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Du, X.

Publications and source records attributed to Du, X..

At least 55 records · Page 3Linked to original sources

Interfamily co-transfer of sensor and helper NLRs extends immune receptor functionality between angiosperms

Plant nucleotide-binding, leucine-rich repeat (NLR) immune receptors recognize pathogen effectors and activate defense. NLR genes can be non-functional in distantly related plants (restricted taxonomic functionality, RTF). Here, we enable Solanaceae NLR gene function in rice, soybean and Arabidopsis by co-delivering sensor NLR genes with their cognate NRC-type helper NLRs. In soybean protoplasts and in Arabidopsis plants, Solanum americanum Rpi-amr1, Rpi-amr3 and pepper Bs2 sensor NLRs confer cognate effector responsiveness if co-expressed with NRC helper NLRs. Rice carrying pepper Bs2 and NRCs recognizes the conserved effector, AvrBs2, and resists an important pathogen, Xanthomonas oryzae pv. oryzicola for which no resistance gene is available in rice. Rice lines carrying sensor and helper NLR genes otherwise resemble wild-type, with unaltered basal resistance or field fitness. Thus, interfamily co-transfer of sensor and helper NLRs can broaden utility of sensor NLRs, extending the tools available to control diseases of rice, soybean, Brassicas and other crops.

plant biology↗

Temporal Configuration as a New Feature of Sound: Psychological and Neurophysiological Evidence, Cross-species Consistency and Underlying Neuronal Mechanisms

Natural sounds are defined not only by their spectral content but also by their fine temporal structure. Here we show that millisecond-scale temporal configuration--defined by the ordering of inter-click intervals (ICIs) within a click train--behaves as a distinct auditory feature, conserved across species and emerging hierarchically along the auditory pathway. Human listeners reliably discriminated click trains that shared the same average ICI but differed in temporal configuration, and these differences elicited robust mismatch negativity (MMN) responses in an oddball paradigm, indicating automatic cortical deviance detection. Awake rats showed analogous MMN-like ECoG responses to configuration changes, demonstrating cross-species generality. Neuropixels recordings along the inferior colliculus-medial geniculate body-primary auditory cortex (IC-MGB-A1) axis revealed minimal configuration sensitivity in IC, intermediate sensitivity in MGB, and strong stimulus-specific adaptation to temporal configuration in A1. Reversible cooling of auditory cortex reduced configuration sensitivity in MGB, implicating corticothalamic feedback in shaping thalamic representations. Layer-resolved analyses further showed that supragranular A1 neurons carry stronger configuration-specific adaptation than infragranular neurons. These findings identify temporal configuration as a feature-like dimension of sound and delineate a hierarchical, feedback-dependent IC-MGB-A1 circuit architecture for encoding fine temporal structure in the mammalian brain.

neuroscience↗

A signal of temporal integration in the human auditory brain: psychological insights, EEG evidence, and clinical application

Temporal integration, the process by which the auditory system combines sound information over a curtain period to form a coherent auditory object, is essential for coherent auditory perception, yet its neural mechanisms remain underexplored. We use a "transitional click train" paradigm, which concatenates two click trains with slightly differing inter-click intervals (ICIs), to investigate temporal integration in the human cortex. Using a 64-channel electroencephalogram (EEG), we recorded responses from 42 healthy participants exposed to regular and irregular transitional click trains and conducted change detection tasks. Regular transitional click trains elicited significant change responses in the human cortex, indicative of temporal integration, whereas irregular trains did not. These neural responses were modulated by ICI length, ICI contrast, and regularity. Behavioral data mirrored EEG findings, showing enhanced detection for regular conditions compared to irregular conditions and pure tones. Furthermore, variations in change responses were associated with decision-making processes. Temporal continuity was critical, as introducing gaps between click trains diminished both behavioral and neural responses. In clinical assessments, 22 coma patients exhibited diminished or absent change responses, effectively distinguishing them from healthy individuals. Our findings identify distinct neural markers of temporal integration and highlight the potential of transitional click trains for clinical diagnostics.

