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Zhao, H.

Publications and source records attributed to Zhao, H..

At least 343 records · Page 19Linked to original sources

An automated interface for sedimentation velocity analysis in SEDFIT

Sedimentation velocity analytical ultracentrifugation (SV-AUC) is an indispensable tool for the study of particle size distributions in biopharmaceutical industry, for example, to characterize protein therapeutics and vaccine products. In particular, the diffusion-deconvoluted sedimentation coefficient distribution analysis, in the software SEDFIT, has found widespread applications due to its relatively high resolution and sensitivity. However, a lack of available software compatible with Good Manufacturing Practices (GMP) has hampered the use of SV-AUC in this regulatory environment. To address this, we have created an interface for SEDFIT so that it can serve as an automatically spawned module with controlled data input through command line parameters and output of key results in files. The interface can be integrated in custom GMP compatible software, and in scripts that provide documentation and meta-analyses for replicate or related samples, for example, to streamline analysis of large families of experimental data, such as binding isotherm analyses in the study of protein interactions. To test and demonstrate this approach we provide a MATLAB script mlSEDFIT.

biophysics↗

SKP2 knockout in Rb1/p53 deficient mouse models of osteosarcoma induces immune infiltration and drives a transcriptional program with a favorable prognosis

PurposeOsteosarcoma (OS) is an aggressive bone malignancy with a poor prognosis. One putative proto-oncogene in OS is SKP2, encoding a substrate recognition factor of the SCF E3 ubiquitin ligase. We previously demonstrated that SKP2 knockout in murine OS improved survival and delayed tumorigenesis. Here we aim to define the SKP2 drives transcriptional program and its clinical implication in OS. Experimental DesignWe performed RNA-sequencing (RNA-seq) on tumors from a transgenic OS mouse model with conditional Trp53 and Rb1 knockouts in the osteoblast lineage ("DKO": Osx1-Cre;Rb1lox/lox;p53lox/lox) and a triple-knockout model with additional Skp2 germline knockout ("TKO": Osx1-Cre;Rb1lox/lox;p53lox/lox;SKP2-/-). We validated our RNA-seq findings using qPCR and immunohistochemistry. To investigate the clinical implications of our results, we analyzed a human OS patient cohort ("NCI-TARGET OS") with RNA-seq and clinical data. ResultsWe found large differences in gene expression after SKP2 knockout. Strikingly, we observed increased expression of genes related to immune microenvironment infiltration in TKO tumors. We observed significant increases in signature genes for macrophages and to a lesser extent, T cells, B cells and vascular cells. We also uncovered a set of relevant transcription factors that may mediate the changes. In OS patient cohorts, high expression of genes upregulated in TKO was correlated with favorable overall survival, which was largely explained by the macrophage gene signatures. This relationship was further supported by our finding that SKP2 expression was negatively correlated with macrophage infiltration in the NCI-TARGET OS and the TCGA Sarcoma cohort. ConclusionOur findings indicate that SKP2 may mediate immune exclusion from the OS tumor microenvironment, suggesting that SKP2 modulation in OS may induce anti-tumor immune activation. Translational RelevanceOsteosarcoma (OS) is an aggressive bone malignancy. Standard care treatment involving chemotherapy and surgery remains unchanged for decades. OS prognosis remains poor and targeted therapies are critically needed. Immunotherapy failed in clinical trials despite extensive genomic instability, suggesting OS tumors employ active immune exclusion. One putative oncogene in OS is SKP2, which activates cell proliferation. SKP2 is correlated with worse prognosis in patients and knockout of SKP2 improved survival in murine OS. Here, we performed comparative transcriptomic analysis between transgenic OS murine models with SKP2 knockout and controls. We showed that SKP2 knockout dramatic increased immune gene expression largely due to macrophage, and to a lesser extent lymphocytes, infiltration. Interestingly, we found that the increased gene program uncovered from our SKP2 knockout model was correlated with improved survival in OS patients. Our findings indicate a completely new function for SKP2 in mediating immune exclusion in sarcoma and suggest that SKP2 inhibition may lead to improved immune activation and potential treatment.

