling systems are the basis for the diverse binding mode of peptide ligands and the specificity of G protein coupling. Here we report the structures of a neuropeptide, galanin, bound to its receptors, GAL1R and GAL2R, in complex with their primary G protein subtypes Gi and Gq, respectively. The structures reveal a unique binding pose of galanin, which almost lay flat on the top of the receptor transmembrane domain pocket in an -helical conformation, and acts as an allosteric-like agonist via a distinct signal transduction cascade. The structures also uncover the important features of intracellular loop 2 (ICL2) that mediate specific interactions with Gq, thus determining the selective coupling of Gq to GAL2R. ICL2 replacement in Gi-coupled GAL1R, OR, 5-HT1AR, and Gs-coupled b2AR and D1R with that of GAL2R promotes Gq coupling of these receptors, highlighting the dominant roles of ICL2 in Gq selectivity. Together our results provide important insights into peptide ligand recognition and allosteric activation of galanin receptors and uncover a general structural element for Gq coupling selectivity.

molecular biology↗

Topological supramolecular network enabled highly conductive and stretchable organic bioelectronics

Intrinsically stretchable bioelectronic devices based on soft and conducting organic materials have been regarded as the ideal interface for seamless and biocompatible integration with the human body. However, the grand challenge remains for the conducting polymer to possess both high mechanical ductility and good electrical conduction at cellular level feature sizes. This longstanding material limitation in organic bioelectronics has impeded the full exploitation of its unique benefits. Here, we introduce a new molecular engineering strategy based on rationally designed topological supramolecular networks, which allows effective decoupling of competing effects from multiple molecular building blocks to meet complex requirements. We achieve two orders of magnitude improvement in the conductivity under 100% strain in physiological environment, along with the capability for direct photopatterning down to 2 m. These unprecedented capabilities allow us to realize previously inaccessible bioelectronic applications including high-resolution monitoring of soft and malleable creatures, e.g., octopus, and localized neuromodulation down to single nucleus precision for controlling organ-specific activities through delicate tissues, e.g., brainstem.

bioengineering↗

Wireless closed-loop smart bandage for chronic wound management and accelerated tissue regeneration

Chronic non-healing wounds represent a major source of morbidity for patients and a significant economic burden. Current wound care treatments are generally passive and are unable to adapt to changes in the wound environment in real time. By integrating multimodal sensors and adding stimulators in a bandage, real-time physiological monitoring is possible and provides an opportunity for active intervention into the complex wound environment. Here, we develop a battery-free flexible bioelectronic system consisting of wirelessly powered, closed-loop sensing and stimulation circuits with tissue-interfacing tough conducting hydrogel electrodes for robust signal transduction, on-demand adhesion, and detachment. Using multiple pre-clinical models, we demonstrate the capability of our wound care system to continuously monitor skin impedance and temperature, to trigger directional electrical stimulation. The accelerated wound closure was confirmed to be due to the activation of pro-regenerative genes linked to accelerated wound closure, increased neovascularization, and enhanced dermal recovery.

bioengineering↗

A Saturated Map of Common Genetic Variants Associated with Human Height from 5.4 Million Individuals of Diverse Ancestries

Common SNPs are predicted to collectively explain 40-50% of phenotypic variation in human height, but identifying the specific variants and associated regions requires huge sample sizes. Here we show, using GWAS data from 5.4 million individuals of diverse ancestries, that 12,111 independent SNPs that are significantly associated with height account for nearly all of the common SNP-based heritability. These SNPs are clustered within 7,209 non-overlapping genomic segments with a median size of ~90 kb, covering ~21% of the genome. The density of independent associations varies across the genome and the regions of elevated density are enriched for biologically relevant genes. In out-of-sample estimation and prediction, the 12,111 SNPs account for 40% of phenotypic variance in European ancestry populations but only ~10%-20% in other ancestries. Effect sizes, associated regions, and gene prioritization are similar across ancestries, indicating that reduced prediction accuracy is likely explained by linkage disequilibrium and allele frequency differences within associated regions. Finally, we show that the relevant biological pathways are detectable with smaller sample sizes than needed to implicate causal genes and variants. Overall, this study, the largest GWAS to date, provides an unprecedented saturated map of specific genomic regions containing the vast majority of common height-associated variants.

