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Biology subjects

Lan, F.

Publications and source records attributed to Lan, F..

At least 19 recordsLinked to original sources

Imageomics defines granular morphological changes of human skin with age and reveals a rejuvenating effect of xenografting

Rejuvenating aging human skin is a major therapeutic goal, but objective, quantitative measures of intrinsic aging are limited. We performed a cross-sectional histological study of UV-protected buttock and abdominal skin in adults spanning multiple decades of life to identify features that reliably track age. Epidermal thickness measured between rete ridges was unchanged, but rete ridge size declined linearly with age: ridges became shorter and thinner in both sites, though rete ridge number decreased only in the abdomen. Consistent with these structural changes, proliferative cells (Ki67+) per ridge and expression of integrin {beta}4 (ITGB4), a putative stem-cell marker, were reduced in aged skin. We combined these biomarkers into a predictive model that estimated skin age more accurately than any single marker. To test whether the model detects longitudinal change, we analyzed aged abdominal skin before and after xenografting onto young or aged mice, a procedure previously reported to rejuvenate human skin in young but not aged recipient mice. Both individual biomarkers and the imaging model indicated rejuvenation regardless of host age; however, notably, engraftment efficiency was lower in aged hosts, with surviving grafts showing younger histological phenotypes. These results provide quantitative criteria for assessing intrinsic skin aging and suggest that the process of engraftment itself is sufficient to induce rejuvenation-like changes.

pathology↗

KDM7B-mediated demethylation of RNF113A regulates small cell lung cancer sensitivity to alkylation damage

Chemoresistance remains a major obstacle to effective cancer treatment, often driven by enhanced DNA repair mechanisms that enable tumor cells to withstand genotoxic therapies. One such pathway involves the atypical DNA damage repair complex ALKBH3-ASCC, activated by the E3 ligase RNF113A in response to alkylation damage. We previously showed that SMYD3-dependent methylation of RNF113A stimulates this pathway, enhancing DNA repair and promoting resistance. Here, we identify KDM7B/PHF8 as the bona fide RNF113A demethylase, establishing one of the first functional examples of a dynamic, reversible non-histone methylation event regulating genome integrity. KDM7B antagonizes SMYD3 activity by maintaining low levels of methylated RNF113A, thereby limiting ASCC activation and sensitizing cancer cells to alkylating agents. To dissect this regulation in depth, we focused on small cell lung cancer (SCLC), a particularly aggressive malignancy characterized by limited therapeutic options and rapid acquisition of resistance. In SCLC, high KDM7B levels correlate with improved patient prognosis, whereas xenografts with reduced expression exhibit diminished responses to alkylating treatment. Moreover, CRISPR-based on/off modulation of KDM7B in genetically engineered SCLC mouse models demonstrates its central role in determining tumor response to chemotherapy. Our findings position the RNF113A-ASCC axis as a central modulator of chemoresistance, regulated through a post-translational methylation switch representing an innovative therapeutic vulnerability that could be exploited to enhance the efficacy of alkylating agents. Targeting this pathway may provide new opportunities to overcome chemoresistance, with KDM7B levels serving as a predictive biomarker to guide treatment in SCLC.

cell biology↗

H3K4me1 directs H3K36me2 and H3K36me3 deposition in land plants

Monomethylation of histone H3 lysine 4 (H3K4me1) marks enhancers in mammals. However, the function of H3K4me1 in plants remains largely unclear. Here, we analyzed the genome-wide distribution of H3K4me1 in diverse species across evolution, revealing a distinctive H3K4me1 distribution pattern in land plants. To explore the function of H3K4me1 in plants, we identified an H3K4me1-specific reader protein, Early heading date 3 (Ehd3), and solved the structure of Ehd3 in complex with the H3K4me1 peptide, revealing a unique binding module differing from the previously reported PHD finger proteins. We further identified an Ehd3-binding protein, SET domain group 724 (SDG724), and the deletion of either Ehd3 or SDG724 caused similar defects in plant phenotype and changes in transcriptome and epigenome profiles. Both Ehd3 and SDG724 are enriched at chromatin regions marked by H3K4me1 but not H3K4me2 or H3K4me3. Ehd3 activates the H3K36 methyltransferase SDG724, and H3K36me2/me3 are colocalized with H3K4me1 in the genomes of land plants. Collectively, our results reveal that H3K4me1 directs the establishment of H3K36me2 and H3K36me3 in land plants.