neuroscience↗

Language model generates cis-regulatory elements across prokaryotes

Deep learning had succeeded in designing Cis-regulatory elements (CREs) for certain species, but necessitated training data derived from experiments. Here, we present Promoter-Factory, a protocol that leverages language models (LM) to design CREs for prokaryotes without experimental prior. Millions of sequences were drawn from thousands of prokaryotic genomes to train a suite of language models, named PromoGen2, and achieved the highest zero-shot promoter strength prediction accuracy among tested LMs. Artificial CREs designed with Promoter-Factory achieved a 100% success rate to express gene in Escherichia coli, Bacillus subtilis, and Bacillus licheniformis. Furthermore, most of the promoters designed targeting Jejubacter sp. L23, a halophilic bacterium without available CREs, were active and successfully drove lycopene overproduction. The generation of 2 million putative promoters across 1,757 prokaryotic genera, along with the Promoter-Factory protocol, will significantly expand the sequence space and facilitate the development of an extensive repertoire of prokaryotic CREs.

bioinformatics↗

Optimizing Genome Editing in Bovine Cells: A Comparative Study of Cas9 Variants and CRISPR Delivery Methods

To assist in the establishment of an efficient CRISPR/Cas9 gene editing workflow in bovine cells, we compared the efficiency of four Streptococcus pyogenes Cas9 (SpCas9) nuclease variants (produced in-house or commercially) and two different Cas9/sgRNA ribonucleoprotein (RNP) delivery methods applied to Madin-Darby bovine kidney (MDBK) cells (Bos taurus). We targeted three genes for simple sequence deletion or modification via a single-stranded oligodeoxynucleotide donor template: the testis-determining gene Sry (sex-determining region on Y chromosome), germ cell-specific gene Nanos2 (nanos C2HC-type zinc finger 2) and PRLR (prolactin receptor). RNPs and donor templates were delivered into cells via lipofectamine CRISPRMAX transfection or Neon electroporation. The efficiency of gene editing was determined by target-specific PCR genotyping, real-time PCR assays and next generation sequencing analyses. When targeting Sry, the commercial Alt-R High-Fidelity (HiFi) SpCas9 nuclease exhibited the highest deletion efficiency, followed by the in-house generated Sniper2L, HiFi SpCas9 and wild-type SpCas9. Notably, for PRLR and Nanos2, Sniper2L induced comparable editing outcomes to Alt-R HiFi SpCas9. The two delivery methods, lipofectamine CRISPRMAX transfection and Neon electroporation, demonstrated similar efficiency (60% to 83%) in producing indels in all three target genes. However, Neon electroporation (5.5% to 11%) was superior to CRISPRMAX lipofection (1.5% to 4.8%) at inducing target-specific sequence knock-ins. Strategies to inhibit NHEJ repair and/or enhance HDR may be necessary to improve HDR efficiency in these bovine cells. These findings provide valuable insights for improving gene editing outcomes in bovines and may assist in accelerating the widespread application of genome editing technology in large animals.

molecular biology↗

Phage CRISPR-like regulatory RNAs silence bacterial adaptive and innate immunity

CRISPR RNAs (crRNAs) encoded by CRISPR arrays direct Cas nucleases against viruses. Some CRISPR-Cas loci also contain mini-arrays encoding crRNA-like RNAs (crlRNAs), which modulate transcription of cas or associated toxin genes that safeguard CRISPR-Cas activity. Here, we report that phages hijack these host crlRNA regulatory circuits to suppress bacterial immunity. Viral crlRNAs compete with host crRNAs for Cas protein binding and reprogram Cas proteins to silence their own expression or suppress transcription of CRISPR-safeguarding toxins. These anti-defense crlRNAs are found across diverse phages and plasmids, frequently organized into multiplexed transcriptional units resembling CRISPR arrays, and often synergize with co-encoded anti-CRISPR proteins to disable hierarchical host immune responses. Furthermore, we demonstrate that these compact viral crlRNA architectures can be harnessed for efficient mammalian genome editing. Our findings uncover widespread viral hijacking of host Cas proteins via crlRNAs, highlighting the recurrent exaptation of CRISPR-Cas regulatory functions to counter multilayered bacterial immune defenses.

microbiology↗

Integrating various Experimental Information to Assist Protein Complex Structure Prediction by GRASP

Protein complex structures are essential for understanding of biological activities and drug development. Improving complex structure prediction accuracy of AI models for cases such as antigen-antibody complexes is expected to further enhance their applicability. Meanwhile, a large variety of experimental methods are used to provide structural insights for protein complexes, with only sparse or approximate knowledge obtained. A general tool is needed to integrate AI models with limited experimental information for high-throughput and accurate protein complex structure prediction. To efficiently and flexibly incorporate the different forms of experimental information, we introduce here GRASP. GRASP outperforms existing tools in handling both simulated and real-world experimental restraints including those obtained from XL, CL, CSP, and DMS. As an example, GRASP excels in predicting antigen-antibody complex structures, even surpassing AF3 when utilizing experimental DMS and CL restraints. In addition to accelerating the restrained modeling process, its ability to integrate multiple forms of restraints makes it capable of integrative modeling. We also showcase its potential in modeling protein structural interactome in the near-cellular condition based on large-scale in vivo XL data for mitchondria.

