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Jackson, D.

Publications and source records attributed to Jackson, D..

At least 19 recordsLinked to original sources

The cellular and genetic basis of inflorescence divergence between maize and teosinte

The domestication of maize from teosinte involved dramatic remodeling of the ear, yet the cellular and genetic bases of this transformation remain unclear. Here, we generate a single-nucleus and spatial transcriptome atlas of developing maize and teosinte ears. Comparative analysis reveals divergence in cob-associated cell types, with enhanced cytokinin signaling and reduced growth-inhibitory signals collectively driving cob thickening and enlargement in maize. We further demonstrate that domestication expanded the spatial expression domain of key transcription factors in maize meristem cells, enhancing the potential for increasing kernel number. Additionally, we verified a major domestication gene, ZmSPD1, in which two nonsynonymous SNPs differentiate maize from teosinte and alter jasmonic acid (JA) levels in the ear, thereby suppressing spikelet abortion to effectively double kernel production. These findings provide a cell-resolved mechanistic framework for how cob architecture and kernel number were shaped during maize domestication, offering new insights into the formation of key agronomic traits.

plant biology↗

Widespread introgression and a potential role for a neo-sex chromosome in booby diversification and speciation

Speciation in marine taxa is dynamic and complex, often occurring in the absence of absolute geographic barriers to gene flow. Boobies comprise a clade of seven highly mobile seabird species with high diversity in the eastern Pacific Ocean, where no land barriers separate extant sister species and hybridization is widespread. They exhibit striking diversity in bare-part coloration, an important signal of mate quality, and possess a novel multiple sex chromosome system (Z1Z2Z1Z2 / Z1Z2W), likely resulting from a fusion between an ancestral autosomal microchromosome and the W chromosome. To understand speciation processes in the context of gene flow, we sequenced and analyzed 29 short-read booby genomes and assembled a reference northern gannet genome to (1) test for introgression, (2) characterize genomic patterns of divergence across species, and (3) investigate the gene content and evolution of the neo-sex chromosome. We found that divergence among eastern Pacific sister taxa is temporally associated with periods of glacial maxima. Between periods of glacial maxima, two pairs of sister species (blue-footed and Peruvian boobies; masked and Nazca boobies) exhibit strong signatures of episodic introgression, indicating that speciation has occurred over multiple periods of divergence followed by gene flow. However, in the third pair of sister species, genomic signatures showed higher divergence within brown booby populations than between brown and Cocos boobies. We also identified the epidermal differentiation complex - a gene cassette involved in skin, feather, beak, and claw development - on the neo-sex region of the W chromosome, where it spans the boundary between the putatively recombining and non-recombining regions, with interspecific variation in the exact recombination suppression boundary. We inferred that this complex may contribute to diversity in feather and bare part coloration across boobies. Together, these results reveal that diversification and speciation in a clade of highly mobile seabirds emerged from a complex evolutionary history involving historical climate dynamics, introgression, and sex chromosome evolution.

evolutionary biology↗

Rethinking the movement ecology of Andean bears: temperature-driven cathemerality and seasonal space-use cycles

BackgroundThe Andean bear (Tremarctos ornatus), South Americas only ursid, is one of the worlds most elusive large mammals, making movement data collection exceptionally rare. Addressing this gap, we present the largest telemetry dataset ever assembled, spanning 19 individuals tracked across three Ecuadorian National Parks over two decades, paired with a novel analytical approach. MethodsWe integrated Continuous-Time Movement Models (CTMM), Auto-correlated Kernel Density Estimates (AKDEs), Hidden Markov Models (HMM) and a diel niche theoretical framework to mitigate biases previously unaccounted for the species in telemetry studies. Fine-scale AKDEs and non-linear movement metrics were calculated to understand seasonal space use and movement behaviors. Speed and diffusion from CTMM and behavioral states from HMM were modelled with environmental covariates to investigate which conditions shape diel and seasonal activity. ResultsPopulation mean home range was 138.2 km2 (95% Confidence Intervals 78.7-225.5), with males (239.8 km2, 182.8-307.5), significantly exceeding females (58.5 km2, 35.5-90.3). Notably, three females exhibited ranges comparable to some males. Weekly and monthly AKDEs uncovered cyclic home range dynamics potentially driven by resource availability, with contractions around corn harvests and berry seasons, and expansions during paramo transitions. Decoupling speed from diffusion rates showed region-specific behaviors: intensive patch exploitation in Llanganates, broad exploratory ranging in Cayambe-Coca, and suppressed female locomotion in Cotacachi-Cayapas. Statistical analyses identified temperature as a key diel modulator and precipitation as the seasonal driver. Foraging probability increased between 2:00-6:00, large displacements between 7:00-14:00, and nocturnal movement rose significantly under colder conditions. Across diel hypothesis frameworks, bears were classified as cathemeral rather than strictly diurnal, corroborated by camera-trap records from Colombia, Ecuador, and Peru. ConclusionsWe propose a cathemeral diel phenotype that responds to thermal fluctuations and situates Andean bears within a broader ursid context of thermoregulatory niche plasticity. This dataset reveals unprecedented resolution of regional and sex specific behaviors that will facilitate and accelerate comparative studies in rapidly changing Andean landscapes. By releasing this long-term dataset as an open resource, we provide a foundation for climate-resilient conservation strategies. More broadly, we advocate for data democratization and invite collaboration.