cancer biology↗

Nitrogen starvation causes lipid remodeling in Rhodotorula toruloides

The oleaginous yeast Rhodotorula toruloides is a promising chassis organism for the biomanufacturing of value-added bioproducts. It can accumulate lipids at a high fraction of biomass. However, metabolic engineering efforts in this organism have progressed at a slower pace than those in more extensively studied yeasts. Few studies have investigated the lipid accumulation phenotype exhibited by R. toruloides under nitrogen limitation conditions. Consequently, there have been only a few studies exploiting the lipid metabolism for higher product titers. Here, we present a multi-omic investigation of the lipid accumulation phenotype under nitrogen limitation. Through an integrative lens of transcriptomic and lipidomic analysis, we identify that R. toruloides undergoes lipid remodeling during nitrogen limitation, wherein the pool of phospholipids gets remodeled to mostly storage lipids. This insight into the mechanisms of lipid accumulation can lead to the success of future metabolic engineering strategies for overproduction of oleochemicals. HighlightsO_LIThe oleaginous yeast R. toruloides displays enhanced lipid accumulation during nitrogen starvation. C_LIO_LIA multi-omic investigation of the lipid accumulation phenotype was carried out. C_LIO_LILipid remodeling was observed during the accumulation phase, wherein carbon was transferred from phospholipids to storage lipids. C_LIO_LIMulti-omic analysis suggested that selective regulation within lipid biosynthesis controls for the specific increase of storage lipids. C_LI

systems biology↗

Integrating gene mutation spectra from tumors and the general population with gene expression topological networks to identify novel cancer driver genes

BackgroundUnderstanding the genetics underlying cancer development and progression is the most important goal of biomedical research to improve patient survival rates. Recently, researchers have proposed computationally combining the mutational burden with biological networks as a novel means to identify cancer driver genes. However, these approaches treated all mutations as having the same functional impact on genes and incorporated gene-gene interaction networks without considering tissue specificity, which may have hampered our ability to identify novel cancer drivers. MethodsWe have developed a framework, DGAT-cancer that integrates the predicted pathogenicity of somatic mutation in cancers and germline variants in the healthy population, with topological networks of gene expression in tumor tissues, and the gene expression levels in tumor and paracancerous tissues in predicting cancer drivers. These features were filtered by an unsupervised approach, Laplacian selection, and those selected were combined by Hotelling and Box-Cox transformations to score genes. Finally, the scored genes were subjected to Gibbs sampling to determine the probability that a given gene is a cancer driver. ResultsThis method was applied to nine types of cancer, and achieved the best area under the precision-recall curve compared to three commonly used methods, leading to the identification of 571 novel cancer drivers. One of the top genes, EEF1A1 was experimentally confirmed as a cancer driver of glioma. Knockdown of EEF1A1 led to a ~ 41-50% decrease in glioma size and improved the temozolomide sensitivity of glioma cells. ConclusionBy combining the pathogenic status of mutational spectra in tumors alongside the spectrum of variation in the healthy population, with gene expression in both tumors and paracancerous tissues, DGAT-cancer has significantly improved our ability to detect novel cancer driver genes.

bioinformatics↗

An end-to-end pipeline for succinic acid production at an industrially relevant scale using Issatchenkia orientalis

As one of the top value-added chemicals, succinic acid has been the focus of numerous metabolic engineering campaigns since the 1990s. However, microbial production of succinic acid at an industrially relevant scale has been hindered by high downstream processing costs arising from neutral pH fermentation. Here we describe the metabolic engineering of Issatchenkia orientalis, a non-conventional yeast with superior tolerance to highly acidic conditions, for cost-effective succinic acid production. Through deletion of byproduct pathways, transport engineering, and expanding the substrate scope, the resulting strains could produce succinic acid at the highest titers in sugar-based media at low pH (pH 3) in fed-batch fermentations using bench-top reactors, i.e. 109.5 g/L in minimal medium and 104.6 g/L in sugarcane juice medium. We further performed batch fermentation in a pilot-scale fermenter with a scaling factor of 300x, achieving 63.1 g/L of succinic acid using sugarcane juice medium. A downstream processing comprising of two-stage vacuum distillation and crystallization enabled direct recovery of succinic acid, without further acidification of fermentation broth, with an overall yield of 64.0%. Finally, we simulated an end-to-end low-pH succinic acid production pipeline, and techno-economic analysis and life cycle assessment indicate our process is financially viable and can reduce life cycle greenhouse gas emissions by 34-90% relative to fossil-based production processes. We expect I. orientalis can serve as a general industrial platform for the production of a wide variety of organic acids.