bioinformatics↗

Dynamic epigenomic landscape of carbon-concentrating mechanisms in the model industrial oleaginous microalga Nannochloropsis oceanica

Despite their ecological and physiological significance, how carbon-concentrating mechanisms (CCM) are regulated in microalgae remains elusive. Here in the model industrial microalga Nannochloropsis oceanica, we uncovered an epigenetic regulatory mechanism for CCM via comprehensive, multi-dimensional epigenomic analyses. Our integrated study reveals the complex interplay among histone modifications, dynamic nucleosome positioning, and 3D chromatin structure in regulating gene expression during low CO2 adaptation, despite minimal DNA methylation. Histone modifications, including lysine acetylation (H3K9ac and H3K27ac), crotonylation (Kcr), and methylation (H3K4me2), were associated with active chromatin states. Significantly altered ChIP-Seq peaks were linked to 43.1% of the differentially expressed genes (DEGs). Notably, H3K4me2 exhibited a distinct dual-peak profile around the transcription start site (TSS), which is unique among microalgae and plants. Chromatin compartment dynamics were correlated with gene expression and histone modifications, particularly H3K4me2, while differentially positioned nucleosomes were associated with key CCM-related genes and transcription factors. To further elucidate the role of H3K4me2, we knocked out its methyltransferase, resulting in genome-wide H3K4me2 peak shifts, slower growth, and reduced photosynthesis. These changes were accompanied by differential expression of key genes of NoHINT and NoPMA2, whose subsequent deletion and overexpression revealed their subtle yet significant impacts on growth and photosynthetic efficiency under low CO2 conditions, with NoHINT regulating growth and NoPMA2 influencing photosynthesis. Finally, we proposed a comprehensive model for epigenetic regulation of CCM in N. oceanica, which established a foundation for enhancing microalgal productivity through targeted epigenetic modifications. HighlightsO_LIMulti-layered epigenetic modifications contribute to the regulation of CCM and its adaptation to low CO2 in N. oceanica. C_LIO_LIThe histone modification H3K4me2 regulates the growth and photosynthesis of N. oceanica under low CO2 conditions. C_LIO_LIH3K4me2 targets NoHINT and NoPMA2 in N. oceanica, with NoHINT influencing growth dynamics and NoPMA2 modulating photosynthetic efficiency under low CO2 conditions. C_LI

genomics↗

Modeling the antigenic evolution of seasonal influenza viruses with PREDAC for vaccine strain selection in the season of 2025

IntroductionThe antigenic evolution of seasonal influenza viruses have been reported to be discontinuous as clusters. Timely identification of antigenic clusters could help for influenza virus vaccine strain selections. MethodsHere, we revealed the antigenic evolution of seasonal influenza viruses, including A(H3N2), A(H1N1pdm) and B-Victoria, using our previously developed PREDAC methods, and identified antigenic clusters of seasonal influenza viruses based on existing HA protein sequences in GISAID database. ResultsDuring the last six months (2024.2[~]2024.7), for the influenza A(H3N2) virus, the antigenic clusters DA21 (A/Darwin/6/2021-like and A/Massachusetts/18/2022-like) continuously dominated and nearly all viruses are antigenic similar to the current vaccine strain A/Massachusetts/18/2022; for the influenza A(H1N1pdm) virus, the antigenic cluster SY21 (A/Sydney/5/2021-like and A/Victoria/4897/2022-like) dominated and nearly all viruses are antigenic similar to the current vaccine strain A/Victoria/4897/2022; for the influenza B-Victoria, antigenic clusters AU21 (B/Austria/1359417/2021-like) dominated and nearly all viruses are antigenic similar to the current vaccine strain B/Austria/1359417/2021. ConclusionThe analysis suggests that there is no need to update the vaccine strains in the flu season of 2025 on the aspect of antigenicity.

microbiology↗

PI(4)P recruits CIDE proteins to promote the formation of unilocular lipids droplets

