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Glucose-responsive probiotics for glycaemic modulation in mice and monkeys.

Sustained and controlled delivery of glucose-lowering agents using engineered designer cells is recognized as an effective strategy for diabetes therapy1. However, current technologies rely on external signal control or have been programmed into mammalian cells using synthetic gene networks, which pose safety concerns arising from transplantation2,3. Here we developed an engineered oral-deliverable glucose-sensing and functional response probiotic living drug for 'sense-and-respond'-based control of diabetic blood glucose. We created a glucose sensor based on a synthetic gene circuit that incorporates the glucose-responsive transcriptional regulator HexR, coupled with a synthetic promoter. Upon oral administration of the engineered probiotics carrying the sensor, the cells reside temporarily in the intestine and regulate the expression of therapeutic transgenes in response to glucose levels that exceed the normal threshold. We show efficacy from the engineered probiotics for glycaemic control in multiple diabetic mouse and non-human primate models, demonstrating that long-term oral administration drives clear improvements in lipid profiles, while also attenuating development of multiple diabetic complications. Our probiotics-based living drug enables therapeutic dosing in response to real-time blood glucose levels, providing a programmable, orally deliverable sense-and-respond platform for metabolic therapy without transplantation.

Animals

Hormone priming and metabolic engineering of phytohormone crosstalk in rice under combined biotic and abiotic stresses: a multi-omics perspective for climate-resilient crop development.

Rice (Oryza sativa L.) is the caloric backbone for more than half of humanity, yet it remains one of the most vulnerable crops to the simultaneous biotic and abiotic stresses exacerbated by climate change. Phytohormone priming and the complex crosstalk networks governed by transcription factor hubs like WRKY, MYB, and NAC serve as the central adaptive mechanism for stress resilience. This review synthesizes how multi-omics integration, including spatial and single-cell transcriptomics, is resolving the molecular architecture of hormonal priming and epigenetic stress memory. We critically evaluate advanced metabolic engineering and genome-editing strategies such as CRISPR-Cas9, base/prime editing, and synthetic gene circuits that enable precision modifications to decouple stress tolerance from historical yield penalties. Furthermore, we discuss the emerging roles of microbiome-assisted priming via synthetic consortia and the application of artificial intelligence and digital twins (continuously updated computational models of crop physiology) for predictive stress management. By integrating these diverse technological pillars, we propose a systems-level roadmap for developing climate-resilient rice cultivars capable of maintaining yield stability across a volatile combinatorial stress landscape. This synthesis provides a framework for translating mechanistic hormonal insights into field-applicable cultivars to ensure global food security.

CRISPR

Recent advances in molecular mechanisms to improve the efficacy of CAR-T cell therapy for viral diseases, cancer, and autoimmune diseases.

Chimeric antigen receptor (CAR)-T cell therapy has transformed the treatment of hematological malignancies, yet its broader application to solid tumors, chronic viral infections, and autoimmune diseases remains constrained by antigen heterogeneity, immunosuppressive tissue microenvironments, T-cell exhaustion, limited persistence, and treatment-associated toxicities. These challenges have shifted the field from optimizing individual receptor constructs toward engineering CAR-T cells as programmable immune systems capable of adapting to diverse disease contexts. This review synthesizes recent advances in molecular engineering strategies that enhance CAR-T cell function beyond conventional receptor design. We discuss how receptor engineering, genome editing, transcriptional and epigenetic regulation, metabolic reprogramming, synthetic gene circuits, and safety-control platforms collectively reshape CAR-T cell fate, persistence, and therapeutic efficacy. Rather than functioning independently, these engineering strategies are increasingly integrated to generate context-specific cellular therapies capable of adapting to diverse disease environments, including cancer, autoimmune diseases, and chronic viral infections. We also highlight the potential for translation into clinical practice or clinical translation and discuss the major challenges associated with clinical implementation. Next-generation CAR-T therapies will increasingly integrate molecular engineering strategies or will rely on molecular engineering strategies to integrate antigen recognition, cellular fitness, immune regulation, and longevity rather than simply maximizing cytotoxic activity. Recent advances in programmable cellular engineering coupled with rigorous clinical evaluation as well as scalable manufacturing technologies or scalable manufacturing platforms in the treatment of other diseases beyond oncology will facilitate the development of safer, more durable, and broadly applicable cellular therapies.