synthetic biology↗

Discovery of microRNA-derived RNAs and proteins in human cells

MicroRNAs (miRNAs) are short noncoding RNAs that can regulate gene expression through the binding of their 5-ends to mRNAs. However, the biological effects of miRNA binding via their 3-ends remain unclear. Here, we discover that the exact reverse pairing of the 3-ends of miRNAs or miRNA-like RNAs, collectively termed microsized RNAs (msRNAs), with template RNAs can initiate the production of msRNA-derived RNAs (msdRs), which can subsequently be translated into polypeptides (msdPs). Using 2,632 human msRNAs from miRBase, 11,121 msdRs and 1,239 msdPs were predicted based on a 15-nucleotide pairing threshold, and the presence of representative msdRs and msdPs was confirmed in human cells. Of clinical relevance, msdP0188 is highly expressed in human lung and breast cancers, and its corresponding msRNAs and msdRs represent novel anti-cancer targets. Notably, inhibiting telomerase reverse transcriptase, a putative RNA-dependent RNA polymerase identified by bioinformatic screening, led to reduced levels of msdP0188 in human cancer cells. Our findings reveal a novel "msRNA [->] msdR [->] msdP" axis, expanding the classical central dogma and predicting many previously unrecognized RNAs and polypeptides with potential biological functions in human cells and other systems.

cell biology↗

A 1.5 Mb continuous endogenous viral element region in the arbuscular mycorrhizal fungus Rhizophagus irregularis

Most fungal viruses are RNA viruses and no double-stranded DNA virus that infects fungi is known to date. A recent study detected DNA polymerase genes that originated from large dsDNA viruses in the genomes of basal fungi, suggestive of the existence of dsDNA viruses capable of infecting fungi. In this study, we searched for viral infection signatures in chromosome-level genome assemblies of the arbuscular mycorrhizal fungus Rhizophagus irregularis. We identified a continuous 1.5 Mb putative viral region on a chromosome in R. irregularis strain 4401. Phylogenetic analyses revealed that the viral region is related to viruses in the family Asfarviridae of the phylum Nucleocytoviricota. Single-copy marker genes from Nucleocytoviricota were detected as single-copy genes in the viral region. Furthermore, this viral region was absent in the genomes of four other R. irregularis strains and had fewer signals of fungal transposable elements than the other genomic regions. These results suggest a recent and single insertion of a large dsDNA viral genome in the genome of this fungal strain, providing strong evidence of the recent infection of the fungus by a dsDNA virus.

microbiology↗

Pan-cancer analysis of the ion permeome reveals functional regulators of glioblastoma aggression

Ion channels, transporters, and other ion-permeating proteins, collectively comprising the ion permeome (IP), are common drug targets. However, their roles in cancer are understudied. Our integrative pan-cancer analysis shows that IP genes display highly-elevated expression patterns in subsets of cancer samples significantly more often than expected transcriptome-wide. To enable target identification, we identified 410 survival-associated IP genes in 29 cancer types using a machine learning approach. Notably, GJB2 and SCN9A show prominent expression in neoplastic cells and associate with poor prognosis in glioblastoma (GBM), the most common and aggressive brain cancer. GJB2 or SCN9A knockdown in patient-derived GBM cells induces transcriptome-wide changes involving neural projection and proliferation pathways, impairs cell viability and tumor sphere formation, mitigates tunneling nanotube formation, and extends the survival of GBM-bearing mice. Thus, aberrant activation of IP genes appears as a pan-cancer feature of tumor heterogeneity that can be exploited for mechanistic insights and therapy development.

cancer biology↗

Repurposing the Memory-promoting Meclofenoxate Hydrochloride as a Treatment for Parkinson's Disease through Integrative Multi-omics analysis

Parkinson s disease (PD) is a devastating neurodegenerative disorder with growing prevalence worldwide and, as yet, no effective treatment. Drug repurposing promises to be invaluable for the identification of novel therapeutics for the treatment of PD due to the associated shortened drug development time, fewer safety concerns, and reduced costs. Here, we compiled gene expression data from 1,231 healthy human brains and 357 PD patients across ethnicities, brain regions, Braak stages, and disease status. By integrating them with multiple-source PD-associated genomic data, we found a conserved PD-associated gene co-expression module, and its alignment with the CMAP database successfully identified 15 drug candidates. Among these, we selected meclofenoxate hydrochloride (MH) and sodium phenylbutyrate (SP) for experimental validation because they are capable of passing through the blood brain barrier. In primary neurons, MH was found to prevent the neuronal death and synaptic damage associated with PD and to reverse the abnormal mitochondrial metabolism caused by PD. In hippocampal tissues, MH and SP were found to prevent the destruction of mitochondria, to reduce lipid peroxidation and to protect dopamine synthesis by PET-CT examination, malondialdehyde (MAD) testing and glutathione (GSH) testing, and immunohistochemical tests. Finally, MH was found to have the ability to improve gait behavior, and reduce anhedonic and depressive-like behaviors that are characteristics of PD mice. Taken together, our findings support the contention that MH may have the potential to ameliorate PD by improving mitochondrial metabolism and brain function.