Lipid droplets (LDs) are evolutionarily conserved organelles that play important roles in metabolism. Each LD is enclosed by a monolayer of phospholipids, distinct from bilayer membranes. The composition of LD surface phospholipids and their impact on LD growth and function remain to be clearly defined. Phosphoinositides mark cellular organelles and regulate cell signalling and organellar function. Here, we demonstrate that PI(4)P decorates a subset of LDs to recruit and activate the CIDE proteins. Enhanced expression of ORP2 and ORP5, LD-associated lipid transfer proteins that remove PI(4)P from LDs, abolished the localization and function of CIDE proteins. Blocking the synthesis of PI(4)P on LD surface via knocking down PI4K2A also impaired the localization and function of CIDE proteins. In adipocytes, depleting PI(4)P dramatically reduced the size of LDs, as well as adipose tissue mass. In severe steatotic liver, depleting PI(4)P reduced LD accumulation. Our results thus identify a key function of LD surface PI(4)P under physiological conditions and unveil how CIDE proteins are recruited to LDs.

cell biology↗

Efficient generation of CAR NK cells from human umbilical cord blood CD34+ stem and progenitors for democratizing affordable immunotherapy

Chimeric antigen receptor (CAR) natural killer cells (CAR NK) cells, leveraging safety and not requiring HLA match in adoptive infusion, have emerged as promising alternative cells to CAR-T cells for immunotherapies. High and multiple doses of CAR NK cell infusions are essential to maintain therapeutic efficacy in clinical trials. This requires efficient methods for generating large-scale CAR NK cells and significantly reducing CAR engineering costs. In this study, we develop a three-step strategy to generate highly high yields of induced NK (iNK) and CAR iNK cells from human umbilical cord blood CD34+ hematopoietic stem and progenitor cells (CD34+ HSPCs). Starting from a single umbilical cord blood CD34+ HSPC, our reliable method efficiently produces 14-83 million mature iNK cells or 7-32 million CAR iNK cells with high expression levels of CD16 and zero T cell contaminations. Introducing CAR expression elements at the HSPC level reduces the quantities of CAR pseudoviruses to 1 / 140.000 - 1 / 600,000 compared to engineering CARs in mature NK cells. The iNK and CAR iNK cells, including fresh cells and thawed cells from cryopreserved conditions, demonstrate remarkable tumoricidal activities against various human cancer cells and significantly prolong the survival of human tumor-bearing animals. The high yields of CAR NK cells and negligible costs of CAR engineering of our method support the broad applications of CAR NK cells for treating cancer patients.

cell biology↗

Generation of High-fidelity Blastocyst-like Structures from Porcine Expanded Pluripotent stem cell via Chemically inducing cell plasticity

Understanding the mechanisms of blastocyst formation and implantation is crucial for advancing farm animal reproduction. However, research in this area is often hindered by the limited availability of embryos. In this study, we developed an efficient method to generate blastocyst-like structures (termed blastoids) from porcine expanded pluripotent stem cells (pEPSCs) through chemical induction with an efficiency up to 80%. These porcine blastoids closely resemble natural blastocysts in terms of morphology, cell composition, and single-cell transcriptomes. The tissue structures of the blastoids developed over time in culture, resembling the tissue morphology of gastrulation-stage embryos. This innovative approach not only provides a robust in vitro model for studying early embryogenesis in pigs but also holds the potential for improving reproductive efficiency and understanding the developmental processes of large farm animal species. The development of porcine blastoids represents a significant advancement in regenerative medicine and developmental biology.

cell biology↗

Beyond Auditory Relay: Dissecting the Inferior Colliculus's Role in Sensory Prediction, Cognitive Decision-Making, and Reward Prediction

The Inferior Colliculus (IC) has traditionally been regarded as an important relay in the auditory pathway, primarily involved in relaying auditory information from the brainstem to the thalamus. However, this study uncovers the multifaceted role of the IC in bridging auditory processing, sensory prediction, and reward prediction. Through extracellular recordings in monkeys engaged in a sound duration-based deviation detection task, we observed a "climbing effect" in neuronal firing rates, indicative of an enhanced response over sound sequences linked to sensory prediction rather than reward anticipation. Moreover, our findings demonstrate reward prediction errors within the IC, highlighting its complex integration in auditory and reward processing. Further analysis revealed a direct correlation between IC neuronal activity and behavioral choices, suggesting its involvement in decision-making processes. This research highlights a more complex role for the IC than traditionally understood, showcasing its integral role in cognitive and sensory processing and emphasizing its importance in integrated brain functions.

neuroscience↗

FLASH radiotherapy using high-energy X-rays: validation of the FLASH effect triggered by a compact single high-energy X-ray source device

