Nodulation Phenotype Research Articles

Reinforcement learning for individualized lung cancer screening schedules: A nested case–control study

AbstractBackgroundThe current guidelines for managing screen‐detected pulmonary nodules offer rule‐based recommendations for immediate diagnostic work‐up or follow‐up at intervals of 3, 6, or 12 months. Customized visit plans are lacking.PurposeTo develop individualized screening schedules using reinforcement learning (RL) and evaluate the effectiveness of RL‐based policy models.MethodsUsing a nested case–control design, we retrospectively identified 308 patients with cancer who had positive screening results in at least two screening rounds in the National Lung Screening Trial. We established a control group that included cancer‐free patients with nodules, matched (1:1) according to the year of cancer diagnosis. By generating 10,164 sequence decision episodes, we trained RL‐based policy models, incorporating nodule diameter alone, combined with nodule appearance (attenuation and margin) and/or patient information (age, sex, smoking status, pack‐years, and family history). We calculated rates of misdiagnosis, missed diagnosis, and delayed diagnosis, and compared the performance of RL‐based policy models with rule‐based follow‐up protocols (National Comprehensive Cancer Network guideline; China Guideline for the Screening and Early Detection of Lung Cancer).ResultsWe identified significant interactions between certain variables (e.g., nodule shape and patient smoking pack‐years, beyond those considered in guideline protocols) and the selection of follow‐up testing intervals, thereby impacting the quality of the decision sequence. In validation, one RL‐based policy model achieved rates of 12.3% for misdiagnosis, 9.7% for missed diagnosis, and 11.7% for delayed diagnosis. Compared with the two rule‐based protocols, the three best‐performing RL‐based policy models consistently demonstrated optimal performance for specific patient subgroups based on disease characteristics (benign or malignant), nodule phenotypes (size, shape, and attenuation), and individual attributes.ConclusionsThis study highlights the potential of using an RL‐based approach that is both clinically interpretable and performance‐robust to develop personalized lung cancer screening schedules. Our findings present opportunities for enhancing the current cancer screening system.

GmNLP1 and GmNLP4 activate nitrate-induced CLE peptides NIC1a/b to mediate nitrate-regulated root nodulation.

Symbiotic nitrogen fixation is an energy-intensive process, to maintain the balance between growth and nitrogen fixation, high concentrations of nitrate inhibit root nodulation. However, the precise mechanism underlying the nitrate inhibition of nodulation in soybean remains elusive. In this study, CRISPR-Cas9-mediated knockout of GmNLP1 and GmNLP4 unveiled a notable nitrate-tolerant nodulation phenotype. GmNLP1b and GmNLP4a play a significant role in the nitrate-triggered inhibition of nodulation, as the expression of nitrate-responsive genes was largely suppressed in Gmnlp1b and Gmnlp4a mutants. Furthermore, we demonstrated that GmNLP1b and GmNLP4a can bind to the promoters of GmNIC1a and GmNIC1b and activate their expression. Manipulations targeting GmNIC1a and GmNIC1b through knockdown or overexpression strategies resulted in either increased or decreased nodule number in response to nitrate. Additionally, transgenic roots that constitutively express GmNIC1a or GmNIC1b rely on both NARK and hydroxyproline O-arabinosyltransferase RDN1 to prevent the inhibitory effects imposed by nitrate on nodulation. In conclusion, this study highlights the crucial role of the GmNLP1/4-GmNIC1a/b module in mediating high nitrate-induced inhibition of nodulation.

Isolation and Identification of Salinity-Tolerant Rhizobia and Nodulation Phenotype Analysis in Different Soybean Germplasms.