ecology↗

A deep-time landscape of plant cis-regulatory sequence evolution

Developmental gene function is often conserved over deep time, but cis-regulatory sequence conservation is difficult to identify. Rapid sequence turnover, paleopolyploidy, structural variation, and limited phylogenomic sampling have impeded conserved non-coding sequence (CNS) discovery. Using Conservatory, an algorithm that leverages microsynteny and iterative alignments to map CNS-gene associations over evolution, we uncovered [~]2.3 million CNSs, including over 3,000 predating angiosperms, from 284 plant species spanning 300 million years of diversification. Ancient CNSs were enriched near developmental regulators, and mutating CNSs near HOMEOBOX genes produced strong phenotypes. Tracing CNS evolution uncovered key principles: CNS spacing varies, but order is conserved; genomic rearrangements form new CNS-gene associations; and ancient CNSs are preferentially retained among paralogs, but are often lost as cohorts or evolve into lineage-specific CNSs. One Sentence SummaryConservatory maps ancient cis-regulatory elements and uncovers regulatory evolution dynamics.

plant biology↗

Non-catalytic and catalytic TREHALOSE-6-PHOSPHATE SYNTHASES interact with RAMOSA3 to control maize development.

Trehalose-6-phosphate (Tre6P) is the intermediate in the two-step pathway of trehalose biosynthesis mediated by Tre6P-synthases (TPSs) and Tre6P-phosphatases (TPPs). Plants harbor small families of TPS and TPP genes, however most plant TPSs lack enzymatic activity, suggesting they have regulatory functions. The classical mutant ramosa3 (ra3) increases inflorescence branching in maize, and RA3 encodes a catalytic TPP. We found that RA3 interacts with maize ZmTPS1, a non-catalytic TPS. Mutants in ZmTPS1 and its close paralog ZmTPS12 enhance ra3 phenotypes, suggesting their physical interaction is biologically significant. ZmTPS1 also interacts with the two catalytically active maize TPSs, ZmTPS11 and ZmTPS14, however zmtps11;zmtps14 double mutants fail to complete embryogenesis, suggesting that they are essential, as in arabidopsis. Interestingly, the non-catalytic ZmTPS1 protein stimulated the coupled activity of RA3 and ZmTPS14, suggesting that RA3, ZmTPS1, and ZmTPS14 form a complex, and we confirmed this by expressing and purifying the three proteins and by Alphafold predictions. Our results suggest that non-catalytic TPSs form a complex with catalytic TPSs and TPPs to stimulate catalytic activity and regulate plant development.

plant biology↗

Antagonistic interactions between CLAVATA receptors shape maize ear development

Meristem activity is controlled by the CLAVATA (CLV) signaling pathway, which involves a suite of leucine rich receptor (LRR) receptors, receptor-like proteins and CLV- EMBRYO SURROUNDING REGION (CLE) peptide ligands. FASCIATED EAR 3 (FEA3) is a leucine rich receptor (LRR) receptor-like protein important for meristem maintenance in maize, and acts independently of canonical CLV receptors. Weak alleles of fea3 can increase yield-related traits in maize, so understanding how FEA3 controls inflorescence development can maximize its potential as a crop improvement target. To identify FEA3s interaction network, we used TurboID-based proximity labeling in maize meristems, and identified a putative co-receptor, BARELY ANY MERISTEM 1D (BAM1D). BAM1D and FEA3 proximity labeling proteomes shared over 100 proteins, including many signaling proteins, suggesting they feed into a common signaling pathway. fea3 was epistatic to bam1d in the control of IM size, supporting the idea that FEA3 and BAM1D interact physically. However, fea3 and bam1d act antagonistically, because fea3 mutants had larger inflorescence meristems (IMs), whereas bam1d mutants produced smaller IMs. Together, this study demonstrates how in vivo TurboID-based proximity labeling clarifies complex genetic interactions between CLV receptors and expands our knowledge of downstream signaling components of CLV signaling pathways, which are largely uncharacterized. Our findings support the notion that multiple, partially overlapping CLV receptor complexes coordinately control meristem maintenance.