Humans

A voyage of reprogrammable metabolic bioengineering reshapes plant defense: from editing tools to synthetic systems.

Metabolic bioengineering has emerged as a transformative approach for reshaping plant defense by targeting intrinsic biosynthetic pathways to enhance immunity in modern agriculture. Moving beyond proof-of-concept metabolomics to broad-spectrum programmable pathway engineering addresses gaps in plant rational design and optimizes resilience in response to diverse environmental cues. This review aims to comprehensively highlight the transition of innovative approaches to phenolics, alkaloids, flavonoids, terpenoids, and benzoxazinoids, inferring adaptive reprogramming that mediates the growth-defense balance and functions as molecular sentinels in plants. Furthermore, decoding the volatile metabolome reveals a dynamic signaling interface that influences defense responses and stress-induced plant-microbe interactions, with the shikimate, jasmonate, and salicylate pathways functioning as central hubs for microbial deterrence and priming immune memory. Recent developments in multi-scalar genome-editing strategies, including CRISPR-driven combinatorial edits, enzyme orthogonalization, fluxomics, and spatially resolved multi-omics, reconfigure central and specialized metabolic fluxes toward improved defense function and regulation. Additionally, emerging tools, such as WUSCHEL2 and BABY BOOM transcriptional modules, and artificial engineering strategies integrating deep learning model-driven predictions facilitate rapid development of synthetic genetic circuits and support a predictive engineering of plants. Moreover, Mass spectrometry imaging (MSI) in spatial metabolomics enables to obtain structures and locations of unidentified endogenous metabolites within cells and tissues. Overall, this review emphasizes a diverse array of primary and secondary metabolites, spanning molecular concepts to recent advances in plant immune mechanisms. It also illustrates new frontiers in programmable metabolic engineering that accelerate the understanding of plant-microbe-metabolite cross-talks, offering strategies to improve plant resistance and advance sustainable agricultural solutions.

metabolic bioengineering

Gene regulation technologies for gene and cell therapy.

Gene therapy stands at the forefront of medical innovation, offering unique potential to treat the underlying causes of genetic disorders and broadly enable regenerative medicine. However, unregulated production of therapeutic genes can lead to decreased clinical utility due to various complications. Thus, many technologies for controlled gene expression are under development, including regulated transgenes, modulation of endogenous genes to leverage native biological regulation, mapping and repurposing of transcriptional regulatory networks, and engineered systems that dynamically react to cell state changes. Transformative therapies enabled by advances in tissue-specific promoters, inducible systems, and targeted delivery have already entered clinical testing and demonstrated significantly improved specificity and efficacy. This review highlights next-generation technologies under development to expand the reach of gene therapies by enabling precise modulation of gene expression. These technologies, including epigenome editing, antisense oligonucleotides, RNA editing, transcription factor-mediated reprogramming, and synthetic genetic circuits, have the potential to provide powerful control over cellular functions. Despite these remarkable achievements, challenges remain in optimizing delivery, minimizing off-target effects, and addressing regulatory hurdles. However, the ongoing integration of biological insights with engineering innovations promises to expand the potential for gene therapy, offering hope for treating not only rare genetic disorders but also complex multifactorial diseases.

Humans

Bimodality in E. coli gene expression: Sources and robustness to genome-wide stresses.

Bacteria evolved genes whose single-cell distributions of expression levels are broad, or even bimodal. Evidence suggests that they might enhance phenotypic diversity for coping with fluctuating environments. We identified seven genes in E. coli with bimodal (low and high) single-cell expression levels under standard growth conditions and studied how their dynamics are modified by environmental and antibiotic stresses known to target gene expression. We found that all genes lose bimodality under some, but not under all, stresses. Also, bimodality can reemerge upon cells returning to standard conditions, which suggests that the genes can switch often between high and low expression rates. As such, these genes could become valuable components of future multi-stable synthetic circuits. Next, we proposed models of bimodal transcription dynamics with realistic parameter values, able to mimic the outcome of the perturbations studied. We explored several models' tunability and boundaries of parameter values, beyond which it shifts to unimodal dynamics. From the model results, we predict that bimodality is robust, and yet tunable, not only by RNA and protein degradation rates, but also by the fraction of time that promoters remain unavailable for new transcription events. Finally, we show evidence that, although the empirical expression levels are influenced by many factors, the bimodality emerges during transcription initiation, at the promoter regions and, thus, may be evolvable and adaptable.

