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Li, J.-Y.

Publications and source records attributed to Li, J.-Y..

15 recordsLinked to original sources

Corallimorpharian genome supports the monophyly of Scleractinia and illuminates the cellular evolution of coral calcification

The production of calcified skeletons by stony corals is the cornerstone of reef ecosystems and the persistence of marine biodiversity. Corallimorpharians, sometimes described as naked corals, resemble stony corals in many respects but lack hardened skeletons. However, whether they are stony corals that secondarily lost their skeletons has been a subject of much debate. Here, we present a chromosome-level genome of the corallimorpharian Ricordea yuma and show that macrosynteny and microsynteny analyses provide strong support for corallimorpharians as the sister group to stony corals. This phylogenetic placement indicates that corallimorpharians were not ancestrally skeletonized and therefore occupy a critical outgroup position for reconstructing the origin of coral calcification. Guided by this phylogenetic context, we sequenced whole-polyp single-cell transcriptomes from R. yuma and the complex coral Galaxea fascicularis and found that the scleractinian skeleton evolved through the emergence of a derived calicoblast cell state in stony corals. A combination of comparative genomics and regeneration experiments in G. fascicularis show that the emergence of the calicoblast cell state was accompanied by the evolution of a biomineralization toolkit assembled from lineage-specific innovations and co-opted ancestral components. Although corallimorpharians retain some ancestral genes later incorporated into coral biomineralization, they lack a detectable calicoblast-like transcriptional state and many core calcification genes. Together, our findings indicate that coral calcification arose through coordinated changes in genome architecture, gene repertoire, and cell identity, highlighting this process as a major evolutionary transition driven by the integration of genomic and cellular innovations.

evolutionary biology↗

A systematic delineation of 3'UTR regulatory elements and their contextual associations

The 3'UTR encodes regulatory information that shapes transcript abundance and subcellular distribution, yet the underlying sequence rules remain incompletely defined. Using SEERS, we quantified the effects of [~]2 million synthetic 3'UTR inserts in A549 and HCT116 cells on RNA output and nuclear-cytoplasmic partitioning. We identify a broad repertoire of short (2[~]8 nt) elements whose effects largely align along a major coupled axis that links high expression with cytoplasmic enrichment and low expression with nuclear enrichment, and contribute predominantly in an additive manner. A context-aware deep learning model (TALE) captures most of this behavior while revealing that strong context dependence is uncommon and emerges mainly in rare, extreme contexts consistent with higher-order constraints. Applying TALE to ClinVar 3'UTR variants prioritizes a subset of pathogenic SNVs with aberrant predicted effects, frequently explained by creation or disruption of splice-site-like U1 telescripting signals, highlighting a potent route to 3'UTR-driven disease mechanisms.

genomics↗

Dissecting the differential role of C-terminal truncations in the regulation of aSyn pathology formation and the biogenesis of Lewy bodies

Alpha-synuclein (aSyn) post-translational modifications (PTMs), particularly phosphorylation at serine 129 and C-terminal truncations, are highly enriched in Lewy bodies (LBs), Lewy neurites, and other types of aSyn pathological aggregates in the brain of patients with Parkinsons disease (PD) and other synucleinopathies. However, our knowledge about the precise role of PTMs in regulating the different stages of pathology formation, neurodegeneration, and aSyn pathology spreading remains incomplete. In this work, we applied a systematic approach to address this knowledge gap with an emphasis on mapping and elucidating the role of post-fibrillization C-terminal aSyn truncations in regulating the uptake, processing, seeding activity, and formation of LB-like inclusions and maturations in a well-established neuronal seeding model that recapitulates all the stages leading to LB formation and neurodegeneration. Our work shows that C-terminal cleavage of aSyn fibrils at multiple sites is a conserved process that occurs rapidly after and during the formation of intracellular LB-like aSyn inclusions in all neuronal seeding models. Interestingly, blocking the cleavage of internalized fibrils does not influence their seeding activity, whereas inhibiting the enzymes that regulate the cleavage of newly formed fibrils (e.g., calpains 1 and 2) significantly alters the formation of LB-like inclusions. We also show that C-terminal truncations, in combination with other PTMs, play a crucial role in regulating the interactome and remodeling of newly formed aSyn fibrils, including their shortening, lateral association, and packing during LB formation and maturation. Altogether, our results demonstrate that post-fibrillization C-terminal truncations have a differential role at different stages of aSyn aggregation and pathology formation. These insights, combined with the abundance of truncated aSyn species in LBs, have significant implications in understanding aSyn pathological diversity and developing therapeutic strategies targeting the C-terminus of aSyn or its proteolytic processing.