plant biology↗

Overcoming extensive redundancy in the arabidopsis TREHALOSE-6-PHOSPHATE PHOSPHATASE gene family reveals connections to development

Arabidopsis encodes ten TREHALOSE-6-PHOSPHATE PHOSPHATASE (TPP) genes, homologous to maize RAMOSA3 (I), which controls shoot branching. To explore the roles of the arabidopsis TPPs, we analyzed their expression in shoot apices and found distinct spatial patterns, including TPPI and TPPJ expressed in shoot meristem boundaries, reminiscent of RA3 expression. Single and double TPP mutants lacked dramatic phenotypes, however a CRISPR-Cas9 knockout of all ten TPP genes resulted in increased branching, mirroring ra3 mutants in maize, as well as reduced size and earlier flowering. Expression of GFP-tagged TPPI under its native promoter partially complemented these defects, with protein localization in meristems, vascular tissues and in nuclei. Metabolite profiling revealed higher trehalose 6-phosphate (Tre6P), lower trehalose, and altered sugar and iron-associated metabolites. The mutants also developed chlorosis and grew poorly on low-nutrient media, linked to low iron levels, and reversible with iron supplementation. Consistent with these findings, developmental and iron-responsive genes were up-regulated in the mutants, while photosynthesis-related genes were repressed. Our findings suggest that TPP genes redundantly regulate shoot architecture, sugar metabolism, iron homeostasis and photosynthesis in arabidopsis, and support a role for TPP-mediated Tre6P signaling in coordinating developmental and physiological pathways.

plant biology↗

Embryo-scale single-cell chemical transcriptomics reveals dependencies between cell types and signaling pathways

Organogenesis is a highly organized process that is conserved across vertebrates and is heavily dependent on intercellular signaling to achieve cell type identity. We lack a comprehensive understanding of how developing cell types in each organ and tissue depend on developmental signaling pathways. To address this gap in knowledge, we captured the molecular consequences of inhibiting each of the seven major developmental signaling pathways in zebrafish, using large-scale whole embryo single cell RNA-seq from over two million cells. This approach allowed us to detect signaling pathway regulation even in very rare cell types. By focusing on the development of the pectoral fin, we uncovered two new cell types (distal mesenchyme and tenocytes) and multiple novel signaling dependencies during pectoral fin development. This resource serves as a valuable tool for investigators seeking to rapidly assess the role of the major signaling pathways during the formation of their tissue of interest.

developmental biology↗

Volatile-suppressed peptide signaling enhances volatile responses in plant-plant interactions

Plant volatiles shape plant-plant interactions by acting as defense regulators and response factors. While plant volatile biosynthesis is well understood, how their emission is regulated remains largely elusive. Here, we show that small peptide signaling regulates induced volatile release in maize. Following herbivore attack, green leaf volatiles such as (Z)-3-hexenyl acetate (HAC) are released and induce terpene and indole emissions from neighboring plants. This process is accompanied by reduced expression of the ZmCLE1E9 gene and the ZmBAM1A, ZmBAM1B and ZmBAM3C receptor genes in HAC-exposed plants. Exogenous ZmCLE1E9 peptide inhibits HAC-triggered volatile release by limiting stomatal aperture. This inhibition disappears in the Zmbam1a/Zmbam1b/Zmbam3c triple mutant. Molecular docking supports ZmCLE1E9 and ZmBAMs as ligand-receptor pairs. Furthermore, Zmcle1e9 and Zmbams triple mutants show increased volatile emissions upon HAC exposure. In summary, we show that upon HAC perception, maize plants enhance their capacity to release terpenes and indole via the suppression of CLE1E9 signaling. This behavior allows maize plants to rapidly deploy volatile cues in response to stress volatiles and thus shape the infochemical dynamics of multitrophic environments.