genetics↗

Three amphioxus reference genomes reveal gene and chromosome evolution of chordates

The slow-evolving invertebrate amphioxus has an irreplaceable role in advancing our understanding into the vertebrate origin and innovations. Here we resolve the nearly complete chromosomal genomes of three amphioxus species, one of which best recapitulates the 17 chordate ancestor linkage groups. We reconstruct the fusions, retention or rearrangements between descendants of whole genome duplications (WGDs), which gave rise to the extant microchromosomes likely existed in the vertebrate ancestor. Similar to vertebrates, the amphioxus genome gradually establishes its 3D chromatin architecture at the onset of zygotic activation, and forms two topologically associated domains at the Hox gene cluster. We find that all three amphioxus species have ZW sex chromosomes with little sequence differentiation, and their putative sex-determining regions are nonhomologous to each other. Our results illuminate the unappreciated interspecific diversity and developmental dynamics of amphioxus genomes, and provide high-quality references for understanding the mechanisms of chordate functional genome evolution.

evolutionary biology↗

Genomic insights into the phylogeny and biomass-degrading enzymes of rumen ciliates

Understanding the biodiversity and genetics of the gut microbiome has important implications for host physiology. One underexplored and elusive group is ciliated protozoa, which play crucial roles in regulating gut microbial interactions. Integrating single-cell sequencing and an assembly-and-identification pipeline, we acquired 52 high-quality ciliate genomes of 22 rumen morphospecies for all major abundant clades. With these genomes, we firstly resolved the taxonomic and phylogenetic framework that reclassified them into 19 species spanning 13 genera and reassigned the genus Dasytricha from Isotrichidae to a new family Dasytrichidae. Via extensive horizontal gene transfer and gene family expansion, rumen ciliates possess a broad array of enzymes to synergistically degrade plant and microbial carbohydrates. In particular, [~]80% of the degrading enzymes in Diplodiniinae and Ophryoscolecinae act on plant cell wall, and the high activities of their cellulase, xylanase and lysozyme reflect the potential of ciliate enzymes for biomass-conversion. Additionally, the new ciliate dataset greatly facilitated the rumen metagenomic analyses by allowing [~]12% of reads to be classified.

microbiology↗

Structures of the Omicron Spike trimer with ACE2 and an anti-Omicron antibody

The Omicron variant of SARS-CoV-2 has rapidly become the dominant infective strain and the focus efforts against the ongoing COVID-19 pandemic. Here we report an extensive set of structures of the Omicron spike trimer by its own or in complex with ACE2 and an anti-Omicron antibody. These structures reveal that most Omicron mutations are located on the surface of the spike protein, which confer stronger ACE2 binding by nearly 10 folds but become inactive epitopes resistant to many therapeutic antibodies. Importantly, both RBD and the closed conformation of the Omicron spike trimer are thermodynamically unstable, with the melting temperature of the Omicron RBD decreased by as much as 7{degrees}C, making the spiker trimer prone to random open conformations. An unusual RBD-RBD interaction in the ACE2-spike complex unique to Omicron is observed to support the open conformation and ACE2 binding, serving the basis for the higher infectivity of Omicron. A broad-spectrum therapeutic antibody JMB2002, which has completed Phase 1 clinical trial, is found to interact with the same two RBDs to inhibit ACE2 binding, in a mode that is distinguished from all previous antibodies, thus providing the structural basis for the potent inhibition of Omicron by this antibody. Together with biochemical data, our structures provide crucial insights into higher infectivity, antibody evasion and inhibition of Omicron.

biophysics↗