Increasing the soybean-planting area and increasing the soybean yield per unit area are two effective solutions to improve the overall soybean yield. Northeast China has a large saline soil area, and if soybeans could be grown there with the help of isolated saline-tolerant rhizobia, the soybean cultivation area in China could be effectively expanded. In this study, soybeans were planted in soils at different latitudes in China, and four strains of rhizobia were isolated and identified from the soybean nodules. According to the latitudes of the soil-sampling sites from high to low, the four isolated strains were identified as HLNEAU1, HLNEAU2, HLNEAU3, and HLNEAU4. In this study, the isolated strains were identified for their resistances, and their acid and saline tolerances and nitrogen fixation capacities were preliminarily identified. Ten representative soybean germplasm resources in Northeast China were inoculated with these four strains, and the compatibilities of these four rhizobium strains with the soybean germplasm resources were analyzed. All four isolates were able to establish different extents of compatibility with 10 soybean resources. Hefeng 50 had good compatibility with the four isolated strains, while Suinong 14 showed the best compatibility with HLNEAU2. The isolated rhizobacteria could successfully establish symbiosis with the soybeans, but host specificity was also present. This study was a preliminary exploration of the use of salinity-tolerant rhizobacteria to help the soybean nitrogen fixation in saline soils in order to increase the soybean acreage, and it provides a valuable theoretical basis for the application of saline-tolerant rhizobia.

Single-cell RNA sequencing reveals transdifferentiation of parathyroid chief cells into oxyphil cells in patients with uremic secondary hyperparathyroidism

The parathyroid gland is one of the main organs that regulate calcium and phosphorus metabolism. It is mainly composed of chief cells and oxyphil cells. Oxyphil cell counts are low in the parathyroid glands of healthy adults but are dramatically increased in patients with uremia and secondary hyperparathyroidism (SHPT). Increased oxyphil cell counts are related to drug treatment resistance, but the origin of oxyphil cells and the mechanism of proliferation remain unknown. Herein, three types of parathyroid nodules (chief cell nodules, oxyphil cell nodules and mixed nodules, respectively) excised from parathyroid glands of uremic SHPT patients were used for single-cell RNA sequencing (scRNA-seq), other molecular biology studies, and transplantation into nude mice. Through scRNA-seq of parathyroid mixed nodules from three patients with uremic SHPT, we established the first transcriptomic map of the human parathyroid and found a chief-to-oxyphil cell transdifferentiation characterized by gradual mitochondrial enrichment associated with the uremic milieu. Notably, the mitochondrial enrichment and cellular proliferation of chief cell and oxyphil cell nodules decreased significantly after leaving the uremic milieu via transplantation into nude mice. Remarkably, the phenotype of oxyphil cell nodules improved significantly in the nude mice as characterized by decreased mitochondrial content and the proportion of oxyphil cells to chief cells. Thus, our study provides a comprehensive single-cell transcriptome atlas of the human parathyroid and elucidates the origin of parathyroid oxyphil cells and their underlying transdifferentiating mechanism. These findings enhance our understanding of parathyroid disease and may open new treatment perspectives for patients with chronic kidney disease.

Molecular module GmPTF1a/b-GmNPLa regulates rhizobia infection and nodule formation in soybean.

Nodulation begins with the initiation of infection threads (ITs) in root hairs. Though mutual recognition and early symbiotic signaling cascades in legumes are well understood, molecular mechanisms underlying bacterial infection processes and successive nodule organogenesis remain largely unexplored. We functionally investigated a novel pectate lyase enzyme, GmNPLa, and its transcriptional regulator GmPTF1a/b in soybean (Glycine max), where their regulatory roles in IT development and nodule formation were elucidated through investigation of gene expression patterns, bioinformatics analysis, biochemical verification of genetic interactions, and observation of phenotypic impacts in transgenic soybean plants. GmNPLa was specifically induced by rhizobium inoculation in root hairs. Manipulation of GmNPLa produced remarkable effects on IT and nodule formation. GmPTF1a/b displayed similar expression patterns as GmNPLa, and manipulation of GmPTF1a/b also severely influenced nodulation traits. LI soybeans with low nodulation phenotypes were nearly restored to HI nodulation level by complementation of GmNPLa and/or GmPTF1a. Further genetic and biochemical analysis demonstrated that GmPTF1a can bind to the E-box motif to activate transcription of GmNPLa, and thereby facilitate nodulation. Taken together, our findings potentially reveal novel mediation of cell wall gene expression involving the basic helix-loop-helix transcription factor GmPTF1a/b acts as a key early regulator of nodulation in soybean.