plant biology↗

Cascading consequences of shifting ice phenology in an exploited lake

Ice phenology (onset and breakup of ice cover) regulates the timings of seasonal life history events of many animal and plant species in high-latitude lakes in the Northern Hemisphere, promoting the coexistence of species that share resources like food and shelter. Increasingly warmer, more variable Earths climate is, however, shifting ice phenology, modifying habitat conditions, and in turn reshaping the population and interaction dynamics of many species, threatening their persistence. Applying multivariate autoregressive state-space time series modeling to extensive historical and contemporary monitoring records (spanning 36 to 113 years) of limnological and biological surveys and fishery catches, we explore how shifting ice phenology propagates through a food web over time by modulating thermal profiles and limnological properties in Lake Simcoe, a large, intensely exploited system in southern Ontario, Canada. Analysis shows that increasingly earlier ice breakups, later ice freeze-ups, earlier thermal stratification onset, and later turnover since the early 1980s, attenuated algal production. This in turn, combined with increasingly more abundant invasive species (dreissenids) that promoted greater water clarity over prolonged stratification periods, diminished zooplankton abundances. These limnological changes filtered through plankton communities further modified the population and community dynamics of higher trophic-level species like fish with differential thermal preferences, interactively with time-varying non-climate drivers. Although management interventions-reductions in nutrient loading and fishing effort in particular-in recent decades aided the recoveries of depleted cold-adapted fish populations (including lake trout, lake whitefish, and cisco), their interaction patterns and strengths with species adapted to warmer conditions were reshuffled by advanced timings of ice breakup and delayed timings of ice freeze-up. These findings reveal how complex food web dynamics can emerge from ecologically divergent responses that reshape species interactions within and among trophic levels under shifting ice phenology filtered through bottom-up processes, likely buffering destabilizing effects of a changing climate.

ecology↗

Medicago truncatula CORYNE regulates inflorescence meristem branching, nutrient signaling, and arbuscular mycorrhizal symbiosis

The CLAVATA signaling pathway regulates plant development and plant-environment interactions. CLAVATA signaling consists of mobile, cell-type or environment-specific CLAVATA3/ESR-related (CLE) peptides, which are perceived by a receptor complex consisting of leucine-rich repeat receptor-like kinases such as CLAVATA1 and receptor-like proteins such as CLAVATA2, which often functions with the pseudokinase CORYNE (CRN). CLAVATA signaling has been extensively studied in various plant species for its role in meristem maintenance and in legumes for modulating root interactions with nitrogen-fixing rhizobia. Some signaling proteins involved in development and nodulation, including CLAVATA1, also regulate plant interactions with mutualistic arbuscular mycorrhizal (AM) fungi. However, our knowledge on AM symbiosis regulation by CLAVATA signaling remains limited and only a handful of genetic regulators have been identified. Here we report that Medicago truncatula CRN controls inflorescence meristem branching and negatively regulates root interactions with AM fungi. MtCRN functions partially independently of the AM autoregulation signal MtCLE53. Transcriptomic data revealed that crn roots display signs of perturbed nutrient, symbiosis, and stress signaling, suggesting that MtCRN plays various roles in plant development and interactions with the environment.

plant biology↗

Reticulate leaf venation in Pilea peperomioides is a Voronoi diagram

Reticulate leaf venation, characterized by the presence of loops, is a distinguishing feature of many flowering plants. However, our understanding of both the geometry and the morphogenesis of reticulate vein patterns is far from complete. We show that in the Chinese money plant (Pilea peperomioides), major veins form an approximate Voronoi diagram surrounding secretory pores known as hydathodes. We also propose a mechanistic model based on polar transport of the plant hormone auxin to produce Voronoi patterns. In contrast with classical models where veins directly connect auxin sources to sinks, our model generates veins that bisect the space between adjacent auxin sources, collectively forming loops. The paradigm change offered by this model may open the door to study reticulate vein formation in other species.

plant biology↗

Enhancing oncolytic virotherapy by exosome-mediated microRNA reprograming of the tumour microenvironment.

