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Biology subjects

Cao, Y.

Publications and source records attributed to Cao, Y..

At least 307 records · Page 17Linked to original sources

Combinatorial engineering of bulk-assembled monodisperse coacervate droplets towards logically integrated protocells

Bottom-up synthetic biology seeks to construct artificial cells from simple building blocks for exploring origin and principles of cellular life and material design. Although cellular life may have emerged spontaneously, programmable integration of building blocks into size, membrane property-controlled compartments (liposome or coacervate) towards cellular organization, without using specialized devices, has proven difficult. Here, we report a self-templated route to monodisperse complex droplets in bulk solution from coacervate-liposome synergy, with nanoliposome controlling coacervate size and coacervate templating on-surface nanoliposome fusion. Nanoliposome-coated monodisperse coacervates are self-assembled within 30 seconds, which are sealed by fusing nanoliposomes into size-controlled giant unilamellar vesicles (GUVs), with model building blocks combinatorially integrated into droplets. Defect-free membrane is established on coacervate, which render these complex GUVs surviving at extreme osmotic, salty and pH conditions (4 M NaCl, 100 mM HCl, 1 M NaOH), while providing homeostasis for enzymatic reactions, reminiscent of extremophiles.

synthetic biology↗

Intrinsic bias at non-canonical, β-arrestin-coupled seven transmembrane receptors

G protein-coupled receptors (GPCRs) are typically characterized by their seven transmembrane (7TM) architecture, and interaction with two universal signal-transducers namely, the heterotrimeric G-proteins and {beta}-arrestins ({beta}arrs). Synthetic ligands and receptor mutants have been designed to elicit transducer-coupling preferences and distinct downstream signaling outcomes for many GPCRs. This raises the question if some naturally-occurring 7TMRs may selectively engage one of these two signal-transducers, even in response to their endogenous agonists. Although there are scattered hints in the literature that some 7TMRs lack G-protein coupling but interact with {beta}arrs, an in-depth understanding of their transducer-coupling preference, GRK-engagement, downstream signaling and structural mechanism remains elusive. Here, we use an array of cellular, biochemical and structural approaches to comprehensively characterize two non-canonical 7TMRs namely, the human decoy D6 receptor (D6R) and the human complement C5a receptor (C5aR2), in parallel with their canonical GPCR counterparts, CCR2 and C5aR1, respectively. We discover that D6R and C5aR2 couple exclusively to {beta}arrs, exhibit distinct GRK-preference, and activate non-canonical downstream signaling partners. We also observe that {beta}arrs, in complex with these receptors, adopt distinct conformations compared to their canonical GPCR counterparts despite being activated by a common natural agonist. Our study therefore establishes D6R and C5aR2 as bona-fide arrestin-coupled receptors (ACRs), and provides important insights into their regulation by GRKs and downstream signaling with direct implications for biased agonism.

biochemistry↗

SAILER: Scalable and Accurate Invariant Representation Learning for Single-Cell ATAC-Seq Processing and Integration

MotivationSingle-cell sequencing assay for transposase-accessible chromatin (scATAC-seq) provides new opportunities to dissect epigenomic heterogeneity and elucidate transcriptional regulatory mechanisms. However, computational modelling of scATAC-seq data is challenging due to its high dimension, extreme sparsity, complex dependencies, and high sensitivity to confounding factors from various sources. ResultsHere we propose a new deep generative model framework, named SAILER, for analysing scATAC-seq data. SAILER aims to learn a low-dimensional nonlinear latent representation of each cell that defines its intrinsic chromatin state, invariant to extrinsic confounding factors like read depth and batch effects. SAILER adopts the conventional encoder-decoder framework to learn the latent representation but imposes additional constraints to ensure the independence of the learned representations from the confounding factors. Experimental results on both simulated and real scATAC-seq datasets demonstrate that SAILER learns better and biologically more meaningful representations of cells than other methods. Its noise-free cell embeddings bring in significant benefits in downstream analyses: Clustering and imputation based on SAILER result in 6.9% and 18.5% improvements over existing methods, respectively. Moreover, because no matrix factorization is involved, SAILER can easily scale to process millions of cells. We implemented SAILER into a software package, freely available to all for large-scale scATAC-seq data analysis. AvailabilityThe software is publicly available at https://github.com/uci-cbcl/SAILER Contactjingz31@uci.edu and xhx@uci.edu