biochemistry↗

Identification of a novel MCR-1 variant displaying low level of co-resistance to β-lactam antibiotics that uncovers a potential novel antimicrobial peptide

The emerging and global spread of a novel plasmid-mediated colistin resistance gene, mcr-1, threatens human health. It is accepted that MCR-1 affects bacterial fitness, and this fitness cost correlates with bacterial membrane lipid A perturbation. However, the detailed molecular mechanism remains unclear. Here, we screened out a novel MCR-1 variant, named M6, with a two-point mutation that rendered a low level of co-resistance to {beta}-lactam antibiotics. Compared to wild-type (WT) MCR-1, this variant caused severe lipid A perturbation resulting in peptidoglycan layer remodelling and thus resulted in phenotypic co-resistance to {beta}-lactams. Moreover, we found that a lipid A loading cavity is localized at the linker domain of MCR-1 and governs colistin resistance and bacterial membrane permeability, and the mutated pocket of M6 facilitates the binding affinity of lipid A. More importantly, synthetic peptides derived from M6 achieved broad-spectrum antimicrobial activity. These findings provide insights into a potential vulnerability that could be exploited in future antimicrobial drug design.

microbiology↗

Duckweed evolution: from land back to water

Terrestialization is supposedly an important evolutionary process plant experience. However, directions of land back to water acquired little attention. Here we integrate multiproxy evidence to elucidate the evolution of duckweed. Three genera of duckweed show chronologically gradient degeneration in roots structure and stomatal function and decrease in lignocellulose content, accompanied by gradual contraction in relevant gene numbers and/or decline in transcription. The gene numbers in the main phytohormonal pathway are also gradually decreased. The co-action of auxin and rhizoid development gene causes a gradual decrease in adventitious roots. The significant expansion of the flavonoid pathway is also related to the adaptation of duckweed to floating growth. This study reconstructs the evolution history of duckweeds from land back to water, reverse to that of early land plants. SummaryWith terrestrialization being the popularly acknowledged plant evolutionary process, little is known about the evolution of higher plant from land back to water. Here we integrate multiproxy evidence to elucidate the gradual reverse evolution of duckweed. Three genera of duckweed show chronologically gradient degeneration in the structure of roots, the function of stomata, and decrease in lignocellulose content, accompanied by gradient contraction in relevant gene numbers and/or decline in transcript expression. The gene numbers in the main phytohormonal pathway are also gradually decreased. The co-action of auxin and rhizoid development gene causes a gradual decrease in adventitious roots. The significant expansion of the flavonoid pathway is also highly related to the adaptation of duckweed to floating growth. Our study combined with the fossil evidence reconstruct the evolution history of duckweeds from land back to water, reverse to that of early land plants. This study reconstructed the process of how a land plant returns to water, a reverse evolutionary approach which is different from what we studied in textbook about plant terrestrialization. This finding could be helpful for us to deeply and widely understand the adaptation of plant to the environment, and to expand and deepen the knowledge of evolution theory.

evolutionary biology↗

Artificially cultivated duckweed: a high-efficiency starch producer

The increasing demand for starch has been a social struggle. We report a new technology that efficiently produces starch from duckweed. Although Landoltia punctata has a dramatic contraction of gene families, its starch content and productivity reached 72.2% (dry basis) and 10.4 g m-2 d-1 in 10 days, equivalent to a yield of 38.0 t ha-1 y-1 under nutrient limitation and CO2 elevation treatment. Meanwhile, we also examined the mechanism of duckweeds high starch accumulation. This is exhibited in the regulation of DNA methylation and transcription factors as well as the significantly up-regulated transcription levels and the increased enzyme activities of key genes in starch biosynthesis. Meantime, while nitrogen redistribution was enhanced, sucrose biosynthesis and transportation, and lignocellulose biosynthesis were all reduced. These alterations led to a reduction in lignocellulose and protein content and ultimately an increase in an accumulation of starch in the chloroplast. This work demonstrates duckweeds potential of being a highly efficient starch producer.