PurposeThis preclinical study aimed to verify the FLASH effect of compact single high-energy X-ray source (CHEXs) and to explore whether three irradiations with single-gantry rotation two 30 s pauses can generate FLASH effect in mice. Materials and methodsThe absolute dose and pulsed beam of the CHEXs were measured using an EBTXD radiochromic film and fast current transformer. Healthy C57BL/6J female mice and a subcutaneous tumor model were irradiated under different conditions: sham (control), FLASH-RT (FLASH1: delivering the total dose in 1 fraction; FLASH3: delivering the total dose with two 30 second pauses to simulate a three-field delivery where the gantry rotation is occurring within 30 seconds), and conventional dose rate radiotherapy (CONV-RT). Various total doses were administered to the corresponding normal tissues (whole thorax, 30 Gy; whole abdomen, 12 Gy; and skin, 36 Gy) and tumors (CT26, 16.5 Gy; and LLC, 18 Gy). Survival status, normal tissue damage, and tumor growth suppression were recorded in each group. ResultsThe average dose rate of the CHEXs exceeded 40 Gy/s. For whole-thorax and skin irradiation, both FLASH1 and FLASH3 demonstrated protective effects. For whole-abdomen irradiation, FLASH1 exhibited a superior protective effect. No significant differences in tumor growth responses were observed between the FLASH1, FLASH3, and CONV-RT groups (P>0.05). ConclusionThis study confirmed that the FLASH effect could be triggered using CHEXs FLASH radiotherapy, and demonstrated that three irradiations with single gantry rotation two 30 s pauses can trigger the FLASH effect, indicating the potential benefit of CHEXs 3D conformal radiotherapy. Our findings indicate that further clinical trials on CHEXs are warranted.

cancer biology↗

Biophysical Modeling and Experimental Analysis of the Dynamics of C. elegans Body-Wall Muscle Cells

This study combines experimental techniques and mathematical modeling to investigate the dynamics of C. elegans body-wall muscle cells. Specifically, by conducting voltage clamp and mutant experiments, we identify key ion channels, particularly the L-type voltage-gated calcium channel (EGL-19) and potassium channels (SHK-1, SLO-2), which are crucial for generating action potentials. We develop Hodgkin-Huxley-based models for these channels and integrate them to capture the cells electrical activity. To ensure the model accurately reflects cellular responses under depolarizing currents, we develop a parallel simulation-based inference method for determining the models free parameters. This method performs rapid parallel sampling across high-dimensional parameter spaces, fitting the model to the responses of muscle cells to specific stimuli and yielding accurate parameter estimates. We validate our model by comparing its predictions against cellular responses to various current stimuli in experiments and show that our approach effectively determines suitable parameters for accurately modeling the dynamics in mutant cases. Additionally, we discover an optimal response frequency in body-wall muscle cells, which corresponds to a burst firing mode rather than regular firing mode. Our work provides the first experimentally constrained and biophysically detailed muscle cell model of C. elegans, and our analytical framework combined with robust and efficient parametric estimation method can be extended to model construction in other species. Author summaryDespite the availability of many biophysical neuron models of C. elegans, a biologically detailed model of its muscle cell remains lacking, which hampers an integrated understanding of the motion control process. We conduct voltage clamp and mutant experiments to identify ion channels that influence the dynamics of body-wall muscle cells. Using these data, we establish Hodgkin-Huxley-based models for these ion channels and integrate them to simulate the electrical activity of the muscle cells. To determine the free parameters of the model, we develop a simulation-based inference method with parallel sampling that aligns the model with the muscle cells responses to specific stimuli. Our method allows for swift parallel sampling of parameters in high dimensions, facilitating efficient and accurate parameter estimation. To validate the effectiveness of the determined parameters, we verify the cells responses under different current stimuli in wild type and mutant cases. Furthermore, we investigate the optimal response frequency of body-wall muscle cells and find that it exhibits a frequency consistent with burst firing mode rather than regular firing mode. Our research introduces the first experimentally validated and biophysically detailed model of muscle cells in C. elegans. Additionally, our modeling and simulation framework for efficient parametric estimation in high-dimensional dynamical systems can be extended to model constructions in other scenarios.

neuroscience↗

Dihydromyricetin alleviated the damage of hypoxia-induced mouse neurons by reducing ROS levels and inhibiting the expression of PAR and gammaH2AX