bioinformatics↗

The fitness costs and benefits of trisomy of each Candida albicanschromosome

Candida albicans is a prevalent human fungal pathogen. Rapid genomic change, due to aneuploidy, is a common mechanism that facilitates survival from multiple types of stresses including the few classes of available antifungal drugs. The stress survival of aneuploids occurs despite the fitness costs attributed to most aneuploids growing under idealized lab conditions. Systematic study of the aneuploid state in C. albicans has been hindered by the lack of a comprehensive collection of aneuploid strains. Here, we describe a collection of diploid C. albicans aneuploid strains, each carrying one extra copy of each chromosome, all from the same genetic background. We tested the fitness of this collection under several physiological conditions including shifts in pH, low glucose, oxidative stress, temperature, high osmolarity, membrane stress and cell wall stress. We found that, most aneuploids, under most conditions, were less fit than their euploid parent, yet there were specific conditions under which specific aneuploid isolates provided a fitness benefit relative to the euploid parent strain. Importantly, this fitness benefit was attributable to the change in the copy number of specific chromosomes. Thus, C. albicans can tolerate aneuploidy of each chromosome and some aneuploids confer improved growth under conditions that the yeast encounters in its host niches.

genetics↗

Comprehensive comparison of transcriptomes in SARS-CoV-2 infection: alternative entry routes and innate immune responses

The pathogenesis of COVID-19 emerges as complex, with multiple factors leading to injury of different organs. Several studies on underlying cellular processes have produced contradictory claims, e.g. on SARS-CoV-2 cell entry or innate immune responses. However, clarity in these matters is imperative for therapy development. We therefore performed a meta-study with a diverse set of transcriptomes under infections with SARS-CoV-2, SARS-CoV and MERS-CoV, including data from different cells and COVID-19 patients. Using these data, we investigated viral entry routes and innate immune responses. First, our analyses support the existence of cell entry mechanisms for SARS and SARS-CoV-2 other than the ACE2 route with evidence of inefficient infection of cells without expression of ACE2; expression of TMPRSS2/TPMRSS4 is unnecessary for efficient SARS-CoV-2 infection with evidence of efficient infection of A549 cells transduced with a vector expressing human ACE2. Second, we find that innate immune responses in terms of interferons and interferon simulated genes are strong in relevant cells, for example Calu3 cells, but vary markedly with cell type, virus dose, and virus type.

bioinformatics↗

Pulmonary stromal expansion and intra-alveolar coagulation are primary causes of Covid-19 death

Most Covid-19 victims are old and die from unrelated causes. Here we present twelve complete autopsies, including two rapid autopsies of young patients where the cause of death was Covid-19 ARDS. The main virus induced pathology was in the lung parenchyma and not in the airways. Most coagulation events occurred in the intra-alveolar and not in the intra-vascular space and the few thrombi were mainly composed of aggregated thrombocytes. The dominant inflammatory response was the massive accumulation of CD163+ macrophages and the disappearance of T killer, NK and B-cells. The virus was replicating in the pneumocytes and macrophages but not in bronchial epithelium, endothel, pericytes or stromal cells. The lung consolidations were produced by a massive regenerative response, stromal and epithelial proliferation and neovascularization. We suggest that thrombocyte aggregation inhibition, angiogenesis inhibition and general proliferation inhibition may have a roll in the treatment of advanced Covid-19 ARDS.

pathology↗

A small increase in CHEK1 activity leads to the arrest of the first zygotic division in human

