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Wang, D.

Publications and source records attributed to Wang, D..

At least 235 records · Page 13Linked to original sources

Inwardly rectifying potassium channels regulate membrane potential polarization and direction sensing during neutrophil chemotaxis

Potassium channels regulate membrane potential and diverse physiological processes, including cell migration. However, the specific function of the inwardly rectifying potassium channels in immune cell chemotaxis is unknown. Here, we identified that the inwardly rectifying potassium channel Kir7.1 (KCNJ13) maintains the resting membrane potential and is required for directional sensing during neutrophil chemotaxis. Pharmacological or genetic inhibition of Kir7.1 in neutrophils impaired direction sensing toward various chemoattractants without affecting cell polarization in multiple neutrophil models. Using genetically encoded voltage indicators, we observed oscillating depolarization of the membrane potential in protrusions in zebrafish neutrophils, and Kir7.1 is required for polarized depolarization towards the chemokine source. Focal depolarization with optogenetic tools biases pseudopod selection and induces de novo protrusions. Global hyperpolarizing neutrophils stalled cell migration. Furthermore, Kir7.1 regulates GPCR signaling activation. This work adds membrane potential to the intricate feedforward mechanism, coupling the adaptive and excitable network required to steer immune cells in complex tissue environments.

cell biology↗

A single amino acid variant in the variable region I of AAV capsid confers liver detargeting

AAV capsid serotypes isolated from nature have been widely used in gene delivery and gene therapy. Recently, more than 1,000 distinct AAV capsids were identified from human clinical samples by high-throughput, long-read DNA sequencing. In this study, we tap into this broad natural biodiversity of AAV capsids to develop liver-tropic AAV capsids. We initially screened a subset of variants derived from AAV8 (n=159) for packaging efficiency. The high-yielding variants were subjected to a barcoded vector library screen in mice and ferrets for their ability to mediate liver gene transfer. Although no variant surpassed AAV8 for liver targeting, several exhibited a liver detargeting phenotype. Among these, we focused on the N271D variant (AAV8 VP1 numbering), located in the variable region I (VR-1), which has been previously implicated in influencing liver tropism. The liver detargeting phenotype of AAV8.N271D was confirmed by single vector administration in mice. Additionally, we grafted the N271D variant onto AAV9 and MyoAAV capsids (N270D by AAV9 VP1 numbering). The AAV9.N270D and MyoAAV.N270D vectors showed a similar liver-detargeting phenotype, although muscle targeting was moderately reduced. Although we did not identify any capsid variants that outperform AAV8 in liver transduction, this study reinforces the important role of VR-1 in modulating liver tropism and highlights the potential of engineering VR-1 residues to reduce liver gene transfer and associated toxicity observed in several gene therapy studies.

molecular biology↗

Excavating Podocyte-Protective Targets of phloroglucinol-terpene hybrids Utilizing AI Models and Omics Analysis

Lupus nephritis (LN) is a multifactorial autoimmune inflammatory disorder, with podocyte dysfunction or structural abnormalities playing a pivotal role in its pathogenesis. Eucalyptus leaves, traditionally employed in folk medicine, have demonstrated notable efficacy in managing non-infectious inflammations. Eucarbwenstols D (R14) is a novel phloroglucinol-terpene that has been isolated from Eucalyptus robusta. To further refine potential targets, we utilized an AI scoring system and successfully identified the epidermal growth factor receptor (EGFR) as the novel target of R14. This discovery was built upon the foundation of transcriptome and connectivity mapping (CMap) analysis. Molecular docking and molecular dynamics simulations were employed to analyze the interaction between R14 and EGFR, surface plasmon resonance (SPR) and homogeneous time-resolved fluorescence (HTRF) assays were utilized to accurately quantify the binding affinity between R14 and EGFR. Western blot (WB) and immunofluorescence assays were then conducted to explore the downstream signaling pathways initiated by EGFR, specifically the PI3K/AKT/mTOR pathway. These assays demonstrated that R14 modulates the expression of apoptotic proteins Bax and Bcl-2 through this pathway, thereby exerting a protective effect on podocytes from undergoing apoptosis. The modulation of key podocyte proteins, nephrin and podocin, further substantiates this protective effect. Overall, we have applied a novel AI algorithm model that transcends bioinformatics analysis to precise identification of the novel podocyte target of R14. In this study, R14 was identified for the first time as a novel scaffold compound for EGFR inhibition. Moreover, R14 has demonstrated its capacity to inhibit podocyte apoptosis, thereby protecting these critical cells. This discovery establishes a robust theoretical foundation for the use of phloroglucinol-terpene hybrids (PTHs) in the treatment of LN.