Targeted mutagenesis of Medicago truncatula Nodule-specific Cysteine-Rich (NCR) genes using the Agrobacterium rhizogenes-mediated CRISPR/Cas9 system

The host-produced nodule specific cysteine-rich (NCR) peptides control the terminal differentiation of endosymbiotic rhizobia in the nodules of IRLC legumes. Although the Medicago truncatula genome encodes about 700 NCR peptides, only few of them have been proven to be crucial for nitrogen-fixing symbiosis. In this study, we applied the CRISPR/Cas9 gene editing technology to generate knockout mutants of NCR genes for which no genetic or functional data were previously available. We have developed a workflow to analyse the mutation and the symbiotic phenotype of individual nodules formed on Agrobacterium rhizogenes-mediated transgenic hairy roots. The selected NCR genes were successfully edited by the CRISPR/Cas9 system and nodules formed on knockout hairy roots showed wild type phenotype indicating that peptides NCR068, NCR089, NCR128 and NCR161 are not essential for symbiosis between M. truncatula Jemalong and Sinorhizobium medicae WSM419. We regenerated stable mutants edited for the NCR068 from hairy roots obtained by A. rhizogenes-mediated transformation. The analysis of the symbiotic phenotype of stable ncr068 mutants showed that peptide NCR068 is not required for symbiosis with S. meliloti strains 2011 and FSM-MA either. Our study reports that gene editing can help to elicit the role of certain NCRs in symbiotic nitrogen fixation.

Proteomic and Mutant Analysis of Hydrogenase Maturation Protein Gene hypE in Symbiotic Nitrogen Fixation of Mesorhizobium huakuii.

Hydrogenases catalyze the simple yet important redox reaction between protons and electrons and H2, thus mediating symbiotic interactions. The contribution of hydrogenase to this symbiosis and anti-oxidative damage was investigated using the M. huakuii hypE (encoding hydrogenase maturation protein) mutant. The hypE mutant grew a little faster than its parental 7653R and displayed decreased antioxidative capacity under H2O2-induced oxidative damage. Real-time quantitative PCR showed that hypE gene expression is significantly up-regulated in all the detected stages of nodule development. Although the hypE mutant can form nodules, the symbiotic ability was severely impaired, which led to an abnormal nodulation phenotype coupled to a 47% reduction in nitrogen fixation capacity. This phenotype was linked to the formation of smaller abnormal nodules containing disintegrating and prematurely senescent bacteroids. Proteomics analysis allowed a total of ninety differentially expressed proteins (fold change > 1.5 or <0.67, p < 0.05) to be identified. Of these proteins, 21 are related to stress response and virulence, 21 are involved in transporter activity, and 18 are involved in energy and nitrogen metabolism. Overall, the HypE protein is essential for symbiotic nitrogen fixation, playing independent roles in supplying energy and electrons, in bacterial detoxification, and in the control of bacteroid differentiation and senescence.

QTL Mapping and Functional Identification of Candidate Genes Regulated by Sinorhizobium fredii HH103 and Associated with Nodulation Traits in Soybean

Large amounts of nitrogen fertilizer are annually applied to improve soybean yield. However, the overuse of nitrogen fertilizers has resulted in significant environmental pollution. Biological nitrogen fixation is an ecological and environmentally friendly method to increase soybean yield. However, the signaling pathway and function of genes in the plant host regulated by rhizobia under the symbiotic relationship remain unknown. In this study, the chromosome region in soybean responsive to Sinorhizobium fredii HH103 was identified using chromosome-segment-substituted lines produced from a cross between cultivated soybean SN14 and wild soybean Zyd00006. In addition, candidate genes associated with nodulation traits and regulated by S. fredii HH103 were identified. In total, three quantitative trait loci (QTLs) containing 68 genes were identified on chromosomes 02, 05, and 20. The differentially expressed genes among the QTL regions were determined using RNA-seq and qRT-PCR. Glyma. 05G240500, a potential gene responding to S. fredii HH103 and positively regulating soybean nodulation, was identified. To explore the relationships between haplotypes and soybean nodulation phenotypes, SNPs found in the regulatory areas of Glyma.05G240500 haplotype were investigated. Our study revealed the role of Glyma.05G240500 in symbiosis and provided a reference for facilitating symbiotic nitrogen fixation in the field and for marker-assisted selection.