neuroscience↗

Aromatase-independent estrogenesis: Wood-Ljungdahl pathway likely contributed to the emergence of estrogens in the biosphere

Androgen and estrogen, key sex hormones, were long thought to be exclusively produced by vertebrates. The O2-dependent aromatase that converts androgen to estrogen (estrogenesis) has never been identified in any prokaryotes. Here, we report the discovery of anaerobic estrogenesis in a Peptococcaceae bacterium (strain TUW77) isolated from the gut of the great blue-spotted mudskipper (Boleophthalmus pectinirostris). This strain exhibits unprecedented testosterone fermentation pathways, transforming testosterone into estrogens and androstanediol under anaerobic conditions. Physiological experiments revealed that strain TUW77 grows exclusively on testosterone, utilizing the androgenic C-19 methyl group as both the carbon source and electron donor. The genomic analysis identified three copies of a polycistronic gene cluster, abeABC (anaerobic bacterial estrogenesis), encoding components of a classic cobalamin-dependent methyltransferase system. These genes, highly expressed under testosterone-fed conditions, show up to 57% protein identity to the characterized EmtAB from denitrifying Denitratisoma spp., known for methylating estrogen into androgen (the reverse reaction). Tiered transcriptomic and proteomic analyses suggest that the removed C-19 methyl group is completely oxidized to CO2 via the oxidative Wood-Ljungdahl pathway, while the reducing equivalents (NADH) fully reduce remaining testosterone to androstanediol. Consistently, the addition of anthraquinone-2,6-disulfonate, an extracellular electron acceptor, to testosterone-fed TUW77 cultures enabled complete testosterone conversion into estrogen without androstanediol accumulation (anaerobic testosterone oxidation). This discovery of aromatase-independent estrogenesis in anaerobic bacteria suggests that the ancient Wood-Ljungdahl pathway may have contributed to the emergence of estrogens in the early biosphere. SignificanceUsing a testosterone-grown anaerobic bacterium as a model organism, we characterized this unusual anaerobic estrogenesis at the molecular level. Our findings challenge the long-held belief that estrogen production is exclusive to aromatase-containing vertebrates, expanding our understanding of steroid hormone biosynthesis across domains of life. The involvement of ancient strictly anaerobic Peptococcaceae members and the Wood-Ljungdahl pathway suggests that bacterial estrogenesis may predate O2-dependent estrogenesis in vertebrates. Furthermore, the identification of estrogen-producing bacteria in animal guts opens new avenues for potential microbiome-based hypoestrogenism therapies to supplement estrogen in menopausal or ovariectomized females, offering an innovative alternative to current hormone replacement strategies.

microbiology↗

Markonv: a novel convolutional layer with inter-positional correlations modeled

Deep neural networks equipped with convolutional neural layers have been widely used in omics data analysis. Though highly efficient in data-oriented feature detection, the classical convolutional layer is designed with inter-positional independent filters, hardly modeling inter-positional correlations in various biological data. Here, we proposed Markonv layer (Markov convolutional neural layer), a novel convolutional neural layer with Markov transition matrices as its filters, to model the intrinsic dependence in inputs as Markov processes. Extensive evaluations based on both synthetic and real-world data showed that Markonv-based networks could not only identify functional motifs with inter-positional correlations in large-scale omics sequence data effectively, but also decode complex electrical signals generated by Oxford Nanopore sequencing efficiently. Designed as a drop-in replacement of the classical convolutional layer, Markonv layers enable an effective and efficient identification for inter-positional correlations from various biological data of different modalities. All source codes of a PyTorch-based implementation are publicly available on GitHub for academic usage.