cell biology↗

Emergence of cooperation promoted by higher-order strategy updates

Cooperation is fundamental to human societies, and the interaction structure among individuals profoundly shapes its emergence and evolution. In real-world scenarios, cooperation prevails in multi-group (higher-order) populations, beyond just dyadic behaviors. Despite recent studies on group dilemmas in higher-order networks, the exploration of cooperation driven by higher-order strategy updates remains limited due to the intricacy and indivisibility of group-wise interactions. Here we investigate four categories of higher-order mechanisms for strategy updates in public goods games and establish their mathematical conditions for the emergence of cooperation. Such conditions uncover the impact of both higher-order strategy updates and network properties on evolutionary outcomes, notably highlighting the enhancement of cooperation by overlaps between groups. Interestingly, we discover that the group-mutual comparison update - selecting a high-fitness group and then imitating a random individual within this group - can prominently promote cooperation. Our analyses further unveil that, compared to pairwise interactions, higher-order strategy updates generally improve cooperation in most higher-order networks. These findings underscore the pivotal role of higher-order strategy updates in fostering collective cooperation in complex social systems. Author summaryHuman societies often organize and cooperate within social groups, where relatives, friends, neighbors, and colleagues influence behavior at both group and individual levels. Individuals may exhibit biased or neutral attitudes when selecting a neighboring group and a peer within it for imitation or comparison, a process termed as higher-order strategy update. These selection preferences originate from four personality types: aggressive, open-minded, myopic, and passive. This work demonstrates that the open-minded type - indiscriminately imitating a peer within a well-functioning group - significantly promotes cooperation. The mathematical framework proposed in this study deepens the understanding of how decision-making within higher-order structures affects the emergence and spread of cooperative behaviors.

evolutionary biology↗

Deep-learning-based interpolation of longitudinal microbiome data powers biologically informative discovery

The human microbiome is a foundational and dynamic foundation for several health-related functions and disease processes. Advances in microbiome sequencing have enabled the characterization of microbial communities in several niches. Longitudinal microbiome studies further strive to discover clinically informative microbial community trajectories. However, these data are fraught with dropout events, high noise, and irregular sampling that limit and prevent the use of many available longitudinal analysis tools. To address these challenges, we introduce Bidirectional GRU-ODE-Bayes (BGOB), a deep learning framework developed for longitudinal microbiome interpolation. BGOB combines bidirectional information flow and ODE-based continuous modeling to jointly interpolate and smoothen trends across individual participants, providing uniform, denoised time intervals across patients. BGOB enables vastly improved performance in differential abundance testing and time-to-event analysis, and makes possible longitudinal analyses requiring uniformity, such as lead-lag detection and temporal clustering. After interpolation, previously low-powered datasets are able to broadly recapitulate known microbiology and elucidate interacting microbial communities. We highlight several associations between microbial taxa and disease, including novel species associated with Early Childhood Caries and disruption of key healthy gut microbiota in Inflammatory Bowel Disease. The BGOB package is publicly available at https://github.com/Rachel-Lyu/BGOB_n_test.

microbiology↗

Investigating Gene Expression Noise Reduction by MicroRNAs and MiRISC Reinforcement by Self-Feedback Regulation of mRNA Degradation

The microRNA (miRNA) induced silencing complex (miRISC) is the targeting apparatus and arguably the rate-limiting step of the miRNA-mediated regulatory subsystem - a major noise reducing, though metabolically costly, mechanism. Recently, we reported that miRISC channels miRNA-mediated regulatory activity back onto its own mRNAs to form negative self-feedback loops, a noise-reduction technique in engineering and synthetic/systems biology. In this paper, our mathematical modeling predicts that mRNA expression noise exhibits a negative correlation with the degradation rate (Kdeg) and is attenuated by self-feedback control of degradation. We also calculated Kdeg and expression noise of mRNAs detected in a total-RNA single-cell RNA-seq (scRNA-seq) dataset. As predicted, miRNA-targeted mRNAs exhibited higher Kdeg values accompanied by reduced inter-cell expression noise, confirming the operational trade-off between noise suppression and the increased metabolic/energetic costs associated with producing these mRNAs subjected to accelerated degradation and translational inhibition. Moreover, consistent with the Kdeg self-feedback control model, miRISC mRNAs (AGO1/2/3 and TNRC6A/B/C) exhibited further reduced expression noise. In summary, mathematical-modeling and total-RNA scRNA-seq data-analyses provide evidence that negative self-feedback regulation of mRNA degradation reinforces miRISC, the core machinery of the miRNA-mediated noise-reduction subsystem. To our knowledge, this is the first study to concurrently analyze mRNA degradation dynamics and expression noise, and to demonstrate noise reduction by self-feedback regulation of mRNA degradation.