Escherichia coli

Coarse-grained resource allocation modeling for decoding and rewiring microbial metabolism.

Microbial metabolism is a complex, emergent system driven by the coordinated interplay of intricate and dynamic molecular processes. To elucidate cellular behavior and enable biotechnological applications, quantitative models that address the inherent complexity of metabolism have been developed from a resource allocation perspective. Here, we synthesize recent advances in coarse-grained resource allocation frameworks and their applications in understanding microbial physiology and guiding gene circuit design. These frameworks reveal global regulatory constraints and predict cellular adaptation to nutrient and environmental changes. In addition, they enable the quantification of metabolic costs, the dissection of circuit-host interactions, and the development of strategies for burden mitigation. Collectively, these modeling frameworks provide a powerful platform for uncovering quantitative principles of microbial growth and engineering robust synthetic biological systems.

coarse-grained modeling

Transforming Plant Viruses into Vectors for Next-Generation Agriculture-A Review.

Plant viral vectors have evolved from tools for transient gene expression into a versatile platform for precise genetic intervention, offering a rapid, transgene-free alternative to conventional crop transformation. This review critically assesses their engineering for scalable field application, moving beyond foundational techniques like virus-induced gene silencing (VIGS). We highlight how advanced vector design, including deconstructed genomes and synthetic regulatory circuits enhances cargo capacity, specificity, and biosafety. The integration of viral delivery with CRISPR-Cas systems has unlocked virus-induced genome editing (VIGE), base editing, and prime editing, enabling heritable trait modification without tissue culture. However, the transition from proof-of-concept in model plants to robust field technology hinges on overcoming critical bottlenecks: expanding host range through chimeric vectors, ensuring environmental containment, and developing scalable delivery methods such as nano-formulations or adjusted agroinfiltration protocols. We evaluate these delivery routes and emerging synergies with nanobiotechnology for targeted and efficient applications. While challenges in regulation, public perception, and large-scale production persist, the strategic engineering of viral vectors for stability, specificity, and safety positions them as a transformative, next-generation biotechnological input for achieving sustainable crop improvement and protection under changing climatic conditions.

Plant Viruses

Biological Parts in Yeast Synthetic Biology: From Regulatory Elements to Predictive Design Platforms.

Yeasts, particularly Saccharomyces cerevisiae, are important eukaryotic chassis for synthetic biology because of their tractable genetics, versatile toolkits, and broad utility in metabolic engineering and functional genomics. Progress in this field has been driven by biological parts that enable programmable control of gene expression and cellular behavior. Early efforts focused mainly on promoters, terminators, and other regulatory elements for tuning individual genes. However, as engineering expanded to multigene pathways, genetic circuits, and dynamic regulatory systems, the limits of part-centric design became clear. Part performance is often shaped by genomic context, chromatin state, host physiology, and interactions with other components, which restricts modularity and predictability. In response, yeast synthetic biology is shifting toward integrated design frameworks combining multilayer regulation, standardized assembly, automated experimentation, and computational modeling. This review provides an integrated perspective on the evolution of biological parts across DNA-, RNA-, and protein-level regulation, connecting these advances with assembly frameworks, biofoundries, and machine learning to trace the trajectory from part-centric engineering toward predictive, system-level design in yeast synthetic biology.

Biofoundry

Beyond the salt barrier: CRISPR-mediated DNA reprogramming to uncouple yield from tolerance in Rice: A review.

Rice (Oryza sativa L.) feeds half of humanity, yet its cultivation is increasingly threatened by soil salinization, which now affects 1.4 billion hectares globally. Decades of breeding and engineering have focused on Na+ exclusion, principally through the Saltol QTL and the xylem-unloading transporter OsHKT1;5, yet this strategy has reached a physiological ceiling. Excluder genotypes survive salinity but fail to fill grain, because the ATP-intensive cost of continuous ion extrusion starves reproductive sinks, while ABA-mediated stomatal closure imposes chronic carbon limitation. The resulting "survival-yield gap" exposes a fundamental flaw in single-trait approaches to a polygenic stress. In this review, we argue that durable, yield-stable salt tolerance requires a coordinated systems-level intervention spanning five mechanistic tiers: (i) CRISPR/Cas9-mediated removal of negative regulatory brakes (OsRR22, RST1, PC1) that suppress plant's latent stress-adaptive capacity; (ii) reinforcement of actin-myosin cytoskeletal transport to sustain SOS1, NHX1, and HKT1;5 delivery under ionic stress; (iii) importation of halophyte design principles from Oryza coarctata, including salt gland architecture and superior Na+ compartmentalization; (iv) recalibration of the ROS-photosynthesis axis via the DHHC09-STRK1-CatC molecular switch and stomatal density engineering; and (v) pyramiding these modules into a "Salt-Shield Rice" genotype through multiplex editing, marker-assisted introgression, speed breeding, and genomic selection. We propose a phased ten-year roadmap that integrates synthetic biology circuit design with conventional breeding to deliver field-ready, multi-module varieties with greater than 70% yield stability at 8-10 dS m-1. This remains an aspirational design target rather than a demonstrated outcome, as three of the five tiers-halophyte-derived structural traits, cytoskeletal reinforcement, and full multi-module pyramiding-remain unvalidated in rice.