CRK12: A Key Player in Regulating the Phaseolus vulgaris-Rhizobium tropici Symbiotic Interaction.

Cysteine-rich receptor-like kinases (CRKs) are a type of receptor-like kinases (RLKs) that are important for pathogen resistance, extracellular reactive oxygen species (ROS) signaling, and programmed cell death in plants. In a previous study, we identified 46 CRK family members in the Phaseolus vulgaris genome and found that CRK12 was highly upregulated under root nodule symbiotic conditions. To better understand the role of CRK12 in the Phaseolus-Rhizobia symbiotic interaction, we functionally characterized this gene by overexpressing (CRK12-OE) and silencing (CRK12-RNAi) it in a P. vulgaris hairy root system. We found that the constitutive expression of CRK12 led to an increase in root hair length and the expression of root hair regulatory genes, while silencing the gene had the opposite effect. During symbiosis, CRK12-RNAi resulted in a significant reduction in nodule numbers, while CRK12-OE roots showed a dramatic increase in rhizobial infection threads and the number of nodules. Nodule cross sections revealed that silenced nodules had very few infected cells, while CRK12-OE nodules had enlarged infected cells, whose numbers had increased compared to controls. As expected, CRK12-RNAi negatively affected nitrogen fixation, while CRK12-OE nodules fixed 1.5 times more nitrogen than controls. Expression levels of genes involved in symbiosis and ROS signaling, as well as nitrogen export genes, supported the nodule phenotypes. Moreover, nodule senescence was prolonged in CRK12-overexpressing roots. Subcellular localization assays showed that the PvCRK12 protein localized to the plasma membrane, and the spatiotemporal expression patterns of the CRK12-promoter::GUS-GFP analysis revealed a symbiosis-specific expression of CRK12 during the early stages of rhizobial infection and in the development of nodules. Our findings suggest that CRK12, a membrane RLK, is a novel regulator of Phaseolus vulgaris-Rhizobium tropici symbiosis.

The Medicago truncatula nodule-specific cysteine-rich peptides, NCR343 and NCR-new35 are required for the maintenance of rhizobia in nitrogen-fixing nodules.

In the nodules of IRLC legumes, including Medicago truncatula, nitrogen-fixing rhizobia undergo terminal differentiation resulting in elongated and endoreduplicated bacteroids specialized for nitrogen fixation. This irreversible transition of rhizobia is mediated by host produced nodule-specific cysteine-rich (NCR) peptides, of which c. 700 are encoded in the M.truncatula genome but only few of them have been proved to be essential for nitrogen fixation. We carried out the characterization of the nodulation phenotype of three ineffective nitrogen-fixing M. truncatula mutants using confocal and electron microscopy, monitored the expression of defence and senescence-related marker genes, and analysed the bacteroid differentiation with flow cytometry. Genetic mapping combined with microarray- or transcriptome-based cloning was used to identify the impaired genes. Mtsym19 and Mtsym20 mutants are defective in the same peptide NCR-new35 and the lack of NCR343 is responsible for the ineffective symbiosis of NF-FN9363. We found that theexpression of NCR-new35 is significantly lower and limited to the transition zone of the nodule compared with other crucial NCRs. The fluorescent protein-tagged version of NCR343 and NCR-new35 localized to the symbiotic compartment. Our discovery added two additional members to the group of NCR genes essential for nitrogen-fixing symbiosis in M. truncatula.

MsSPL9 Modulates Nodulation under Nitrate Sufficiency Condition in Medicago sativa.