ObjectiveTo investigate the effect of dihydromyricetin on hypoxia-induced neurons, to understand the effect of dihydromyricetin on hypoxic-ischemic encephalopathy (HIE). MethodsCortical neurons were isolated from C57BL/6j mice (24 hour-year old), cultured, and subjected to 4h hypoxia and 20h reoxygenation to mimic the neonatal hypoxic-ischemic encephalopathy. After dihydromyricetin (20mol/L) treatment of hypoxia-induced neurons for 2h, CCK-8 assay was used to analyze the neuronal viability, Hoechst33342/PI double staining assay was used to analyze the neuronal death, Western blotting was used to analyze the expression of Poly ADP-ribose (PAR) polymer protein and {gamma}H2AX, comet assay was used to detect DNA damage, immunofluorescence staining was used to observe the nuclear translocation of apoptosis inducing factor, and 2,7-dichlorodihydrofluorescein diacetate was used to detect the expression of reactive oxygen species (ROS). ResultsCompared with the control groups, hypoxia-treated neurons exhibited significantly lower activity, higher neuronal death rate and the high expressions of PAR and {gamma}H2AX, hypoxia could also induce AIF nuclear translocation, increase tail DNA content and tail length, increase the expression of ROS in neurons; after dihydromyricetin treatment, neuronal activity were significantly increased, neuronal death rate, ROS levels, and the expressions of PAR and {gamma}H2AX were also decreased, AIF nuclear translocation was inhibited, the tail DNA content and tail length were also decreased. ConclusionDihydromyricetin could alleviate the damage of hypoxia-induced neurons through decreasing the levels of ROS and inhibiting the expressions of PAR and {gamma}H2AX, suggesting that dihydromyricetin may have the protective effect on HIE.

neuroscience↗

An applicable and efficient retrograde monosynaptic circuit mapping tool for larval zebrafish

The larval zebrafish is a vertebrate model for in vivo monitoring and manipulation of whole-brain neuronal activity. Tracing its neural circuits remains challenging. Here, we report an applicable methodology tailored for larval zebrafish to achieve efficient retrograde trans-monosynaptic tracing from genetically defined neurons via EnvA-pseudotyped glycoprotein-deleted rabies viruses. By combinatorially optimizing multiple factors involved, we identified the CVS strain trans-complemented with advanced expression of N2cG at 36 {degrees}C as the optimal combination. It yielded a tracing efficiency of up to 20 inputs per starter cell. Its low cytotoxicity enabled the viable labeling and calcium imaging of infected neurons 10 days post-infection, spanning larval ages commonly used for functional examination. Cre-dependent labeling was further developed to enable cell-type-specific input tracing and circuit reconstruction. We mapped cerebellar circuits and uncovered the ipsilateral preference and subtype specificity of granule cell-to-Purkinje cell connections. Our method offers an efficient way for tracing neural circuits in larval zebrafish.

neuroscience↗

Design nonrepetitive and diverse activity single-guide RNA by deep learning

Multiplex and precise control of the gene expression based on CRISPR/Cas9 is important to metabolic regulation in synthetic biology. However, employing single guide RNAs (sgRNAs) that possess repetitive DNA sequences and exhibit uniform activity could detrimentally affect the editing process, undermining both its stability and regulatory potential. In this study, we developed a deep generative model based on a decoder-only Transformer architecture (sgRNAGen) for the de novo generation of a series of nonrepetitive and diverse sgRNAs with activity. To assess the quality of sgRNAs generated by sgRNAGen, we evaluated their activity by targeting essential genes, with the results indicating that 98% of the generated sgRNAs were active in Bacillus subtilis. The generated sgRNAs were further validated for applications in single-gene editing, large fragment knockouts, and multiplex editing. Notably, the efficiency of knocking out long fragments up to 169.5 kb reached 100%, and targeting multiple sites allowed for the creation of strains with various combinations of mutations in a single editing. Furthermore, we developed a CRISPRi system utilizing the designed sgRNAs to regulate gene expression with desired strength and high precision. SgRNAGen offers a method for devising nonrepetitive and diverse activity sgRNAs, enhancing metabolic control and advancing applications within synthetic biology. TOC O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=112 SRC="FIGDIR/small/596019v1_ufig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@f68faaorg.highwire.dtl.DTLVardef@151f5e2org.highwire.dtl.DTLVardef@1e5cb28org.highwire.dtl.DTLVardef@17cd3f8_HPS_FORMAT_FIGEXP M_FIG C_FIG

synthetic biology↗