bioinformatics↗

Key mutations on spike protein altering ACE2 receptor utilization and potentially expanding host range of emerging SARS-CoV-2 variants

Increasing evidence supports inter-species transmission of SARS-CoV-2 variants from human to domestic or wild animals during the ongoing COVID-19 pandemic, which is posing great challenges to epidemic control. Clarifying the host range of emerging SARS-CoV-2 variants will provide instructive information for the containment of viral spillover. The spike protein (S) of SARS-CoV-2 is the key determinant of receptor utilization, and therefore amino acid mutations on S will probably alter viral host range. Here, in order to evaluate the impact of S mutations, we constructed 20 Hela cell lines stably expressing ACE2 orthologs from different animals, and prepared 27 pseudotyped SARS-CoV-2 carrying different spike mutants, among which 20 bear single mutation and the other 7 were cloned from emerging SARS-CoV-2 variants, including D614G, Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Delta (B.1.135), Lambda (B.1.429) and Mu (B.1.525). Using pseudoviral reporter assay, we identified that the substitutions of T478I and N501Y enabled the pseudovirus to utilize chicken ACE2, indicating potential infectivity to avian species. Furthermore, the S mutants of real SARS-CoV-2 variants comprising N501Y showed significantly acquired abilities to infect cells expressing mouse ACE2, indicating a critical role of N501Y in expanding SARS-CoV-2 host range. In addition, A262S and T478I significantly enhanced the utilization of various mammals ACE2. In summary, our results indicated that T478I and N501Y substitutions were two S mutations important for receptor adaption of SARS-CoV-2, potentially contributing to spillover of the virus to many other animal hosts. Therefore, more attention should be paid to SARS-CoV-2 variants with these two mutations.

microbiology↗

Aβ/APP-induced hyperexcitability and dysregulation of homeostatic synaptic plasticity in models of Alzheimer's disease

The proper function of the nervous system is dependent on the appropriate timing of neuronal firing. Synapses continually undergo rapid activity-dependent modifications that require feedback mechanisms to maintain network activity within a window in which communication is energy efficient and meaningful. Homeostatic synaptic plasticity (HSP) and homeostatic intrinsic plasticity (HIP) are such negative feedback mechanisms. Accumulating evidence implicates that Alzheimers disease (AD)-related amyloid precursor protein (APP) and its cleavage product amyloid-beta (A{beta}) play a role in the regulation of neuronal network activity, and in particular HSP. AD features impaired neuronal activity with regional early hyper-activity and A{beta}-dependent hyperexcitability has also been demonstrated in AD transgenic mice. We demonstrate similar hyper-activity in AD transgenic neurons in culture that have elevated levels of both human APP and A{beta}. To examine the individual roles of APP and A{beta} in promoting hyperexcitability we used an APP construct that does not generate A{beta}, or elevated A{beta} levels independently of APP. Increasing either APP or A{beta} in wild type (WT) neurons leads to increased frequency and amplitude of calcium transients. Since HSP/HIP mechanisms normally maintain a setpoint of activity, we examined whether homeostatic synaptic/intrinsic plasticity was altered in AD transgenic neurons. Using methods known to induce HSP/HIP, we demonstrate that APP protein levels are regulated by chronic modulation of activity and show that AD transgenic neurons have an impaired response to global changes in activity. Further, AD transgenic compared to WT neurons failed to adjust the length of their axon initial segments (AIS), an adaptation known to alter excitability. Thus, we present evidence that both APP and A{beta} influence neuronal activity and that mechanisms of HSP/HIP are disrupted in neuronal models of AD.