Nodulation in Leguminous spp. is induced by common environmental cues, such as low nitrogen availability conditions, in the presence of the specific Rhizobium spp. in the rhizosphere. Medicago sativa (alfalfa) is an important nitrogen-fixing forage crop that is widely cultivated around the world and relied upon as a staple source of forage in livestock feed. Although alfalfa's relationship with these bacteria is one of the most efficient between rhizobia and legume plants, breeding for nitrogen-related traits in this crop has received little attention. In this report, we investigate the role of Squamosa-Promoter Binding Protein-Like 9 (SPL9), a target of miR156, in nodulation in alfalfa. Transgenic alfalfa plants with SPL9-silenced (SPL9-RNAi) and overexpressed (35S::SPL9) were compared to wild-type (WT) alfalfa for phenotypic changes in nodulation in the presence and absence of nitrogen. Phenotypic analyses showed that silencing of MsSPL9 in alfalfa caused an increase in the number of nodules. Moreover, the characterization of phenotypic and molecular parameters revealed that MsSPL9 regulates nodulation under a high concentration of nitrate (10 mM KNO3) by regulating the transcription levels of the nitrate-responsive genes Nitrate Reductase1 (NR1), NR2, Nitrate transporter 2.5 (NRT2.5), and a shoot-controlled autoregulation of nodulation (AON) gene, Super numeric nodules (SUNN). While MsSPL9-overexpressing transgenic plants have dramatically increased transcript levels of SUNN, NR1, NR2, and NRT2.5, reducing MsSPL9 caused downregulation of these genes and displayed a nitrogen-starved phenotype, as downregulation of the MsSPL9 transcript levels caused a nitrate-tolerant nodulation phenotype. Taken together, our results suggest that MsSPL9 regulates nodulation in alfalfa in response to nitrate.

A high-resolution transcriptomic atlas depicting nitrogen fixation and nodule development in soybean.

Although root nodules are essential for biological nitrogen fixation in legumes, the cell types and molecular regulatory mechanisms contributing to nodule development and nitrogen fixation in determinate nodule legumes, such as soybean (Glycine max), remain incompletely understood. Here, we generated a single-nucleus resolution transcriptomic atlas of soybean roots and nodules at 14 days post inoculation (dpi) and annotated 17 major cell types, including six that are specific to nodules. We identified the specific cell types responsible for each step in the ureides synthesis pathway, which enables spatial compartmentalization of biochemical reactions during soybean nitrogen fixation. By utilizing RNA velocity analysis, we reconstructed the differentiation dynamics of soybean nodules, which differs from those of indeterminate nodules in Medicago truncatula. Moreover, we identified several putative regulators of soybean nodulation and two of these genes, GmbHLH93 and GmSCL1, were as-yet uncharacterized in soybean. Overexpression of each gene in soybean hairy root systems validated their respective roles in nodulation. Notably, enrichment for cytokinin-related genes in soybean nodules led to identification of the cytokinin receptor, GmCRE1, as a prominent component of the nodulation pathway. GmCRE1 knockout in soybean resulted in a striking nodule phenotype with decreased nitrogen fixation zone and depletion of leghemoglobins, accompanied by downregulation of nodule-specific gene expression, as well as almost complete abrogation of biological nitrogen fixation. In summary, this study provides a comprehensive perspective of the cellular landscape during soybean nodulation, shedding light on the underlying metabolic and developmental mechanisms of soybean nodule formation.

NODULE INCEPTION: a direct regulator of gibberellin biosynthesis during symbiotic nodulation.

This article is a Commentary on Gao et al. (2023), 239: 459–465.

GmTCP and GmNLP Underlying Nodulation Character in Soybean Depending on Nitrogen.

Soybean is a cereal crop with high protein and oil content which serves as the main source of plant-based protein and oil for human consumption. The symbiotic relationship between legumes and rhizobia contributes significantly to soybean yield and quality, but the underlying molecular mechanisms remain poorly understood, hindering efforts to improve soybean productivity. In this study, we conducted a transcriptome analysis and identified 22 differentially expressed genes (DEGs) from nodule-related quantitative trait loci (QTL) located in chromosomes 12 and 19. Subsequently, we performed functional characterisation and haplotype analysis to identify key candidate genes among the 22 DEGs that are responsive to nitrate. Our findings identified GmTCP (TEOSINTE-BRANCHED1/CYCLOIDEA/PCF) and GmNLP (NIN-LIKE PROTEIN) as the key candidate genes that regulate the soybean nodule phenotype in response to nitrogen concentration. We conducted homologous gene mutant analysis in Arabidopsis thaliana, which revealed that the homologous genes of GmTCP and GmNLP play a vital role in regulating root development in response to nitrogen concentration. We further performed overexpression and gene knockout of GmTCP and GmNLP through hairy root transformation in soybeans and analysed the effects of GmTCP and GmNLP on nodulation under different nitrogen concentrations using transgenic lines. Overexpressing GmTCP and GmNLP resulted in significant differences in soybean hairy root nodulation phenotypes, such as nodule number (NN) and nodule dry weight (NDW), under varying nitrate conditions. Our results demonstrate that GmTCP and GmNLP are involved in regulating soybean nodulation in response to nitrogen concentration, providing new insights into the mechanism of soybean symbiosis establishment underlying different nitrogen concentrations.