BackgroundThere has been limited success of cancer immunotherapies in the treatment of ovarian cancer (OvCa) to date, largely due to the immunosuppressive tumour microenvironment (TME). Tumour-associated macrophages (TAMs) are a major component of both the primary tumour and malignant ascites, promoting tumour growth, angiogenesis, metastasis, chemotherapy resistance and immunosuppression. Differential microRNA (miRNA) profiles have been implicated in the plasticity of TAMs. Therefore, delivering miRNA to TAMs to promote an anti-tumour phenotype is a novel approach to reverse their pro-tumour activity and enhance the efficacy of cancer immunotherapies. Oncolytic viruses (OVs) preferentially replicate in tumour cells making them ideal vehicles to deliver miRNA mimetics to the TME. Importantly, miRNA expressed by OVs get packaged within tumour-derived extracellular vesicles (TDEVs), and release of TDEV is augmented by OV infection, thus enhancing the dissemination of miRNA throughout the TME. MethodSmall RNAseq was used to identify differentially expressed miRNA during TAM generation and following LPS/IFN{gamma} stimulation to induce an anti-tumour phenotype. Two differentially expressed miRNA identified, miR-155 and miR-19a, were cloned into oncolytic rhabdovirus (ORV), and anti-tumour efficacy was investigated using both in vitro and in vivo models of OvCa. ResultsThis study demonstrates that ORV infection enhances TDEV production in OvCa cell lines both in vitro and in vivo and that TDEV are preferentially taken up by myeloid cells, including TAMs. Small RNAseq identified 23 miRNAs that were significantly upregulated in anti-tumour TAMs, including miR-155-5p. While 101 miRNAs were downregulated during pro-tumour TAM differentiation, including miR-19a-3p. Culturing TDEV expressing miR-155 or miR-19a with TAMs reversed their immunosuppressive activity, as measured by T cell proliferation. While ORV-miR-155 enhanced the generation of anti-tumour T cells, only ORV-miR19a significantly improved survival of mice bearing ovarian tumours. ConclusionThis study demonstrates (i) that arming ORVs with immunomodulatory miRNA is an effective approach to deliver miRNA to myeloid cells within the TME and (ii) that miRNA have the capacity to reverse the tumour promoting properties of TAMs and improve the efficacy of cancer immunotherapies, such as OV.

cancer biology↗

Large-scale single-cell profiling of stem cells uncovers redundant regulators of shoot development and yield trait variation

Stem cells in plant shoots are a rare population of cells that produce leaves, fruits and seeds, vital sources for food and bioethanol. Uncovering regulators expressed in these stem cells will inform crop engineering to boost productivity. Single-cell analysis is a powerful tool for identifying regulators expressed in specific groups of cells. However, accessing plant shoot stem cells is challenging. Recent single-cell analyses of plant shoots have not captured these cells, and failed to detect stem cell regulators like CLAVATA3 and WUSCHEL. In this study, we finely dissected stem cell-enriched shoot tissues from both maize and arabidopsis for single-cell RNA-seq profiling. We optimized protocols to efficiently recover thousands of CLAVATA3 and WUSCHEL expressed cells. A cross-species comparison identified conserved stem cell regulators between maize and arabidopsis. We also performed single-cell RNA-seq on maize stem cell overproliferation mutants to find additional candidate regulators. Expression of candidate stem cell genes was validated using spatial transcriptomics, and we functionally confirmed roles in shoot development. These candidates include a family of ribosome-associated RNA-binding proteins, and two families of sugar kinase genes related to hypoxia signaling and cytokinin hormone homeostasis. These large-scale single-cell profiling of stem cells provide a resource for mining stem cell regulators, which show significant association with yield traits. Overall, our discoveries advance the understanding of shoot development and open avenues for manipulating diverse crops to enhance food and energy security.

plant biology↗

MaizeCODE reveals bi-directionally expressed enhancers that harbor molecular signatures of maize domestication.

Modern maize was domesticated from Teosinte parviglumis, with subsequent introgressions from Teosinte mexicana, yielding increased kernel row number, loss of the hard fruit case and dissociation from the cob upon maturity, as well as fewer tillers. Molecular approaches have identified several transcription factors involved in the development of these traits, yet revealed that a complex regulatory network is at play. MaizeCODE deploys ENCODE strategies to catalog regulatory regions in the maize genome, generating histone modification and transcription factor ChIP-seq in parallel with transcriptomics datasets in 5 tissues of 3 inbred lines which span the phenotypic diversity of maize, as well as the teosinte inbred TIL11. Integrated analysis of these datasets resulted in the identification of a comprehensive set of regulatory regions in each inbred, and notably of distal enhancers which were differentiated from gene bodies by their lack of H3K4me1. Many of these distal enhancers expressed non- coding enhancer RNAs bi-directionally, reminiscent of "super enhancers" in animal genomes. We show that pollen grains are the most differentiated tissue at the transcriptomic level, and share features with endosperm that may be related to McClintocks chromosome breakage- fusion-bridge cycle. Conversely, ears have the least conservation between maize and teosinte, both in gene expression and within regulatory regions, reflecting conspicuous morphological differences selected during domestication. The identification of molecular signatures of domestication in transcriptional regulatory regions provides a framework for directed breeding strategies in maize.

plant biology↗

The maize PLASTID TERMINAL OXIDASE (PTOX) gene controls the carotenoid content of kernels.