systems biology↗

HKU5 bat merbecoviruses use divergent mechanisms to engage bat and mink ACE2 as entry receptors

Identifying receptors for bat coronaviruses is critical for spillover risk assessment, countermeasure development, and pandemic preparedness. While Middle East respiratory syndrome coronavirus (MERS-CoV) uses DPP4 for entry, the receptors of many MERS-related betacoronaviruses remain unknown. The bat merbecovirus HKU5 was previously shown to have an entry restriction in human cells. Using both pseudotyped and full-length virus, we show that HKU5 uses Pipistrellus abramus bat ACE2 but not human ACE2 or DPP4 as a receptor. Cryo-electron microscopy (cryo-EM) analysis of the virus-receptor complex and structure-guided mutagenesis reveal a spike and ACE2 interaction that is distinct from other ACE2-using coronaviruses. MERS-CoV vaccine sera poorly neutralize HKU5 informing pan-merbecovirus vaccine design. Notably, HKU5 can also engage American mink and stoat ACE2, revealing mustelids as potential intermediate hosts. These findings highlight the versatility of merbecovirus receptor use and underscore the need for continued surveillance of bat and mustelid species.

microbiology↗

Infectome Analysis of Small Mammals in Southern China Reveals Ecological Associations and Emerging Threats from Diverse Pathogens

Small mammals harbor a diverse array of zoonotic pathogens. To date, however, metagenomic surveys of these species have primarily focused on viral diversity, with limited attention paid to bacteria and eukaryotic pathogens. Additionally, the ecological determinants of pathogen diversity within these mammals have not been systematically examined. Herein, we employed a metatranscriptomics approach to survey the pathogen infectome of 2,408 individual samples, representing lung, liver, and gut tissues from 858 animals collected throughout Guangdong province, China, with a study design that accounted for host species, tissue, season, and geographic location. We identified 76 pathogen species, including 29 RNA viruses, 12 DNA viruses, 5 bacteria, and 30 eukaryotic pathogens, 33 of which were newly discovered. Tissue distribution analysis revealed distinct organotropisms, suggesting varied transmission routes, while host distribution analysis showed that each animal carried an average of one pathogen, with 10 pathogens widely distributed among mammalian orders. Our characterization of the geographic and seasonal patterns revealed that pathogen richness was primarily influenced by region, host species, and season, while pathogen composition was largely shaped by host genetic distance. Collectively, these data provide the first comprehensive insight into the dynamics of the pathogen infectome in these key mammalian disease reservoirs, highlighting the major factors driving pathogen diversity and transmission.

microbiology↗

Single-nucleus analysis reveals dysregulated oxidative phosphorylation in Down syndrome basal forebrain at birth

INTRODUCTIONBasal forebrain cholinergic neurons (BFCNs) are integral to learning, attention, and memory, and are prone to degeneration in Down syndrome (DS), Alzheimers disease, and other neurodegenerative diseases. However, the mechanisms that lead to the degeneration of these neurons are not known. METHODSSingle-nucleus gene expression and ATAC sequencing were performed on postmortem human basal forebrain from unaffected control and DS tissue samples at 0-2 years of age (n=4 each). RESULTSSequencing analysis of postmortem human basal forebrain identifies gene expression differences in DS early in life. Genes encoding proteins associated with energy metabolism pathways, specifically oxidative phosphorylation and glycolysis, and genes encoding antioxidant enzymes are upregulated in DS BFCNs. DISCUSSIONMultiomic analyses reveal that energy metabolism may be disrupted in DS BFCNs by birth. Increased oxidative phosphorylation and the accumulation of reactive oxygen species byproducts may be early contributors to DS BFCN neurodegeneration.