neuroscience↗

Quantitative model suggests both intrinsic and contextual features contribute to the transcript coding ability determination in cells

Gene transcription and protein translation are two key steps of the "central dogma". It is still a major challenge to quantitatively deconvolute factors contributing to the coding ability of transcripts in mammals. Here, we propose Ribosome Calculator (RiboCalc) for quantitatively modeling the coding ability of RNAs in human genome. In addition to effectively predicting the experimentally confirmed coding abundance via sequence and transcription features with high accuracy, RiboCalc provides interpretable parameters with biological information. Large-scale analysis further revealed a number of transcripts with a variety of coding ability for distinct types of cells (i.e., context-dependent coding transcripts, CDCTs), suggesting that, contrary to conventional wisdom, a transcripts coding ability should be modeled as a continuous spectrum with a context-dependent nature.

bioinformatics↗

Genomic evidence for divergent co-infections of SARS-CoV-2 lineages

Recently, patients co-infected by two SARS-CoV-2 lineages have been sporadically reported. Concerns are raised because previous studies have demonstrated co-infection may contribute to the recombination of RNA viruses and cause severe clinic symptoms. In this study, we have estimated the compositional lineage(s), tendentiousness, and frequency of co-infection events in population from a large-scale genomic analysis for SARS-CoV-2 patients. SARS-CoV-2 lineage(s) infected in each sample have been recognized from the assignment of within-host site variations into lineage-defined feature variations by introducing a hypergeometric distribution method. Of all the 29,993 samples, 53 (~0.18%) co-infection events have been identified. Apart from 52 co-infections with two SARS-CoV-2 lineages, one sample with co-infections of three SARS-CoV-2 lineages was firstly identified. As expected, the co-infection events mainly happened in the regions where have co-existed more than two dominant SARS-CoV-2 lineages. However, co-infection of two sub-lineages in Delta lineage were detected as well. Our results provide a useful reference framework for the high throughput detecting of SARS-CoV-2 co-infection events in the Next Generation Sequencing (NGS) data. Although low in average rate, the co-infection events showed an increasing tendency with the increased diversity of SARS-CoV-2. And considering the large base of SARS-CoV-2 infections globally, co-infected patients would be a nonnegligible population. Thus, more clinical research is urgently needed on these patients.

microbiology↗

The bacterial amyloids phenol soluble modulins from Staphylococcus aureus catalyze alpha-synuclein aggregation

Aggregated -synuclein (-syn) is the main constituent of Lewy bodies, the main pathological hallmark of Parkinsons disease (PD). Environmental factors are thought to be potential triggers capable of initiating the aggregation of the otherwise monomeric -syn. Braaks seminal work redirected attention to the intestine and recent reports of dysbiosis have highlighted the potential causative role that the microbiome might play in the pathology of PD. Staphylococcus aureus is a bacterium carried by 30-70% of the general population. It has been shown to produce functional amyloids, called Phenol Soluble Modulins (PSMs). Here, we studied the kinetics of -syn aggregation under quiescent conditions in the presence or absence of four different PSM peptides and observed a remarkable shortening of the lag phase in their presence. Whereas pure -syn monomer did not aggregate up to 450 h after initiation of the experiment in neither neutral nor mildly acidic buffer, the addition of different PSM peptides resulted in an almost immediate increase in the Thioflavin T (ThT) fluorescence. Despite similar peptide sequences, the different PSM peptides displayed distinct effects on the kinetics of -syn aggregation. Kinetic analyses of the data suggest that while all four peptides catalyze -syn aggregation, the underlying mechanisms might differ with a model of nucleation and elongation fitting the -syn aggregation induced by PSM2 but not PSM1. The results of immunogold TEM imply that the aggregates are fibrillar and composed of -syn. Addition of the co-aggregated materials to HEK cells expressing the A53T -syn variant fused to GFP was found to catalyze -syn aggregation and phosphorylation in the cells. Our results provide evidence of a potential trigger of synucleinopathies and could have implications for the prevention of the diseases.