molecular biology↗

Dual function of DOT1L suppresses tumor intrinsic immunogenicity in hepatocellular carcinoma

Immune checkpoint inhibitor (ICB) therapy for many cancers remains limited in patients overall response rate. Discovery and development of more effective combinatorial approaches is urgent. Here, through CRISPR/Cas9 genetic screens, we identify DOT1L as a versatile epigenetic factor that functions to suppress tumor-intrinsic immunity through a dual mechanism. Depletion of DOT1L induces the expression of transposable elements and subsequent type I interferon (IFN) response, and meanwhile lowers ZEB1 levels to further unleash the expression of immune-related genes. In turn, we demonstrate that DOT1L loss or treatment with the clinical stage inhibitor EPZ-5676 sensitizes tumors to ICB with increased immune infiltration in mice. More importantly, EPZ-5676 treatment alone is sufficient to enhance antitumor immunity in humanized mice. TCGA data analysis reveals an inverse correlation between DOT1L expression and IFN signatures across multiple cancer types. These findings provide a rationale for targeting DOT1L to improve tumor immunogenicity and overcome immunotherapy resistance. One Sentence SummaryCRISPR genetic screens identified DOT1L as a potential suppressor of tumor intrinsic immunogenicity

cell biology↗

IGF2 mediates Hippo signaling to control liver size

The Hippo pathway is a central mechanism in organ size control, but the mediator for its function remains elusive. Here, we show that the expression of insulin-like growth factor II (IGF2) is directly induced by YAP/TAZ transcription cofactors of the Hippo pathway in a developmental stage- and cell type-specific manner. In mouse livers, Igf2 expression is sustained by YAP/TAZ in hepatoblasts and immature hepatocytes at fetal and neonatal stages, coupling with rapid cell proliferation and liver size expansion, whereas turned off in matured hepatocytes following YAP/TAZ inactivation to prevent liver overgrowth. In contrast, YAP/TAZ fails to regulate Igf2 expression in cholangiocytes and diverse liver mesenchymal cells where epigenetic barriers, including DNA and histone methylation, are implanted near Igf2 promoters. Furthermore, IGF2 activates IGF1R signaling and promotes normal and neoplastic liver growth, while the inactivation of IGF2 or IGF1R effectively blocks YAP/TAZ-induced hepatomegaly and hepatoblastoma. In conclusion, our findings reveal that IGF2 is a bona fide mediator of the Hippo pathway, indicating a fundamental role of the Hippo-IGF2-IGF1R signaling axis in organ size regulation and malignancies.

cell biology↗

SMYD5 is a ribosomal methyltransferase that catalyzes RPL40 lysine methylation to enhance translation output and promote hepatocellular carcinoma

While lysine methylation is well-known for regulating gene expression transcriptionally, its implications in translation have been largely uncharted. Trimethylation at lysine 22 (K22me3) on RPL40, a core ribosomal protein located in the GTPase activation center (GAC), was first reported 27 years ago. Yet, its methyltransferase and role in translation remain unexplored. Here, we report that SMYD5 has robust in vitro activity toward RPL40 K22 and primarily catalyzes RPL40 K22me3 in cells. The loss of SMYD5 and RPL40 K22me3 leads to reduced translation output and disturbed elongation as evidenced by increased ribosome collisions. SMYD5 and RPL40 K22me3 are upregulated in hepatocellular carcinoma (HCC) and negatively correlated with patient prognosis. Depleting SMYD5 renders HCC cells hypersensitivity to mTOR inhibition in both 2D and 3D cultures. Additionally, the loss of SMYD5 markedly inhibits HCC development and growth in both genetically engineered mouse (GEM) and patient-derived xenograft (PDX) models, with the inhibitory effect in the PDX model further enhanced by concurrent mTOR suppression. Our findings reveal a novel role of the SMYD5 and RPL40 K22me3 axis in translation elongation and highlight the therapeutic potential of targeting SMYD5 in HCC, particularly with concurrent mTOR inhibition. This work also broadens the understanding of lysine methylation, extending its significance from transcriptional regulation to translational control.

cancer biology↗

Optimization of gene knockout approaches and practical solutions to sgRNA selection challenges in hPSCs with inducible Cas9 system