plant biology↗

SMAD4: A Critical Regulator of Cardiac Neural Crest Cell Fate and Vascular Smooth Muscle Differentiation

BackgroundThe pharyngeal arch arteries (PAAs) are precursor vessels which remodel into the aortic arch arteries (AAAs) during embryonic cardiovascular development. Cardiac neural crest cells (NCs) populate the PAAs and differentiate into vascular smooth muscle cells (vSMCs), which is critical for successful PAA-to-AAA remodeling. SMAD4, the central mediator of canonical TGF{beta} signaling, has been implicated in NC-to-vSMC differentiation; however, its distinct roles in vSMC differentiation and NC survival are unclear. ResultsHere, we investigated the role of SMAD4 in cardiac NC differentiation to vSMCs using lineage-specific inducible mouse strains in an attempt to avoid early embryonic lethality and NC cell death. We found that with global SMAD4 loss, its role in smooth muscle differentiation could be uncoupled from its role in the survival of the cardiac NC in vivo. Moreover, we found that SMAD4 may regulate the induction of fibronectin, a known mediator of NC-to-vSMC differentiation. Finally, we found that SMAD4 is required in NCs cell-autonomously for NC-to-vSMC differentiation and for NC contribution to and persistence in the pharyngeal arch mesenchyme. ConclusionsOverall, this study demonstrates the critical role of SMAD4 in the survival of cardiac NCs, their differentiation to vSMCs, and their contribution to the developing pharyngeal arches.

developmental biology↗

Degenerated CRISPRs widely regulate Cas expression to balance immunity and cost

CRISPR RNAs (crRNAs) and Cas proteins together provide prokaryotes with adaptive immunity against genetic invaders. How Cas expression is fine-tuned to avoid energy burden while satisfying the dynamic need of crRNAs remains poorly understood. Here we experimentally demonstrated widespread degenerated mini-CRISPRs encode CreR (Cas-regulating) RNAs to mediate autorepression of type I-B, I-E and V-A Cas proteins, based on their partial complementarity to cas promoters. This autorepression decreases energy burden and autoimmune risks, thus mitigating the fitness cost on host cell, and remarkably, senses and responds to alterations in the volume of canonical crRNAs, which compete with CreR for Cas proteins. Moreover, CreR-guided Cas autorepression can be subverted by diverse anti-CRISPR (Acr) proteins that destruct Cas proteins, which in turn replenishes the weapon depot. Our data unveil a general degenerated crRNA-guided autorepression paradigm for diverse Cas effectors, which highlights the intricate (self-)regulation of CRISPR-Cas and its transcriptional counterstrategy against Acr attack.

microbiology↗

Infinite Physical Monkey: Do Deep Learning Methods Really Perform Better in Conformation Generation?

Conformation Generation is a fundamental problem in drug discovery and cheminformatics. Generally, it can be categorized into three different classes according to physical scales, i.e., micro molecule (organic), meso molecule (nano particle-like), and macro molecule (protein and nucleic acid). Organic molecule conformation generation, particularly in vacuum and protein pocket environments, is most relevant to drug design. Recently, with the development of geometric neural networks, the data-driven schemes have been successfully applied in this field, both for molecular conformation generation (in vacuum) and binding pose generation (in protein pocket). The former beats the traditional ETKDG method, while the latter achieves similar accuracy compared with the widely used molecular docking software. Although these methods have shown promising results for real-world drug design campaigns, some researchers have recently questioned whether deep learning (DL) methods perform better in molecular conformation generation via a "parameter-free" method. To our surprise, what they have designed is some kind analogous to the famous infinite monkey theorem, the monkeys that are even equipped with physics education. To discuss the feasibility of their proving, we constructed a real infinite stochastic monkey for molecular conformation generation, showing that even with a more stochastic sampler for geometry generation, the coverage of the benchmark QM-computed conformations are higher than those of most DL-based methods. By extending their physical monkey algorithm for binding pose prediction (with 2000 random samples), we also discover that the successful docking rate also achieves near-best performance among existing DL-based docking models. Thus, though their conclusions are right, their proof process needs more concern. In addition to evaluating the rationality of their algorithms and conclusions, we dig into the inspirations of infinite physical monkeys. We find that, for docking pose generation, DL-based models truly learn the interaction rules between residues and ligands, and discover an inductive bias hidden in the training of the pocket-given docking problem. The code of the proposed algorithm could be found at: https://github.com/HaotianZhangAI4Science/infinite-physical-monkey. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/531607v2_ufig1.gif" ALT="Figure 1"> View larger version (126K): org.highwire.dtl.DTLVardef@188ac2eorg.highwire.dtl.DTLVardef@1e006f3org.highwire.dtl.DTLVardef@e83f8forg.highwire.dtl.DTLVardef@1a4c7cd_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOTOC:C_FLOATNO Infinite Physical Monkey. This image was created with the assistance of DALL{middle dot}E 2 C_FIG