The first mitotic division in mammalian zygotes is unique. The fertilized egg reactivates its cell cycle, and the maternal and paternal genomes start to reprogram to become totipotent. The first division is very sensitive to a range of perturbations, particularly the DNA damage, leading to the embryo's failure to enter the first mitosis. We discovered that a point mutation in the human CHEK1 gene resulted in an Arginine 442 to Glutamine change at the C-terminus of the CHEK1 protein. CHEK1 R442Q mutation caused the zygote to arrest just before the first division. Heterozygote individuals appeared to be healthy except that the female carriers are infertile. Expressing the corresponding mouse mutant Chk1 protein in zygotes also caused arrest before the first mitosis. Treating Chk1 R442Q mouse zygotes with low concentrations of CHEK1 inhibitor enabled the embryos to overcome the cell cycle arrest and resume normal development. Our results revealed an unexpected zygote mitotic checkpoint, which is extremely sensitive to the CHEK1 kinase activity. The fine-tuning of the DNA damage checkpoint permits the arrested one-cell embryos to overcome the first mitotic block and develop into healthy animals. These findings have important implications in assisted human reproduction.

developmental biology↗

Coordinated regulation of ribosomes and proteasomes by PRMT1 in the maintenance of neural stemness of cancer cells and neural stem cells

Our studies suggest that neural stemness contributes to cell tumorigenicity. The basic cell physiological machineries and developmental programs, such as cell cycle, ribosomes, proteasomes, epigenetic factors, etc., which are upregulated in and promote cancers, are enriched in embryonic neural cells. How these machineries are coordinated is unknown. Here, we show that loss of neural stemness in cancer cells or neural stem cells leads to simultaneous downregulation of components of ribosomes and proteasomes, which are responsible for protein synthesis and degradation, respectively, and downregulation of major epigenetic factors. Inhibition of PRMT1 causes neuron-like differentiation, downregulation of a similar set of proteins, and alteration of subcellular localization of ribosome and proteasome components. PRMT1 interacts with these components, catalyzes arginine methylation of them and protects them from degradation, thereby maintaining a high level of expression of epigenetic factors that maintain neural stemness. PRMT1 inhibition results in repression of cell tumorigenicity. Therefore, PRMT1 coordinates ribosomes and proteasomes to match the needs for high protein production and protein homeostasis in cells with fast cell cycle and proliferation.

cell biology↗

High throughput functional screening for next generation cancer immunotherapy using droplet-based microfluidics

Currently high throughput approaches are lagged for isolation of antibodies whose function goes beyond simple binding, which have prevented the next generation cancer immunotherapeutics, such as bispecific T cell engager antibodies or agonist antibody of costimulatory receptor, from reaching their full potential. Here we developed a highly efficient droplet-based microfluidics platform combining with lentivirus transduction system that enables functional screening of millions of antibodies. To showcase the capacity of the system, functional antibodies for CD40 agonism with low frequency (<0.02%) were identified with 2 rounds of screening. To demonstrate its versatility, an anti-Her2/anti-CD3 bispecific antibody library was established using bispecific T cell Engager (BiTE) platform and functional screening enabled efficient identification of potent anti-Her2/anti-CD3 BiTE antibodies. The platform could revolutionize the next generation cancer immunotherapy drug development and research world.

cancer biology↗

LncRNA H19X is required for placenta development and angiogenesis through regulating a noncoding RNA regulatory network