neuroscience↗

Rhamnose-mediated modulation of hair follicle growth: insights from chemical genomics

Pursuing compounds capable of stimulating hair follicle growth or regeneration presents a significant challenge in dermatological research. Dermal papilla (DP) cells, which serve as a dynamic niche for hair follicle stem cells, are often used to identify hair growth-promoting agents as a screening model. Here, we integrated human scalp single-cell RNA sequencing data with human DP cells (hDPCs) gene expression profiles to develop a gene panel for assessing hair follicle inductive potential, then applied a high-throughput sequencing-based high-throughput screening (HTS2) method to quantify the gene expressions of hDPCs perturbed by over 2000 small molecules. Notably, rhamnose was identified as a compound that restored the expression of hair-inducing genes in hDPCs. More importantly, the topical application of rhamnose accelerated hair follicle regeneration by promoting hair cycle into the anagen phase. Transcriptome and central carbon metabolism analyses revealed that rhamnose induced glucose metabolism remodeling favoring glycolysis in mice. A similar phenotype was also observed in rhamnose-treated hDPCs, as demonstrated by glycolysis and mitochondrial stress tests. The present study introduces a novel methodology for evaluating hair-inducing agents and provides valuable insights into the cellular and molecular mechanisms underlying the hair growth-promoting effects of rhamnose. These findings highlight the potential for the therapeutic application of rhamnose in the treatment of alopecia.

pharmacology and toxicology↗

ARTEMIS integrates autoencoders and schrodinger bridges to predict continuous dynamics of gene expression, cell population and perturbation from time-series single-cell data

Cellular processes like development, differentiation, and disease progression are highly complex and dynamic (e.g., gene expression). These processes often un-dergo cell population changes driven by cell birth, proliferation, and death. Single-cell sequencing enables gene expression measurement at the cellular resolution, allowing us to decipher cellular and molecular dynamics underlying these pro-cesses. However, the high costs and destructive nature of sequencing restrict observations to snapshots of unaligned cells at discrete timepoints, limiting our understanding of these processes and complicating the reconstruction of cellular trajectories. To address this challenge, we propose ARTEMIS, a generative model integrating a variational autoencoder (VAE) with unbalanced Diffusion Schrodinger Bridge (uDSB) to model cellular processes by reconstructing cellular trajectories, reveal gene expression dynamics, and recover cell population changes. The VAE maps input time-series single-cell data to a continuous latent space, where trajectories are reconstructed by solving the Schrodinger bridge problem using forward-backward stochastic differential equations (SDEs). A drift function in the SDEs captures deterministic gene expression trends. An additional neural network estimates time-varying kill rates for single cells along trajectories, enabling recovery of cell population changes. Using three scRNA-seq datasets--pancreatic {beta}-cell differentiation, zebrafish embryogenesis, and epithelial-mesenchymal transition (EMT) in cancer cells--we demonstrate that ARTEMIS: (i) outperforms state-of-art methods to predict held-out timepoints, (ii) recovers relative cell population changes over time, and (iii) identifies "drift" genes driving deterministic expression trends in cell trajectories. Furthermore, in silico perturbations show that these genes influence processes like EMT. The code for ARTEMIS: https://github.com/daifengwanglab/ARTEMIS.

bioinformatics↗

Evolution of chronic lymphocytic leukemia after allogeneic stem cell transplant

Allogeneic stem cell transplant (alloSCT) for patients with relapsed/refractory chronic lymphocytic leukemia (CLL) can result in cure in some patients. Analogous to chemotherapy and targeted therapy, we hypothesized that allogeneic cellular immunotherapies, including alloSCT and donor lymphocyte infusion (DLI), would impact malignant evolution through the application of selective immunologic pressure with reciprocal changes in the T cell compartment. We tested a cohort of 24 patients treated with HLA-matched alloSCT +/- DLI, two mediators of the graft versus leukemia (GVL) effect. Comparison of pre-alloSCT samples revealed that a key difference between responders (n=13) and non-responders (n=11) is the cellularity of leukemic cells. We further mapped mutational trajectories of tumor cells by whole exome sequencing (WES) of sort-purified CLL in 11 post-transplant relapsed patients and found evidence of subclonal leukemic evolution in 8/11 patients after nonmyeloablative human leukocyte antigen (HLA)-matched alloSCT. Different patterns of CLL evolution were observed, and these changes included putative CLL drivers in every case. To investigate the presence of immune-related variants in patients, we collected 19 T cell co-culture CRISPR datasets and identified the top positive and negative regulators of cancer cells response to T-cell-dependent killing. We found that most mutations linked to T-cell killing emerged after allo-SCT treatment, suggesting that selective pressures from the GVL effect may drive the evolution of these mutations. Together, these data identify cellular homogeneity as a key biomarker for susceptibility to GVL-driven immunity in CLL and illustrate how the leukemic cells further evolve to evade immunosurveillance. SIGNIFICANCEThe impact of allogeneic stem cell transplant (alloSCT) on subclonal leukemia evolution remains poorly understood. By performing whole exome sequencing (WES) on pre- and post-alloSCT patient samples, we reveal different patterns of CLL evolution and potential immune-related driver genes influencing CLL relapse and refractory disease post-alloSCT.