O_LICarotenoids perform a broad range of important functions in humans; therefore, carotenoid biofortification of maize (Zea mays L.), one of the most highly produced cereal crops worldwide, would have a global impact on human health. C_LIO_LIPLASTID TERMINAL OXIDASE (PTOX) genes play an important role in carotenoid metabolism; however, the possible function of PTOX in carotenoid biosynthesis in maize has not yet been explored. In this study, we identified the maize PTOX gene ZmPTOX1 by forward genetic screening. C_LIO_LIWhile most higher plant species possess a single copy of the PTOX gene, maize carries two tandemly duplicated copies of ZmPTOX. Characterization of Zmptox1 mutants revealed that disrupting one copy of ZmPTOX1 was enough to impair carotenoid biosynthesis, indicating that ZmPTOX1 is essential for carotenoid biosynthesis in maize kernels. Remarkably, overexpression of ZmPTOX1 significantly improved the content of carotenoids, especially {beta}-carotene (provitamin A), which was increased by ~3-fold, in maize kernels. C_LIO_LIOverall, our study shows that ZmPTOX1 plays a crucial role in carotenoid biosynthesis in maize kernels and suggests that fine-tuning the expression of this gene could improve the nutritional value of cereal grains. C_LI

plant biology↗

IL-33-induced neutrophilic inflammation and NETosis underlie rhinovirus-triggered exacerbations of asthma

Rhinovirus-induced neutrophil extracellular traps (NETs) contribute to acute asthma exacerbations, however the molecular factors that trigger NETosis in this context remain ill-defined. Here, we sought to implicate a role for IL-33, an epithelial cell-derived alarmin rapidly released in response to infection. In mice with chronic experimental asthma (CEA), but not naive controls, rhinovirus inoculation induced an early (1 day post infection; dpi) inflammatory response dominated by neutrophils, neutrophil-associated cytokines (IL-1, IL-1{beta}, CXCL1) and NETosis, followed by a later, type-2 inflammatory phase (3-7 dpi), characterized by eosinophils, elevated IL-4 levels, and goblet cell hyperplasia. Notably, both phases were ablated by HpARI (Heligmosomoides polygyrus Alarmin Release Inhibitor), which blocks IL-33 release and signalling. Instillation of exogenous IL-33 recapitulated the rhinovirus-induced early phase, including the increased presence of NETs in the airway mucosa, in a PAD4-dependent manner. Ex vivo IL-33-stimulated neutrophils from mice with CEA, but not naive mice, underwent NETosis, and produced greater amounts of IL-1/{beta}, IL-4, and IL-5. In nasal samples from rhinovirus-infected people with asthma, but not healthy controls, IL-33 levels correlated with neutrophil elastase and dsDNA. Our findings suggest that IL-33 blockade ameliorates the severity of an asthma exacerbation by attenuating neutrophil recruitment and the downstream generation of NETs.

immunology↗

Computational Fontan Analysis: Preserving accuracy while expediting workflow

BackgroundPost-operative outcomes of the Fontan operation have been linked to graft shape after implantation. Computational fluid dynamics (CFD) simulations are used to explore different surgical options. The objective of this study is to perform a systematic in vitro validation for investigating the accuracy and efficiency of CFD simulation to predict Fontan hemodynamics. MethodsCFD simulations were performed to measure indexed power loss (iPL) and hepatic flow distribution (HFD) in 10 patient-specific Fontan models, with varying mesh and numerical solvers. The results were compared with a novel in vitro flow loop setup with 3D printed Fontan models. A high-resolution differential pressure sensor was used to measure the pressure drop for validating iPL predictions. Microparticles with particle filtering system were used to measure HFD. The computational time was measured for a representative Fontan model with different mesh sizes and numerical solvers. ResultsWhen compared to in vitro setup, variations in CFD mesh sizes had significant effect on HFD (p = 0.0002) but no significant impact on iPL (p = 0.069). Numerical solvers had no significant impact in both iPL (p = 0.50) and HFD (P = 0.55). A transient solver with 0.5 mm mesh size requires computational time 100 times more than a steady solver with 2.5 mm mesh size to generate similar results. ConclusionsThe predictive value of CFD for Fontan planning can be validated against an in vitro flow loop. The prediction accuracy can be affected by the mesh size, model shape complexity and flow competition.

bioinformatics↗