H19X is a lncRNA specifically expressed in the placenta, whose expression is induced by hypoxia. H19X overexpression promoted trophoblast proliferation and invasion, while its knockdown or knockout inhibited trophoblast proliferation and invasion. Mechanistically, we demonstrated that reciprocal regulation exists with miR-424/miR-503 in the control of genes related to placental development and angiogenesis, including VEGF and VEGFR2. H19X inhibited ubiquitination of PIWIL1, thereby maintaining its stability and homeostatic expression of piRNAs. PIWIL1 overexpression rescued the defects of cell behavior caused by H19X KO. H19X deletion led to compromised HIF-1A/HIF-2A expression, which was correlated with the dysregulation of downstream genes under hypoxic conditions. CRISPR/Cas-9 knockout of H19X in animals led to defective placenta differentiation and compromised embryo development under hypoxic conditions. Western blotting showed reduced expression levels of PIWIL1 as well as angiogenesis marker genes, including VEGF and VEGFR2, in H19X KO mice. Thus, this study provides evidence of an unexpected link among lncRNA, miRNA, PIWIL1-related piRNA, and angiogenesis in placentation, the dysregulation of which leads to poor placental development and embryo loss under hypoxic conditions.

developmental biology↗

Epigenetic mechanisms mediating cell state transitions in chondrocytes.

Epigenetic modifications play critical roles in regulating cell lineage differentiation, but the epigenetic mechanisms guiding specific differentiation steps within a cell lineage have rarely been investigated. To decipher such mechanisms, we used the defined transition from proliferating (PC) into hypertrophic chondrocytes (HC) during endochondral ossification as a model. We established a map of activating and repressive histone modifications for each cell type. ChromHMM state transition analysis and Pareto-based integration of differential levels of mRNA and epigenetic marks revealed that differentiation associated gene repression is initiated by the addition of H3K27me3 to promoters still carrying substantial levels of activating marks. Moreover, the integrative analysis identified genes specifically expressed in cells undergoing the transition into hypertrophy. Investigation of enhancer profiles detected surprising differences in enhancer number, location, and transcription factor binding sites between the two closely related cell types. Furthermore, cell type-specific upregulation of gene expression was associated with a shift from low to high H3K27ac decoration. Pathway analysis identified PC-specific enhancers associated with chondrogenic genes, while HC-specific enhancers mainly control metabolic pathways linking epigenetic signature to biological functions.

developmental biology↗

Mammalian-unique eIF4E2 maintains GSK3β proline kinase activity to resist senescence against hypoxia

Cellular senescence is a stable state of cell cycle arrest elicited by various stresses. Hypoxia modulates senescence, but its consequences and implications in living organisms remains unknown. Here we identified the eIF4E2-GSK3{beta} pathway regulated by hypoxia to maintain p53 proline-directed phosphorylation (S/T-P) to prevent senescence. We previously knew that GSK3{beta} activates p53 translation through phosphorylation of RBM38 Ser195 (-Pro196). Unexpectedly, eIF4E2 directly binds to GSK3{beta} via a conserved motif, mediating Ser195 phosphorylation. Phosphoproteomics revealed that eIF4E2-GSK3{beta} specifically regulates proline-directed phosphorylation. Peptide e2-I or G3-I that disrupts this pathway dephosphorylates p53 at multiple S/T-P, which accelerate senescence by transcriptional suppressing TOPBP1 and TRX1. Consistently, peptides induce liver senescence that is rescued by TOPBP1 expression, and mediate senescence-dependent tumor regression. Furthermore, hypoxia inhibits eIF4E2-GSK3{beta}. Inspiringly, eIF4E2-GSK3{beta} is unique to mammals, which maintains mice viability and prevents liver senescence against physiological hypoxia. Interestingly, this mammalian eIF4E2 protects heart of zebrafish against hypoxia. Together, we identified a mammalian -unique eIF4E2-GSK3{beta} pathway preventing senescence and guarding against hypoxia in vivo.