cancer biology↗

Path of differentiation defines human macrophage identity

Macrophages play central roles in immunity, wound healing, and homeostasis - a functional diversity that is underpinned by varying developmental origins. The impact of ontogeny on properties of human macrophages is inadequately understood. We demonstrate that definitive human fetal liver (HFL) hematopoietic stem cells (HSCs) possess two divergent paths of macrophage specification that lead to distinct identities. The monocyte-dependent pathway exists in both prenatal and postnatal hematopoiesis and generates macrophages with adult-like responses properties. We now uncover a fetal-specific pathway of expedited differentiation that generates tissue resident-like macrophages (TRMs) that retain HSC-like self-renewal programs governed by the aryl hydrocarbon receptor (AHR). We show that AHR antagonism promotes TRM expansion and mitigates inflammation in models of atopic dermatitis (AD). Overall, we directly connect path of differentiation with functional properties of macrophages and identify an approach to promote selective expansion of TRMs with direct relevance to inflammation and diseases of macrophage dysfunction.

molecular biology↗

Dynamic activity of Erg promotes aging of the hematopoietic system

Hematopoiesis changes to adapt to the physiology of development and aging. Temporal changes in hematopoiesis parallel age-dependent incidences of blood diseases. Several heterochronic regulators of hematopoiesis have been identified, but how the master transcription factor (TF) circuitry of definitive hematopoietic stem cells (HSCs) adapts over the lifespan is unknown. Here, we show that expression of the ETS family TF Erg is adult-biased, and that programmed upregulation of Erg expression during juvenile to adult aging is evolutionarily conserved and required for complete implementation of adult patterns of HSC self-renewal and myeloid, erythroid, and lymphoid differentiation. Erg deficiency maintains fetal transcriptional and epigenetic programs, and persistent juvenile phenotypes in Erg haploinsufficient mice are dependent on deregulation of the fetal-biased TF Hmga2. Finally, Erg haploinsufficiency in the adult results in fetal-like resistance to leukemogenesis. Overall, we identify a mechanism whereby HSC TF networks are rewired to specify stage-specific hematopoiesis, a finding directly relevant to age-biased blood diseases. SUMMARYThe hematopoietic system undergoes a process of coordinated aging from the juvenile to adult states. Here, we find that expression of ETS family transcription factor Erg is temporally regulated. Impaired upregulation of Erg during the hematopoietic maturation results in persistence of juvenile phenotypes.

developmental biology↗

Decoding cellular transcriptional regulatory networks governing wheat inflorescence development

Wheat inflorescence architecture, particularly spikelet and floret development, is critical for grain yield. To decode the cellular transcriptional regulatory network (cTRN) underlying wheat inflorescence development, we integrated multiple single-cell omics technologies to construct a spatiotemporal atlas of transcriptional and chromatin accessibility dynamics. This comprehensive analysis identified 20 cell types, 7,211 cell type-specific genes and 152,333 cell type-specific accessible chromatin regions (csACRs) in the wheat inflorescence. Trajectory analysis identified two sub-clusters of proliferating cells as the origins of spikelet and floret formation, deviating from the traditional developmental model. Key transcription factors and hormone-related genes in the cTRN, along with the csACRs, providing new targets for modulating wheat inflorescence architecture. Our findings provide a high-resolution resource for crop inflorescence research and establish a paradigm for applying spatiotemporal single-cell omics analysis to plant biology.

plant biology↗

COSIME: Cooperative multi-view integration and Scalable and Interpretable Model Explainer