A Novel Rhizobium sp. Chiba-1 Strain Exhibits a Host Range for Nodule Symbiosis in Lotus Species.

Rhizobia are soil bacteria that induce the formation of nodules in the roots of leguminous plants for mutualistic establishment. Although the symbiotic mechanism between Lotus japonicus and its major symbiotic rhizobia, Mesorhizobium loti, has been extensively characterized, our understanding of symbiotic mechanisms, such as host specificity and host ranges, remains limited. In the present study, we isolated a novel Rhizobium strain capable of forming nodules on L. burttii from agricultural soil at Iwate prefecture in Japan. We conducted genomic and host range ana-lyses of various Lotus species. The results obtained revealed that the novel isolated Rhizobium sp. Chiba-1 was closely related to R. leguminosarum and had a wide host range that induced nodule development, including L. burttii and several L. japonicus wild-type accessions. However, L. japonicus Gifu exhibited an incompatible nodule phenotype. We also identified the formation of an epidermal infection threads that was dependent on the Lotus species and independent of nodule organ development. In conclusion, this newly isolated Rhizobium strain displays a distinct nodulation phenotype from Lotus species, and the results obtained herein provide novel insights into the functional mechanisms underlying host specificity and host ranges.

Symbiotic Nodule Development and Efficiency in the Medicago truncatula Mtefd-1 Mutant Is Highly Dependent on Sinorhizobium Strains.

Symbiotic nitrogen fixation (SNF) can play a key role in agroecosystems to reduce the negative impact of nitrogen fertilizers. Its efficiency is strongly affected by the combination of bacterial and plant genotypes, but the mechanisms responsible for the differences in the efficiency of rhizobium strains are not well documented. In Medicago truncatula, SNF has been mostly studied using model systems, such as M. truncatula A17 in interaction with Sinorhizobium meliloti Sm2011. Here we analyzed both the wild-type (wt) A17 and the Mtefd-1 mutant in interaction with five S. meliloti and two Sinorhizobium medicae strains. ETHYLENE RESPONSE FACTOR REQUIRED FOR NODULE DIFFERENTIATION (MtEFD) encodes a transcription factor, which contributes to the control of nodule number and differentiation in M. truncatula. We found that, in contrast to Sm2011, four strains induce functional (Fix+) nodules in Mtefd-1, although less efficient for SNF than in wt A17. In contrast, the Mtefd-1 hypernodulation phenotype is not strain-dependent. We compared the plant nodule transcriptomes in response to SmBL225C, a highly efficient strain with A17, versus Sm2011, in wt and Mtefd-1 backgrounds. This revealed faster nodule development with SmBL225C and early nodule senescence with Sm2011. These RNA sequencing analyses allowed us to identify candidate plant factors that could drive the differential nodule phenotype. In conclusion, this work shows the value of having a set of rhizobium strains to fully evaluate the biological importance of a plant symbiotic gene.

MRI Features Associated with Histology of Benign Prostatic Hyperplasia Nodules: Generation of a Predictive Model.