cell biology↗

Cooperation-based sperm clusters mediate sperm oviduct entry and fertilization

Sperm cooperation has been observed in multiple species, yet its existence and benefit for reproductive success in mammals remains underexplored. Here, combining tissue-clearing with deep three-dimensional imaging, we demonstrate that postcopulatory mouse sperm congregate into unidirectional sperm cooperative clusters at the utero-tubal junction (UTJ), a key physical barrier for passage into the oviduct. Reducing sperm number in male mice by unilateral vasoligation or busulfan-treatment impairs sperm cluster formation and oviduct entry. Interestingly, sperm derived from Tex101-/- mouse has normal number, motility and morphology, yet they cannot form sperm cluster and fail to pass through the UTJ, which is at least in part due to the altered tail beating pattern of the Tex101-/- sperm. Moreover, Tex101-/- sperms defect in oviduct entry cannot be rescued by the presence of wild-type (WT) sperm in the same uteri by sequential mating, suggesting sperm cooperative cluster as an essential behavior contributing to male fertility, which could be related to human infertility or subfertility.

developmental biology↗

Structure, Dynamics, Receptor Binding, and Antibody Binding of Fully-glycosylated Full-length SARS-CoV-2 Spike Protein in a Viral Membrane

The spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mediates host cell entry by binding to angiotensin-converting enzyme 2 (ACE2), and is considered the major target for drug and vaccine development. We previously built fully-glycosylated full-length SARS-CoV-2 S protein models in a viral membrane including both open and closed conformations of receptor binding domain (RBD) and different templates for the stalk region. In this work, multiple s-long all-atom molecular dynamics simulations were performed to provide deeper insight into the structure and dynamics of S protein, and glycan functions. Our simulations reveal that the highly flexible stalk is composed of two independent joints and most probable S protein orientations are competent for ACE2 binding. We identify multiple glycans stabilizing the open and/or closed states of RBD, and demonstrate that the exposure of antibody epitopes can be captured by detailed antibody-glycan clash analysis instead of a commonly-used accessible surface area analysis that tends to overestimate the impact of glycan shielding and neglect possible detailed interactions between glycan and antibody. Overall, our observations offer structural and dynamic insight into SARS-CoV-2 S protein and potentialize for guiding the design of effective antiviral therapeutics.

biophysics↗

Pseudomonas aeruginosa secreted protein PA3611 promotes bronchial epithelial cells epithelial-mesenchymal transition through TGF-β1 inducing p38/miRNA/NF-κB pathway

Pseudomonas aeruginosa (PA) is one of the important pathogens, which has been proven to colonize and cause infection in the respiratory tract of patients with structural lung diseases, and further lead to bronchial fibrosis. Epithelial-Mesenchymal Transition (EMT) of bronchial epithelial cells plays a vital role in the process of bronchial fibrosis. Up to the present, the research on bronchial epithelial cells EMT caused by secreted virulence factors of PA has not been reported. In our present study, we found that PA3611 protein stimulation induced the bronchial epithelial cells EMT with up-regulation of mesenchymal cell markers and down-regulation of epithelial cell markers. Meantime, TGF-{beta}1 secretion was markedly increased, I{kappa}B expression was significantly decreased, and NF-{kappa}B p65 subunit phosphorylation was markedly enhanced, in addition, the levels of miR-3065-3p and miR-6802-3p expression and p38 MAPK phosphorylation were obviously increased in bronchial epithelial cells after PA3611 stimulation, further research revealed that PA3611 promoted EMT occur through TGF-{beta}1 induced p38/miRNA/NF-{kappa}b pathway. The function of PA3611 was also verified in PA-infected rats and results showed that {Delta}PA3611 could reduce lung inflammation and EMT. Overall, our results revealed that PA3611 promotes EMT via simulating the production of TGF-{beta}1 induced p38/miRNA/NF-{kappa}B pathway-dependent manner, suggesting that PA3611 acts as a crucial virulence factor in bronchial epithelial cells EMT process and has potential use as a target for clinical treatment of bronchial EMT and fibrosis caused by chronic PA infection. Author summaryStructural lung disease can increase the chance of chronic infection, including infected by Pseudomonas aeruginosa, which can cause lung structure damages and affect lung functions in further, and forming a vicious circle of intertwining, ultimately, it leads to pulmonary fibrosis. EMT of bronchial epithelial cells plays a vital role in the process of bronchial fibrosis. However, the relationship and mechanism of PA infection leads to the destruction of lung structure and bronchial epithelial cells EMT are still not very clear. We found pseudomonas aeruginosa secreted protein PA3611 can stimulate bronchial epithelial cells EMT through up-regulation of mesenchymal cell markers -SMA and Vimentin expression and down-regulation of epithelial cell markers E-cadherin and Zonula Occludens-1. Meantime, TGF-{beta}1 secretion was markedly increased, I{kappa}B expression was significantly decreased, and NF-{kappa}B p65 subunit phosphorylation was markedly enhanced, in addition, the levels of miR-3065-3p and miR-6802-3p expression and p38 MAPK phosphorylation were obviously increased in bronchial epithelial cells after PA3611 stimulation, further studies suggested that PA3611 was shown to promote EMT occur through TGF-{beta}1 induced p38/miRNA/NF-Kb pathway. Our results revealed that PA3611 promotes EMT via simulating the production of TGF-{beta}1 induced p38/miRNA/NF-{kappa}B pathway-dependent manner, suggesting that PA3611 acts as a crucial virulence factor in bronchial epithelial cells EMT process and as a potential target for the treatment of chronic structural lung diseases.