biochemistry↗

FRET-based screening in HEK293T identifies p38 MAPK and PKC inhibition as therapeutic targets for α-synuclein aggregation

Aggregation of -synuclein is associated with neurodegeneration and a hallmark pathology in synucleinopathies. These aggregates are thought to function as prion-like particles where the conformation of misfolded -synuclein determines the induced pathologys traits similar to prion diseases. Still, little is known about the molecular targets facilitating the conformation-specific biological effects, but their identification could form the basis for new therapeutic intervention. High-throughput screening (HTS) of annotated compound libraries could facilitate mechanistic investigation by identifying targets with impact on -synuclein aggregation. To this end, we developed a FRET-based cellular reporter in HEK293T cells, with sensitivity down to 6.5 nM -synuclein seeds. Using this model system, we identified GF109203X, SB202190, and SB203580 as inhibitors capable of preventing induction of - synuclein aggregation via inhibition of p38 MAPK and PKC, respectively. Our findings highlight the value HTS brings to the mechanistic investigation of -synuclein aggregation while simultaneously identifying novel therapeutic compounds.

molecular biology↗

Receptor utilization of angiotensin converting enzyme 2 (ACE2) indicates a narrower host range of SARS-CoV-2 than that of SARS-CoV

Coronavirus pandemics have become a huge threat to the public health worldwide in the recent decades. Typically, SARS-CoV caused SARS pandemic in 2003 and SARS-CoV-2 caused the COVID-19 pandemic recently. Both viruses have been reported to originate from bats. Thus, direct or indirect interspecies transmission from bats to humans is required for the viruses to cause pandemics. Receptor utilization is a key factor determining the host range of viruses which is critical to the interspecies transmission. Angiotensin converting enzyme 2 (ACE2) is the receptor of both SARS-CoV and SARS-CoV-2, but only ACE2s of certain animals can be utilized by the viruses. Here, we employed pseudovirus cell-entry assay to evaluate the receptor-utilizing capability of ACE2s of 20 animals by the two viruses and found that SARS-CoV-2 utilized less ACE2s than SARS-CoV, indicating a narrower host range of SARS-CoV-2. Meanwhile, pangolin CoV, another SARS-related coronavirus highly homologous to SARS-CoV-2 in its genome, yet showed similar ACE2 utilization profile with SARS-CoV rather than SARS-CoV-2. To clarify the mechanism underlying the receptor utilization, we compared the amino acid sequences of the 20 ACE2s and found 5 amino acid residues potentially critical for ACE2 utilization, including the N-terminal 20th and 42nd amino acids that may determine the different receptor utilization of SARS-CoV, SARS-CoV-2 and pangolin CoV. Our studies promote the understanding of receptor utilization of pandemic coronaviruses, potentially contributing to the virus tracing, intermediate host screening and epidemic prevention for pathogenic coronaviruses.