RationaleCRISPR/Cas9 has been extensively used to knock out genes, allowing the study of genetic loss-of-function in human pluripotent stem cells (hPSCs). However, the current use of the Cas9-sgRNA plasmid or iCas9 system for gene editing in hPSCs has resulted in limited and inconsistent editing efficiency, as well as labor-intensive work. Additionally, identifying single-guide RNAs (sgRNAs) with high cleavage efficiency and distinguishing them from ineffective ones, which efficiently induce frameshift INDELs (Indels and Deletions) but fail to eliminate target proteins expression, are major challenges in gene knockout experiments. MethodsThis study addresses above issues using an optimized doxycycline-induced spCas9-expressing hPSCs (hPSCs-iCas9) system. We initially developed this system by optimizing a number of parameters to maximize INDELs introducing efficiency in hPSCs-iCas9 cells. The INDELs determined by this system were then compared to predicted scores from three cleavage efficiency scoring algorithms to validate the algorithms accuracy and consistency. Furthermore, we conducted gene knockout using a set of sgRNAs targeting different exons of the ACE2 gene to achieve approximately 80% INDELs for each targeting locus. Western blotting was then performed to detect ACE2 protein expression levels, enabling the identification of potentially ineffective sgRNAs. ResultsSeveral critical factors, including cell tolerance to nucleofection stress, sgRNA stability, nucleofection frequency, and the cell-to-sgRNA ratio, were found to have significant impact on editing efficiency in hPSCs-iCas9. Fine-tuning these parameters markedly improved this efficiency, resulting in up to 93% INDELs for single gene knockout. The three scoring algorithms exhibited significant differences or even conflicts in scoring cleavage efficiency. Through comparing experimental observations to predicted scores, we discovered that the Benchling algorithm outperformed the other two in terms of accuracy and consistency. Furthermore, a sgRNA targeting exon 2 of ACE2 gene was quickly identified as ineffective, as evidenced by the edited cells pool containing 80% INDELs while ACE2 protein expression retained unchanged detected by Western blot. ConclusionThe findings of this study offer valuable insights into the optimal design of gene knockout experiments in hPSCs and provide practical solutions to sgRNA selection challenges for gene editing.

cell biology↗

In vivo proximity proteomics uncovers palmdelphin (PALMD) as a Z-line-associated mitigator of isoproterenol-induced cardiac injury

Z-lines are core ultrastructural organizers of cardiomyocytes that modulate many facets of cardiac pathogenesis. Yet a comprehensive proteomic atlas of Z-line-associated components remain incomplete. Here, we established an adeno-associated virus (AAV)-delivered, cardiomyocyte-specific, proximity-labeling approach to characterize the Z-line proteome in vivo. We found palmdelphin (PALMD) as a novel Z-line-associated protein in both adult murine cardiomyocytes and human pluripotent stem cell-derived cardiomyocytes. Germline and cardiomyocyte-specific palmd knockout mice were grossly normal at baseline but exhibited compromised cardiac hypertrophy and aggravated cardiac injury upon long-term isoproterenol treatment. By contrast, cardiomyocyte-specific PALMD overexpression was sufficient to mitigate isoproterenol-induced cardiac injury. PALMD ablation perturbed transverse tubules (T-tubules) and their association with sarcoplasmic reticulum, which formed the Z-line-associated junctional membrane complex (JMC) essential for calcium handling and cardiac function. These phenotypes were associated with disrupted localization of T-tubule markers caveolin-3 (CAV3) and junctophilin-2 (JPH2) and the reduction of nexilin (NEXN) protein, a crucial Z-line-associated protein that is essential for both Z-line and JMC structures and functions. PALMD was found to interact with NEXN and enhance its protein stability while the Nexn mRNA level was not affected. Together, this study discovered PALMD as a potential target for myocardial protection and highlighted in vivo proximity proteomics as a powerful approach to nominate novel players regulating cardiac pathogenesis. HighlightsO_LIIn vivo proximity proteomics uncover novel Z-line components that are undetected in in vitro proximity proteomics in cardiomyocytes. C_LIO_LIPALMD is a novel Z-line-associated protein that is dispensable for baseline cardiomyocyte function in vivo. C_LIO_LIPALMD mitigates cardiac dysfunction and myocardial injury after repeated isoproterenol insults. C_LIO_LIPALMD stabilizes NEXN, an essential Z-line-associated regulator of the junctional membrane complex and cardiac systolic function. C_LI

molecular biology↗

The ChickenGTEx pilot analysis: a reference of regulatory variants across 28 chicken tissues