Background: Histologic phenotypic variation of benign prostatic hyperplasia (BPH) has been hypothesized to underlie response to medical therapy. We evaluate preoperative MRI of robot-assisted simple prostatectomy (RASP) specimens and determine imaging features associated with histologic phenotype. Materials and Methods: All patients undergoing RASP from November 2015 to November 2019 with a multiparametric MRI ≤1 year before RASP were included. Patients without identifiable BPH nodules on histologic specimens were excluded. Histology slides were obtained from whole mount adenoma specimens and corresponding MRI were reviewed and graded independently by a blinded expert in BPH histopathology (D.W.S.) and an experienced radiologist specializing in prostate imaging (D.N.C.), respectively. Each nodule was assigned a phenotypic score on a 5-point Likert scale (1 = predominantly glandular; 5 = predominantly stromal) by each reviewer. Scores were compared using the sign test and univariate analysis. Signal intensity relative to background transition zone and nodule texture were noted on T2, diffusion-weighted imaging (DWI), and dynamic contrast-enhanced (DCE) imaging sequences. Univariate and multivariate stepwise linear regression analysis were conducted to identify MRI features associated with histology score. All analyses were performed using Statistical Analysis System (version 9.4). Results: A total of 99 prostate nodules in 29 patients were included. Median phenotypic scores by histology and MRI were comparable (2, interquartile range [IQR] 2-3 vs 2, IQR 2-4, respectively; p = 0.63). Histology scores were positively correlated with MRI scores (Pearson's correlation 0.84, p < 0.0001). Multivariate stepwise linear regression analysis showed that low apparent diffusion coefficient (ADC) signal intensity (p < 0.001) and DCE wash-in (p = 0.03) were positively associated with more stromal histology, whereas ADC standard deviation (p = 0.03), DCE wash-out (p = 0.001), and heterogeneous T2 texture (p = 0.003) were associated with more glandular histology. Conclusion: There is a strong correlation between MRI features and the histologic phenotype of BPH nodules. MRI may provide a noninvasive method to determine underlying BPH nodule histology.

Spatiotemporal changes in gibberellin content are required for soybean nodulation.

The plant hormone gibberellin (GA) is required at different stages of legume nodule development, with its spatiotemporal distribution tightly regulated. Transcriptomic and bioinformatic analyses established that several key GA biosynthesis and catabolism enzyme encoding genes are critical to soybean (Glycine max) nodule formation. We examined the expression of several GA oxidase genes and used a Förster resonance energy transfer-based GA biosensor to determine the bioactive GA content of roots inoculated with DsRed-labelled Bradyrhizobium diazoefficiens. We manipulated the level of GA by genetically disrupting the expression of GA oxidase genes. Moreover, exogenous treatment of soybean roots with GA3 induced the expression of key nodulation genes and altered infection thread and nodule phenotypes. GmGA20ox1a, GmGA3ox1a, and GmGA2ox1a are upregulated in soybean roots inoculated with compatible B. diazoefficiens. GmGA20ox1a expression is predominately localized to the transient meristem of soybean nodules and coincides with the spatiotemporal distribution of bioactive GA occurring throughout nodule organogenesis. GmGA2ox1a exhibits a nodule vasculature-specific expression pattern, whereas GmGA3ox1a can be detected throughout the nodule and root. Disruptions in the level of GA resulted in aberrant rhizobia infection and reduced nodule numbers. Collectively, our results establish a central role for GAs in root hair infection by symbiotic rhizobia and in nodule organogenesis.

Symbiosis Contribution of Non-nodulating Bradyrhizobium cosmicum S23321 after Transferal of the Symbiotic Plasmid pDOA9.

The symbiotic properties of rhizobial bacteria are driven by the horizontal gene transfer of symbiotic genes, which are located in symbiosis islands or on plasmids. The symbiotic megaplasmid pDOA9 of Bradyrhizobium sp. DOA9, carrying the nod, nif, fix, and type three secretion system (T3SS) genes, has been conjugatively transferred to different Bradyrhizobium strains. In the present study, non-nodulating B. cosmicum S23321, which shows a close phylogenetic relationship with Bradyrhizobium sp. DOA9, but lacks symbiotic properties, was used to carry pDOA9 (annotated as chimeric S2:pDOA9). The results obtained showed that pDOA9 conferred symbiotic properties on S23321; however, nodulation phenotypes varied among the DOA9, chimeric ORS278:pDOA9, and S2:pDOA9 strains even though they all carried symbiotic pDOA9 plasmid. S23321 appeared to gain symbiotic nodulation from pDOA9 by processing nodulation genes and broadening the host range. The present results also showed the successful formation of active nodules in Arachis hypogaea (Dalbergoid) and Vigna radiata (Millitoid) by chimeric S2:pDOA9, while Crotalaria juncea (Genistoid) and Macroptilium atropurpureum (Millitoid) formed nodule-like structures. The formation of nodules and nodule-like structures occurred in a nod factor-dependent manner because the nod factor-lacking strain (S2:pDOA9ΩnodB) completely abolished nodulation in all legumes tested. Moreover, T3SS carried by S2:pDOA9 exerted negative effects on symbiosis with Crotalaria juncea, which was consistent with the results obtained on DOA9. T3SS exhibited symbiotic compatibility with V. radiata when nodulated by S23321. These outcomes implied that pDOA9 underwent changes during legume evolution that broadened host specificity and the compatibility of nodulation in a manner that was dependent on the chromosomal background of the recipient as well as legume host restrictions.