Single-omics approaches often provide a limited perspective on complex biological systems, whereas multi-omics integration enables a more comprehensive understanding by combining diverse data views. However, integrating heterogeneous data types and interpreting complex relationships between biological features--both within and across views--remains a major challenge. To address these challenges, we introduce COSIME (Cooperative Multi-view Integration with a Scalable and Interpretable Model Explainer). COSIME applies the backpropagation of a learnable optimal transport algorithm to deep neural networks, thus enabling the learning of latent features from several views to predict disease phenotypes. It also incorporates Monte Carlo sampling to enable interpretable assessments of both feature importance and pairwise feature interactions for both within and across views. We applied COSIME to both simulated and real-world datasets--including single-cell transcriptomics, spatial transcriptomics, epigenomics and metabolomics--to predict Alzheimers disease-related phenotypes. Benchmarking of existing methods demonstrated that COSIME improves prediction accuracy and provides interpretability. For example, it reveals that synergistic interactions between astrocyte and microglia genes associated with Alzheimers disease are more likely to localize at the edges of the middle temporal gyrus. Finally, COSIME is also publicly available as an open source tool.

bioinformatics↗

Extracellular stiffness regulates site-specific lung development

Extracellular matrix (ECM) stiffness plays a crucial role in regulating cell fate and maturation, but its influence on lung development is limited known. Here we utilized stiffness-tunable gelatin methacryloyl (GelMA) hydrogels to investigate how ECM stiffness influences site-specific lung development in a stem cell-derived lung organoid model. We found increased stiffness promoted NKX2-1+ lung progenitor cells (LPCs) generation. In airway organoids (hAWOs), stiff hydrogels directed proximal airway differentiation enriched with goblet, ciliated, and basal cells; whereas the decreased stiffness favored emergence of secretory cells in the proximal-distal transition zone and distal airway. In alveolar organoids (hALOs), increased stiffness enhanced AT2 and AT1 cells transition. Moreover, infection assays with Omicron BA.1.1 and Delta variants recapitulated the proximal-to-distal tropism of SARS-CoV-2 in the lung. Transcriptomic sequencing revealed ECM stiffness regulates lung development via Hippo, TGF-{beta}, HIF and Wnt pathways. These findings advance mechanism understanding of ECM stiffness on lung development and provide a novel mechanical regulation for generating site-specific lung organoids.

cell biology↗

Micromorphology and ammonium transmembrane transport characteristics in roots of rice seedlings

During the seedling stage, rice root exhibit rapid growth and absorb significant quantities of nutrients. This study involved cultivating rice seedlings in two different seedling-raising mediums characterized by high ammonium concentration (HN, NH4+ 1.2 mg g-1) and low ammonium concentration (LN, NH4+ 0.006 mg g-1). The morphology of distinct root zones (root cap, meristematic zone, elongation zone, and maturation zone) was observed under a microscope throughout root development, and variations in transmembrane flux rates of NH4+ in different root zones were assessed using Non-invasive micro-test technology (NMT). Results showed that the root caps of both seminal and adventitious roots became separated from the root tip between 9 and 12 days after root emergence. During this time, the root tip transformed from a sharp to a round shape, and the distance from the maturation zone to the root tip progressively decreased from over 900 m on 6 days after sowing (DAS) to under 500 m on DAS12. The meristematic zone was the primary site for NH4+ absorption in new root and proved to be particularly sensitive to environmental NH4+ concentration. At DAS 6, the net NH4+ flux rate was highest in the meristematic zone under both HN and LN treatments. Additionally, the external NH4+ concentration influenced the direction of NH4+ flux in the meristematic zone at DAS9, with HN being a net NH4+ influx and LN being an NH4+ efflux, and the net NH4+ influx in the meristematic zone persisted for 3 days longer in the HN treatment compared to the LN treatment. In mature roots, the root hair zone emerged as the primary site of NH4+ uptake, exhibiting an infNH4+ influx rate of 40-140 pmol cm-1 s-1, and this low rate of uptake could be sustained for up to 12 days after root emergence. By DAS15, a net NH4+ efflux was observed in the entire seminal root, signaling the loss of NH4+ absorption function 15 days post-emergence. A similar trend was noted in adventitious roots, where NH4+ uptake remained functional for 12-15 days after root emergence. As rice seedlings continued to grow, new adventitious roots replaced old ones, facilitating ongoing NH4+ uptake.

plant biology↗