biophysics↗

Genome mining unveils a class of ribosomal peptides with two amino termini

The era of inexpensive genome sequencing and improved bioinformatics tools has reenergized the study of natural products, including the ribosomally synthesized and post-translationally modified peptides (RiPPs). In recent years, RiPP discovery has challenged preconceptions about the scope of post-translational modification chemistry, but genome mining of new RiPP classes remains an unsolved challenge. Here, we report a RiPP class defined by an unusual (S)-N2,N2-dimethyl-1,2-propanediamine (Dmp)-modified C-terminus, which we term the daptides. Nearly 500 daptide biosynthetic gene clusters (BGCs) were identified by analyzing the RiPP Recognition Element (RRE), a common substrate-binding domain found in half of prokaryotic RiPP classes. A representative daptide BGC from Microbacterium paraoxydans DSM 15019 was selected for experimental characterization. Derived from a C-terminal threonine residue, the class-defining Dmp is installed over three steps by an oxidative decarboxylase, aminotransferase, and methyltransferase. Daptides uniquely harbor two positively charged termini, and thus we suspect this modification could aid in membrane targeting, as corroborated by hemolysis assays. Our studies further show that the oxidative decarboxylation step requires a functionally unannotated accessory protein. Fused to the C-terminus of the accessory protein is an RRE domain, which delivers the unmodified substrate peptide to the oxidative decarboxylase. This discovery of a class-defining post-translational modification in RiPPs may serve as a prototype for unveiling additional RiPP classes through genome mining.

biochemistry↗

Condensate-driven interfacial forces reposition DNA loci and measure chromatin viscoelasticity

Biomolecular condensates assemble in living cells through phase separation and related phase transitions. An underappreciated feature of these dynamic molecular assemblies is that they form interfaces with cellular structures, including membranes, cytoskeleton, DNA and RNA, and other membraneless compartments. These interfaces are expected to give rise to capillary forces, but there are few ways of quantifying and harnessing these forces in living cells. Here, we introduce VECTOR (ViscoElastic Chromatin Tethering and ORganization), which uses light-inducible biomolecular condensates to generate capillary forces at targeted DNA loci. VECTOR can be utilized to programmably reposition genomic loci on a timescale of seconds to minutes, quantitatively revealing local heterogeneity in the viscoelastic material properties of chromatin. These synthetic condensates are built from components that naturally form liquid-like structures in living cells, highlighting the potential role for native condensates to generate forces and do work to reorganize the genome and impact chromatin architecture.

biophysics↗

PrePPI: A structure informed proteome-wide database of protein-protein interactions

We present an updated version of the Predicting Protein-Protein Interactions (PrePPI) webserver which predicts PPIs on a proteome-wide scale. PrePPI combines structural and non-structural clues within a Bayesian framework to compute a likelihood ratio (LR) for essentially every possible pair of proteins in a proteome; the current database is for the human interactome. The structural modeling (SM) clue is derived from templatebased modeling and its application on a proteome-wide scale is enabled by a unique scoring function used to evaluate a putative complex. The updated version of PrePPI leverages AlphaFold structures that are parsed into individual domains. As has been demonstrated in earlier applications, PrePPI performs extremely well as measured by receiver operating characteristic curves derived from testing on E. coli and human protein-protein interaction (PPI) databases. A PrePPI database of ~1.3 million human PPIs can be queried with a webserver application that comprises multiple functionalities for examining query proteins, template complexes, 3D models for predicted complexes, and related features (https://honiglab.c2b2.columbia.edu/PrePPI). PrePPI is a state-of- the-art resource that offers an unprecedented structure-informed view of the human interactome. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=68 SRC="FIGDIR/small/530276v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@b66c15org.highwire.dtl.DTLVardef@71d817org.highwire.dtl.DTLVardef@21d984org.highwire.dtl.DTLVardef@4f6f55_HPS_FORMAT_FIGEXP M_FIG C_FIG

systems biology↗