Chicken is a valuable model for understanding fundamental biology, vertebrate evolution and diseases, as well as a major source of nutrient-dense and lean-protein-enriched food globally. Although it is the first non-mammalian amniote genome to be sequenced, the chicken genome still lacks a systematic characterization of functional impacts of genetic variants. Here, through integrating 7,015 RNA-Seq and 2,869 whole-genome sequence data, the Chicken Genotype- Tissue Expression (ChickenGTEx) project presents the pilot reference of regulatory variants in 28 chicken tissue transcriptomes, including millions of regulatory effects on primary expression (including protein-coding genes, lncRNA and exon) and post-transcriptional modifications (alternative splicing and 3 untranslated region alternative polyadenylation). We explored the tissue-sharing and context-specificity of these regulatory variants, their underlying molecular mechanisms of action, and their utility in interpreting adaptation and genome-wide associations of 108 chicken complex traits. Finally, we illustrated shared and lineage-specific features of gene regulation between chickens and mammals, and demonstrated how the ChickenGTEx resource can further assist with translating genetic findings across species. One-Sentence SummaryThe ChickenGTEx provides a multi-tissue reference of regulatory variants for chicken genetics and genomics, functional genomics, precision breeding, veterinary medicine, vertebrate evolution and even human biomedicine.

genetics↗

TERT accelerates BRAF mutant-induced thyroid cancer dedifferentiation and progression by regulating ribosome biogenesis

TERT reactivation occurs frequently in human malignancies. While BRAF activating mutation widely existed in cancers at various stages, TERT reactivation mainly occurs in advanced tumors. However, in vivo evidence for TERT role in cancer progression and the underlying mechanism is currently lacking. In this study, we induced TERT and/or BRAF V600E expression in mouse thyroid epithelium. TERT overexpression alone had no evident effect on tumor initiation. BRAFVE expression itself induced mediocre papillary thyroid cancer (PTC). Notably, the co-expression of BRAFVE and TERT resulted in aggressive poorly differentiated thyroid carcinoma (PDTC). Spatial transcriptome revealed that tumors from co-mutant mice were highly heterogeneous and dedifferentiation process significantly correlated with ribosomal pathways. Mechanistically, TERT boosted ribosomal RNA expression and protein synthesis. CX-5461, a rRNA transcription inhibitor, effectively blocked proliferation and induced redifferentiation. Thus, TERT promotes thyroid cancer progression by inducing dedifferentiation, and ribosome biogenesis inhibition represents a potential treatment strategy for TERT-reactivated cancers. Highlights[tpltrtarr] TERT accelerated thyroid cancer dedifferentiation and metastasis in vivo [tpltrtarr]TERT regulated rRNA metabolism and MTORC1/ S6K/RPS6 activities [tpltrtarr]CX-5461 inhibited the progression of TERT-reactivated melanoma and thyroid cancer [tpltrtarr]Inhibition of rRNA induced redifferentiation of advanced thyroid cancer with TERT activation

cancer biology↗

Massively parallel single-cell sequencing of genetic loci in diverse microbial populations

Single cell genetic heterogeneity is ubiquitous in microbial populations and an important aspect of microbial biology. However, we lack a broadly applicable and accessible method to study this heterogeneity at the single cell level. Here, we introduce a simple, robust, and generalizable platform for quantitative and massively parallel single cell sequencing of target genetic loci in microbes using ultrahigh-throughput droplet microfluidics (Droplet Targeted Amplicon Sequencing or DoTA-seq). Using DoTA-seq, we elucidate the highly diverse single cell ON/OFF states of the phase-variable capsule synthesis operons in the prevalent human gut species Bacteroides fragilis. In addition, we quantify the shifts in antibiotic resistance gene abundances in different species in a 25 member human gut microbial community in response to antibiotics. By sequencing tens of thousands of single-cells derived from a human fecal sample, we identify links between plasmid replicons and the taxonomic lineages of their associated hosts. In sum, DoTA-seq is an accessible and broadly applicable tool for profiling single-cell genetic variation in microbiomes.