microbiology↗

Precision Cas9 Genome Editing in vivo with All-in-one, Self-targeting AAV Vectors

Adeno-associated virus (AAV) vectors are important delivery platforms for therapeutic genome editing but are severely constrained by cargo limits, especially for large effectors like Cas9s. Simultaneous delivery of multiple vectors can limit dose and efficacy and increase safety risks. The use of compact effectors has enabled single-AAV delivery of Cas9s with 1-3 guides for edits that use end-joining repair pathways, but many precise edits that correct disease-causing mutations in vivo require homology-directed repair (HDR) templates. Here, we describe single-vector, [~]4.8-kb AAV platforms that express Nme2Cas9 and either two sgRNAs to produce segmental deletions, or a single sgRNA with an HDR template. We also examine the utility of Nme2Cas9 target sites in the vector for self-inactivation. We demonstrate that these platforms can effectively treat two disease models [type I hereditary tyrosinemia (HT-I) and mucopolysaccharidosis type I (MPS-I)] in mice. These results will enable single-vector AAVs to achieve diverse therapeutic genome editing outcomes.

molecular biology↗

Comparative analysis of temporal transcriptome reveals the relationship between pectin degradation and pathogenicity of defoliating Verticillium dahliae to Upland cotton (Gossypium hirsutum)