microbiology↗

Mycena genomes resolve the evolution of fungal bioluminescence

Mushroom-forming fungi in the order Agaricales represent an independent origin of bioluminescence in the tree of life, yet the diversity, evolutionary history, and timing of the origin of fungal luciferases remain elusive. We sequenced the genomes and transcriptomes of five bonnet mushroom species (Mycena spp.), a diverse lineage comprising the majority of bioluminescent fungi. Two species with haploid genome assemblies [~]150Mb are amongst the largest in Agaricales, and we found that a variety of repeats between Mycena species were differentially mediated by DNA methylation. We show that bioluminescence evolved in the last common ancestor of mycenoid and the marasmioid clade of Agaricales and was maintained through at least 160 million years of evolution. Analyses of synteny across genomes of bioluminescent species resolved how the luciferase cluster was derived by duplication and translocation, frequently rearranged and lost in most Mycena species, but conserved in the Armillaria lineage. Luciferase cluster members were co-expressed across developmental stages, with highest expression in fruiting body caps and stipes, suggesting fruiting-related adaptive functions. Our results contribute to understanding a de novo origin of bioluminescence and the corresponding gene cluster in a diverse group of enigmatic fungal species. SignificanceWe present the genomes of five new bonnet mushroom Mycena species, formerly the last fungal bioluminescent lineage lacking reference genomes. These genome-scale datasets allowed us to construct an evolutionary model pinpointing all possible changes in the luciferase cluster across all fungi and additional genes involved in bioluminescence. We show that luciferase clusters were differentially lost in different fungal lineages and in particular a substantial loss was observed in the Mycena lineage. This can be attributed to genome regions of Mycena underwent different evolutionary dynamics. Our findings offer insights into the evolution of how a gene cluster that emerged 160 million years ago and was frequently lost or maintained due to differences in genome plasticity.

genomics↗

Low-protein/high-carbohydrate diet induces AMPK-dependent canonical and non-canonical thermogenic response in subcutaneous adipose tissue

Low-protein/high-carbohydrate (LPHC) diet promotes metabolic health and longevity in adult humans and animal models. However, the complex molecular underpinnings of how LPHC diet leads to metabolic benefits remain elusive. Through a multi-layered approach, here we observed that LPHC diet promotes an energy-dissipating response consisting in the parallel recruitment of canonical and non-canonical (muscular) thermogenic systems in subcutaneous white adipose tissue (sWAT). In particular, we measured Ucp1 induction in association with up-regulation of actomyosin components and several Serca (Serca1, Serca2a, Serca2b) ATPases. In beige adipocytes, we observed that AMPK activation is responsible for transducing the amino acid lowering in an enhanced fat catabolism, which sustains both Ucp1- and Serca-dependent energy dissipation. Limiting AMPK activation counteracts the expression of brown fat and muscular genes, including Ucp1 and Serca, as well as mitochondrial oxidative genes. We observed that mitochondrial reactive oxygen species are the upstream molecules controlling AMPK-mediated metabolic rewiring in amino acid-restricted beige adipocytes. Our findings delineate a novel metabolic phenotype of responses to amino acid shortage, which recapitulates some of the benefits of cool temperature in sWAT. In conclusion, this highlights LPHC diet as a valuable and practicable strategy to prevent metabolic diseases through the enhancement of mitochondrial oxidative metabolism and the recruitment of different energy dissipating routes in beige adipocytes.

physiology↗

Integrative model to coordinate the oligomerization and aggregation mechanisms of CCL5

The CC-type chemokine ligand 5 (CCL5) is involved in the pathogenesis of many inflammatory conditions. The oligomerization and aggregation of CCL5 are considered to be responsible for its inflammatory properties. The CC-type dimer acts as the basic unit to constitute the oligomer. However, the structural basis of CCL5 oligomerization remains controversial. In this study, NMR and biophysical analyses proposed evidence that no single dimer-dimer interaction dominates in the oligomerization process of CCL5. CCL5 could oligomerize alternatively through two different interactions, E66-K25 and E66-R44/K45. In addition, a newly determined trimer structure reported an interfacial interaction through the N-terminal 12FAY14 sequence. The interaction contributes to aggregation and precipitation. In accordance with the observations, an integrative model explains the CCL5 oligomerization and aggregation process. CCL5 assembly consists of two types of dimer-dimer interactions and one aggregation mechanism. For full-length CCL5, the molecular accumulation triggers oligomerization through the E66-K25 interaction, and the 12FAY14 interaction acts as a secondary effect to derive aggregation. The E66-R44/K45 interaction dominates in CCL5 N-terminal truncations. The interaction would lead to filament-like formation in solution.

biochemistry↗