microbiology↗

RNA m6A and 5hmC regulate monocyte and macrophage gene expression programs

BackgroundRNA modifications are essential for the establishment of cellular identity. Although increasing evidence indicates that RNA modifications regulate the innate immune response, their role in monocyte-to-macrophage differentiation and polarisation is unclear. To date, most studies have focused on m6A, while other RNA modifications, including 5hmC, remain poorly characterised. The interplay between different RNA modifications that may occur in specific cellular contexts remains similarly unexplored. ResultsWe profiled m6A and 5hmC epitranscriptomes, transcriptomes, translatomes and proteomes of monocytes and macrophages at rest and pro- and anti-inflammatory states. We observed that decreased expression of m6A and 5hmC writers, METTL3 and TET-enzymes respectively, facilitated monocyte-to-macrophage differentiation. Despite a global trend of m6A and 5hmC loss during macrophage differentiation, enrichment of m6A and/or 5hmC on specific categories of transcripts essential for macrophage differentiation positively correlated with their expression and translation. m6A and 5hmC mark and are associated with the expression of transcripts with critical functions in pro- and anti-inflammatory macrophages. Notably, we also discovered the coexistence of m6A and 5hmC marking alternatively-spliced isoforms and/or opposing ends of the untranslated regions (UTR) of transcripts with key roles in macrophage biology. In specific examples, RNA 5hmC controls the decay of transcripts independently of m6A. ConclusionsThis study: i) uncovers m6A, 5hmC and their writer enzymes as regulators of monocyte and macrophage gene expression programs and ii) provides a comprehensive dataset to interrogate the role of RNA modifications in a plastic system. Altogether, this work sheds light on the role of RNA modifications as central regulators of effector cells in innate immunity.

molecular biology↗

Single-cell bacterial sequencing of invertible loci reveals promoter inversion rates as a strong determinant of population heterogeneity

Population heterogeneity can promote bacterial fitness in response to unpredictable environmental conditions. Human gut symbiont Bacteroides spp., displays variability in single cell surface architectures by combinatorial regulation of promoter inversions that drive expression of capsular polysaccharides (CPS). Using high-throughput single-cell sequencing, we reveal population heterogeneity generated through combinatorial promoter inversion and show that B. fragilis populations can access diverse CPS promoter states. Combining our data with stochastic computational modeling, we demonstrate that the rates of promoter inversion regulated by a broadly conserved serine recombinase are a major mechanism shaping population heterogeneity. Exploiting control over the expression of the recombinase, we devise a method for creating phase-locked variants and show that populations with different initial compositions converge to a similar steady-state composition over time. Our approach can be used to interrogate single-cell phase variable states of diverse microbes including bacterial pathogens. Summary sentenceHigh-throughput single cell sequencing of phase variation reveals regulation as a major driver of population diversification

systems biology↗

A potent SARS-CoV-2 antibody neutralizes Omicron variant by disassembling the spike trimer

The continuous emergence of novel SARS-CoV-2 variants poses new challenges to the fight against the COVID-19 pandemic. The newly emerging Omicron strain caused serious immune escape and raised unprecedented concern all over the world. The development of antibody targeting conserved and universal epitope is urgently needed. A subset neutralizing antibody(nAbs) against COVID-19 from convalescent patients were isolated in our previous study. Here in this study, we investigated the accommodation of these nAbs to SARS-CoV-2 variants of concerns (VOCs), revealing that IgG 553-49 neutralizes pseudovirus of SARS-CoV-2 Omicron variant. In addition, we determined the cryo-EM structure of SARS-CoV-2 spike complexed with three antibodies targeting different epitopes, including 553-49, 553-15 and 553-60. Notably, 553-49 targets a novel conserved epitope and neutralizes virus by disassembling spike trimers. 553-15, an antibody that neutralizes all the other VOCs except omicron, cross-links two spike trimers to form trimer dimer, demonstrating that 553-15 neutralizes virus by steric hindrance and virion aggregation. These findings suggest the potential to develop 49 and other antibody targeting this highly conserved epitope as promising cocktail therapeutics reagent for COVID-19. ImportanceThe newly emergence of Omicron strain caused higher immune escape, raising unprecedented concerns about the effectiveness of antibody therapies and vaccines. In this study, we identified a SARS-CoV-2 Omicron neutralizing antibody 553-49, which neutralizes Omicron variant by targeting a completely conserved novel epitope. Besides, we revealed that IgG 553-15 neutralizes SARS-CoV-2 by crosslinking virions and 553-60 functions by blocking receptor binding. Comparison of different RBD epitopes revealed that the epitope of 553-49 is hidden in the S trimer and keeps high conservation during SARS-CoV-2 evolution, making 553-49 a promising therapeutics reagent to fight against the emerging Omicron and future variant of SARS-CoV-2.