MP22-12 MAGNETIC RESONANCE IMAGING FEATURES ASSOCIATED WITH HISTOLOGY OF BENIGN PROSTATIC HYPERPLASIA NODULES: A PREDICTIVE MODEL

You have accessJournal of UrologyImaging/Radiology: Uroradiology II (MP22)1 Sep 2021MP22-12 MAGNETIC RESONANCE IMAGING FEATURES ASSOCIATED WITH HISTOLOGY OF BENIGN PROSTATIC HYPERPLASIA NODULES: A PREDICTIVE MODEL Jessica Dai, Tara Morgan, Ramy Goueli, Daniel Parrott, Douglas Strand, Daniel Costa, Claus Roehrborn, and Jeffrey Gahan Jessica DaiJessica Dai More articles by this author , Tara MorganTara Morgan More articles by this author , Ramy GoueliRamy Goueli More articles by this author , Daniel ParrottDaniel Parrott More articles by this author , Douglas StrandDouglas Strand More articles by this author , Daniel CostaDaniel Costa More articles by this author , Claus RoehrbornClaus Roehrborn More articles by this author , and Jeffrey GahanJeffrey Gahan More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002013.12AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Histologic phenotypic variation of benign prostatic hyperplasia (BPH) has been previously described and is hypothesized to underlie response to medical therapy. In this study, we evaluate pre-operative magnetic resonance imaging (MRI) of robotic simple prostatectomy (RASP) specimens and determine imaging features associated with histologic phenotype. METHODS: All patients undergoing RASP from 11/2015 to 11/2019 with multiparametric MRI ≤1 year before surgery were included. Those with no obvious BPH nodules on histologic specimens were excluded. Histology slides and corresponding MRI were reviewed independently by a blinded cell biology Ph.D. and radiologist, respectively. Each nodule was assigned a phenotypic score on a 5-point Likert scale (1=predominantly glandular, 5=predominantly stromal). Scores were compared using the sign test and univariate analysis. Signal intensity relative to transition zone and nodule texture were noted on T2, diffusion-weighted imaging (DWI), and dynamic contrast-enhanced imaging (DCE) sequences (Figure 1). Univariate and multiple stepwise linear regression analysis were conducted to identify MRI features associated with histology score. All analyses were performed using Statistical Analysis System (SAS v 9.4). RESULTS: 99 prostate nodules in 29 patients were included. Median phenotypic scores by histology and MRI were comparable (2, IQR 2-3 vs. 2, IQR 2-4, respectively; p=0.63). Histology scores were positively associated with MRI scores on univariate analysis (p <0.0001). Multiple stepwise linear regression analysis showed apparent diffusion coefficient (ADC) low signal intensity and DCE wash-in to be positively associated with more stromal histology score, and ADC SD, DCE wash-out, and heterogeneous T2 texture to be negatively associated with more stromal histology score (Table 1). CONCLUSIONS: There is strong correlation between MRI features and the histologic phenotype of BPH nodules. MRI may provide a non-invasive method to determine underlying BPH nodule histology. Source of Funding: DK115477 (DWS) © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e395-e396 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Jessica Dai More articles by this author Tara Morgan More articles by this author Ramy Goueli More articles by this author Daniel Parrott More articles by this author Douglas Strand More articles by this author Daniel Costa More articles by this author Claus Roehrborn More articles by this author Jeffrey Gahan More articles by this author Expand All Advertisement Loading ...