CRISPR/Cas9

Programmable promoter editing for precise control of transgene expression.

Subtle changes in gene expression direct cells to distinct cellular states. Identifying and controlling dose-dependent transgenes require tools for precisely titrating expression. Here, we develop a highly modular, extensible framework called DIAL for building editable promoters that allow for fine-scale, heritable changes in transgene expression. Using DIAL, we increase expression by recombinase-mediated excision of spacers between the binding sites of a synthetic zinc finger transcription factor and the core promoter. By nesting varying numbers and lengths of spacers, DIAL generates a tunable range of unimodal setpoints from a single promoter. Through small-molecule control of transcription factors and recombinases, DIAL supports temporally defined, user-guided control of transgene expression that is extensible to additional transcription factors. Lentiviral delivery of DIAL generates multiple setpoints in primary cells and induced pluripotent stem cells. As promoter editing generates stable states, DIAL setpoints are heritable, facilitating mapping of transgene levels to phenotype and fate in direct conversion to induced motor neurons. The DIAL framework opens opportunities for tailoring transgene expression and improving the predictability and performance of gene circuits across diverse applications.

Promoter Regions, Genetic

Integrated multi-omics analysis reveals a pH-driven metabolic and translational switch in Ureaplasma parvum.

Human ureaplasmas are minimal-genome bacteria and pathobionts of the urogenital tract. They must adapt to fluctuating pH conditions despite the absence of canonical transcriptional regulatory systems. However, the mechanisms underlying these responses remain unclear. This study aimed to construct a system-level model of pH adaptation in this minimal pathogen. We used an integrated multi-omics platform combining proteomics, metabolomics, and RNA modification profiling to construct a system-level model of pH adaptation. The results revealed a bifurcated strategy governed by the differential activation of preexisting, co-regulated functional modules. Under neutral pH conditions (pH 7), Ureaplasma parvum activated energy metabolism and upregulated ATP synthesis while forming a stress-counteracting proteostasis pathway. This may suggest a biological energy state under high stress conditions. Conversely, under acidic stress (pH 5), it activated biosynthesis/translation, showing significant upregulation of ribosomal proteins and accumulation of translation precursors and the polyamine spermidine. This may represent a state of expanded translational capacity. This adaptive switch is accompanied by dynamic reorganization of the epitranscriptome, highlighting the importance of post-transcriptional regulation. This study suggests mechanisms by which minimal organisms achieve adaptive plasticity through sophisticated post-transcriptional and metabolic control, providing a new framework for understanding Ureaplasma physiology and the biology of genome-reduced organisms.IMPORTANCEMinimal bacteria challenge canonical views of cellular regulation. In organisms with radically reduced genomes and sparse transcription factors, how adaptive plasticity is achieved remains a core question. Our study proposes a model in which a simple physicochemical cue-extracellular pH-selects among prewired cellular programs, while post-transcriptional and epitranscriptomic layers fine-tune execution. The findings of this study suggest a multi-omics scheme for how organisms adapt to environmental changes and ensure survival without inducing new circuits or complex transcriptional regulation. Conceptually, it proposes regulation via RNA modifications in processes, such as metabolism, proteostasis, and translation. This framework may be generalizable to other genome-reduced microorganisms. Beyond microbiology, it provides design principles for synthetic biology and offers a mechanistic interpretation of phenotypic tolerance to stress factors. It may encourage the use of pH-linked epitranscriptome signals as measurable indicators of cellular state.

Hydrogen-Ion Concentration