Verticillium wilt (VW), caused by Verticillium dahliae Kleb., is a major plant disease that causes heavy annual losses around the world, especially in Upland cotton (Gossypium hirsutum). The disease-causing pathogen can be classified into defoliating (D) and non-defoliating (ND) pathotypes based on the induced symptoms. At present, little is known about the complex mechanisms of fungal pathogenicity and cotton resistance to it. Comparative analysis of temporal transcriptome was performed on two V. dahliae strains, Vd_086 (D) and Vd_BP2 (ND), at key development stages (hyphal growth, microsclerotia production, and spore germination) to reveal the functional process on plant defoliation and death. Differentially expressed gene (DEG) analysis revealed a strong correlation between cell wall protein kinase activities and the early pathogenicity of defoliating Vd_086. With weighted gene co-expression network analysis (WGCNA), six specific gene modules were correlated with the biological traits of the fungal samples. Functional enrichment with Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways together with DEG analysis revealed six pectin degrading enzymes including Polygalacturonase gene 1 (PG1), Pectate lyase gene (PEL) and Pectinesterase gene 1 (PME1) expressed in the early development of Vd_086 that may be related to the robust pathogenicity of this strain during the early invasion. The expression of four of these genes was verified by real-time quantitative reverse transcription PCR (qRT-PCR). In addition, we identified Mitogen-Activated Protein Kinase (MAPK) signaling "hub" genes that may regulate these pectinases. In a word, enhanced expression of pectin degradation enzymes is associated with the stronger pathogenicity of Vd_086 than Vd_BP2, especially at early infection stages. The disease-causing capability is likely regulated by MAPK signaling genes. This study provides new insight into molecular mechanisms of the plant-pathogen interaction on the VW disease, facilitating more effective control measures against this pathogen, including molecular breeding for the VW-resistant cotton cultivars. Author summaryVerticillium wilt (VW), caused by fungal pathogen Verticillium dahliae (Vd), is arguably the most devastating disease in cotton production for decades. Molecular biologists and plant breeders have been working hard to identify host plant resistant genes for many years but have met with little success due to the large complex genome of cotton. The V. dahliae strains are grouped in two pathotypes, of which defoliating (D) strains cause total leaf loss of infected cotton plants and non-defoliating (ND) strains do not. Comparative transcriptome analysis of D strain Vd_086 and ND strain Vd_BP2 identified the candidate genes and molecular mechanisms related to the Vd pathogenicity. Besides the difference in pathogenicity, these strains are distinguishable by the rate of hyphal elongation, microsclerotia production, and spore germination. With these phenotypes, transcriptome sequencing of both strains was performed at the three growth phases. By the combination of comparative transcriptomic differentially expressed gene (DEG) analysis and weighted gene correlation network analysis (WGCNA), cell wall-associated pectinase genes were found to be active at hyphal elongation stage of the V. dahliae pathogen and ribosome-related processes were activated for microsclerotia production. Gene modification processes were activated with many protein kinases at spore germination stage that for the next infection cycle. Furthermore, four pectinases in the pentose and glucuronate interconversion (PGI) pathway were identified and verified as highly expressed in the D strain with strong pathogenicity to Upland cotton (Gossypium hirsutum). Our results provided evidence in support of the hypothesis that stronger early pathogenicity of the D strain is resulted from greater plant cell wall pectin degradability. Transcription factors (TFs) and "hub" module genes were identified in searching of protein interaction for possible regulators of the recognized pectinases. TFs involved in mitogen-activated protein kinase (MAPK) signaling pathway were shown to regulate not only hyphal processes but also the entire growth period of V. dahliae. This is the first study known to use module extraction techniques of WGCNA to identify differentially co-expressed genes between two fungal pathotypes of V. dahliae strains. The study provides new insights into molecular mechanisms of the plant-pathogen interaction and may lead to molecular breeding for resistant cotton cultivars to effectively control this devastating disease.

microbiology↗

TALE: Transformer-based protein function Annotation with joint sequence-Label Embedding

MotivationFacing the increasing gap between high-throughput sequence data and limited functional insights, computational protein function annotation provides a high-throughput alternative to experimental approaches. However, current methods can have limited applicability while relying on data besides sequences, or lack generalizability to novel sequences, species and functions. ResultsTo overcome aforementioned barriers in applicability and generalizability, we propose a novel deep learning model, named Transformer-based protein function Annotation through joint sequence-Label Embedding (TALE). For generalizbility to novel sequences we use self attention-based transformers to capture global patterns in sequences. For generalizability to unseen or rarely seen functions, we also embed protein function labels (hierarchical GO terms on directed graphs) together with inputs/features (sequences) in a joint latent space. Combining TALE and a sequence similarity-based method, TALE+ outperformed competing methods when only sequence input is available. It even outperformed a state-of-the-art method using network information besides sequence, in two of the three gene ontologies. Furthermore, TALE and TALE+ showed superior generalizability to proteins of low homology and never/rarely annotated novel species or functions compared to training data, revealing deep insights into the protein sequence-function relationship. Ablation studies elucidated contributions of algorithmic components toward the accuracy and the generalizability. AvailabilityThe data, source codes and models are available at https://github.com/Shen-Lab/TALE Contactyshen@tamu.edu Supplementary informationSupplementary data are available at Bioinformatics online.

bioinformatics↗