microbiology↗

Transmembrane protein KIRREL1 regulates Hippo signaling via a feedback loop and represents a potential therapeutic target in YAP/TAZ-active cancers

Dysregulation of the Hippo tumor suppressor pathway and hyperactivation of YAP/TAZ are frequently observed in human cancers and represent promising therapeutic targets. However, strategies targeting the mammalian Hippo pathway are limited due to the lack of a well-established cell surface regulator. By combining protein interactome data and clinical data, we have identified transmembrane protein KIRREL1 as an upstream regulator of the Hippo pathway. KIRREL1 interacts with Hippo pathway components SAV1 and LATS1/2 via its intracellular C-terminal domain and promotes LATS1/2 activation by MST1/2 (Hippo kinases), in turn inhibiting YAP/TAZ activity and target gene expression. Conversely, YAP/TAZ directly induce the expression of KIRREL1 in a TEAD1-4-dependent manner. In mouse liver tumors driven by YAP activation, KIRREL1 protein is robustly induced. Moreover, KIRREL1 expression positively correlates with canonical YAP/TAZ target gene expression in clinical tumor specimens and predicts poor prognosis. Finally, transgenic expression of KIRREL1 effectively blocked tumorigenesis in a mouse intrahepatic cholangiocarcinoma model, suggesting an important role of KIRREL1 in inhibiting cancer development. Together, these findings indicate that KIRREL1 constitutes a negative feedback mechanism regulating the Hippo pathway, and serves as a cell surface marker and potential drug target in cancers with YAP/TAZ dependency.

cancer biology↗

De novo assembly of 20 chickens reveals the undetectable phenomenon for thousands of core genes on sub-telomeric regions

The gene numbers and evolutionary rates of birds were assumed to be much lower than that of mammals, which in sharp contrast to the huge species number and morphological diversity of birds. It is very necessary to construct a complete avian genome and analyze its evolution.We constructed a chicken pan-genome from 20 de novo genome assemblies with high sequencing depth, newly identified 1,335 protein-coding genes and 3,011 long noncoding RNAs. The majority of these novel genes were detected across most individuals of the examined transcriptomes but were accidentally measured in each of the DNA sequencing data regardless of Illumina or PacBio technology. Furthermore, different from previous pan-genome models, most of these novel genes were overrepresented on chromosomal sub-telomeric regions, surrounded with extremely high proportions of tandem repeats, and strongly blocked DNA sequencing. These hidden genes were proved to be shared by all chicken genomes, included many housekeeping genes, and enriched in immune pathways. Comparative genomics revealed the novel genes had three-fold elevated substitution rates than known ones, updating the evolutionary rates of birds. Our study provides a framework for constructing a better chicken genome, which will contribute towards the understanding of avian evolution and improvement of poultry breeding.

genomics↗

Polysaccharide utilization loci in Bacteroides determine population fitness and community-level interactions

Polysaccharide utilization loci (PULs) in the human gut microbiome have critical roles in shaping human health and ecological dynamics. We develop a CRISPR-FnCpf1-RecT genome-editing tool to study 23 PULs in the highly abundant species B. uniformis (BU). We identify the glycan-degrading functions of multiple PULs and elucidate transcriptional coordination between PULs that enables the population to adapt to the loss of PULs. Exploiting a pooled BU mutant barcoding strategy, we demonstrate that the in vitro fitness and the colonization ability of BU in the murine gut is enhanced by deletion of specific PULs and modulated by glycan availability. We show that BU PULs can mediate complex glycan-dependent interactions with butyrate producers that depend on the mechanism of degradation and the butyrate producer glycan utilizing ability. In sum, PULs are major determinants of community dynamics and butyrate production and can provide a selective advantage or disadvantage depending on the nutritional landscape.

synthetic biology↗

BEdeepoff: an in silico tool for off-target prediction of ABE and CBE base editors

Base editors, including adenine base editors (ABEs) and cytosine base editors (CBEs), are valuable tools for introducing point mutations, but they frequently induce unwanted off-target mutations. Here, we performed a high-throughput gRNA-target library screening to measure editing efficiencies at integrated genomic off-targets and obtained datasets of 48,632 and 52,429 off-targets for ABE and CBE, respectively. We used the datasets to train deep learning models, resulting in ABEdeepoff and CBEdeepoff which can predict editing efficiencies at off-targets. These tools are freely accessible via online web server http://www.deephf.com/#/bedeep.

bioinformatics↗