Fetal Kidney Grafts and Organoids from Microminiature Pigs: Establishing a Protocol for Production and Long-Term Cryopreservation.

Fetal organs and organoids are important tools for studying organ development. Recently, porcine organs have garnered attention as potential organs for xenotransplantation because of their high degree of similarity to human organs. However, to meet the prompt demand for porcine fetal organs by patients and researchers, effective methods for producing, retrieving, and cryopreserving pig fetuses are indispensable. Therefore, in this study, to collect fetuses for kidney extraction, we employed cesarean sections to preserve the survival and fertility of the mother pig and a method for storing fetal kidneys by long-term cryopreservation. Subsequently, we evaluated the utility of these two methods. We confirmed that the kidneys of pig fetuses retrieved by cesarean section that were cryopreserved for an extended period could resume renal growth when grafted into mice and were capable of forming renal organoids. These results demonstrate the usefulness of long-term cryopreserved fetal pig organs and strongly suggest the effectiveness of our comprehensive system of pig fetus retrieval and fetal organ preservation, thereby highlighting its potential as an accelerator of xenotransplantation research and clinical innovation.

The powerful potential of amino acid menthyl esters for anti-inflammatory and anti-obesity therapies.

Our newly developed menthyl esters of valine and isoleucine exhibit anti-inflammatory properties beyond those of the well-known menthol in macrophages stimulated by lipopolysaccharide (LPS) and in a mouse model of colitis induced by sodium dextran sulfate. Unlike menthol, which acts primarily through the cold-sensitive TRPM8 channel, these menthyl esters displayed unique mechanisms that operate independently of this receptor. They readily penetrated target cells and efficiently suppressed LPS-stimulated tumour necrosis factor-alpha (Tnf) expression mediated by liver X receptor (LXR), a key nuclear receptor that regulates intracellular cholesterol and lipid balance. The menthyl esters showed affinity for LXR and enhanced the transcriptional activity through their non-competitive and potentially synergistic agonistic effect. This effect can be attributed to the crucial involvement of SCD1, an enzyme regulated by LXR, which is central to lipid metabolism and plays a key role in the anti-inflammatory response. In addition, we discovered that the menthyl esters showed remarkable efficacy in suppressing adipogenesis in 3T3-L1 adipocytes at the mitotic clonal expansion stage in an LXR-independent manner as well as in mice subjected to diet-induced obesity. These multiple capabilities of our compounds establish them as formidable allies in the fight against inflammation and obesity, paving the way for a range of potential therapeutic applications.

Novel Potential of Rose Essential Oil as a Powerful Plant Defense Potentiator.

Terpenoids, natural compounds released by plants, function to enhance plant defense. The aim of this study was to investigate the effects of terpenoid-enriched essential oils (EOs) on tomato plants. From the application of a highly diluted solution of 11 different EOs to potted tomato soil, our study showed that rose essential oil (REO), rich in ß-citronellol, played a crucial role in activating defense genes in tomato leaves. As a result, leaf damage caused by herbivores, such as Spodoptera litura and Tetranychus urticae, was significantly reduced. In addition, our results were validated in field trials, providing evidence that REO is an effective biostimulant for enhancing plant defense against pests. Notably, the REO solution also had the added benefit of attracting herbivore predators, such as Phytoseiulus persimilis. Our findings suggest a practical approach to promote organic tomato production that encourages environmentally friendly and sustainable practices.

Exploration of Preservation Methods for Utilizing Porcine Fetal-Organ-Derived Cells in Regenerative Medicine Research.

Human pluripotent stem cells have been employed in generating organoids, yet their immaturity compared to fetal organs and the limited induction of all constituent cell types remain challenges. Porcine fetal progenitor cells have emerged as promising candidates for co-culturing with human progenitor cells in regeneration and xenotransplantation research. This study focused on identifying proper preservation methods for porcine fetal kidneys, hearts, and livers, aiming to optimize their potential as cell sources. Extracted from fetal microminiature pigs, these organs were dissociated before and after cryopreservation-thawing, with subsequent cell quality evaluations. Kidney cells, dissociated and aggregated after vitrification in a whole-organ form, were successfully differentiated into glomeruli and tubules in vivo. In contrast, freezing hearts and livers before dissociation yielded suboptimal results. Heart cells, frozen after dissociation, exhibited pulsating heart muscle cells similar to non-frozen hearts. As for liver cells, we developed a direct tissue perfusion technique and successfully obtained highly viable liver parenchymal cells. Freezing dissociated liver cells, although inferior to their non-frozen counterparts, maintained the ability for colony formation. The findings of this study provide valuable insights into suitable preservation methods for porcine fetal cells from kidneys, hearts, and livers, contributing to the advancement of regeneration and xenotransplantation research.

Effects of a Gamified Agent-Based System for Personalized Elderly Care: Pilot Usability Study.

BACKGROUND: The global percentage of older people has increased significantly over the last decades. Information and communication technologies have become essential to develop and motivate them to pursue healthier ways of living. This paper examines a personalized coaching health care service designed to maintain living conditions and active aging among older people. Among the technologies the service includes, we highlight the use of both gamification and cognitive assistant technologies designed to support older people and an application combining a cognitive virtual assistant to directly interact with the older person and provide feedback on their current health condition and several gamification techniques to motivate the older person to stay engaged with the application and pursuit of healthier daily habits. OBJECTIVE: This pilot study aimed to investigate the feasibility and usability of a gamified agent-based system for older people and obtain preliminary results on the effectiveness of the intervention regarding physical activity health outcomes. METHODS: The study was designed as an intervention study comparing pre- and posttest results. The proposed gamified agent-based system was used by 12 participants over 7 days (1 week), and step count data were collected with access to the Google Fit application programming interface. Step count data after the intervention were compared with average step count data before the intervention (average daily values over a period of 4 weeks before the intervention). A　1-tailed Student t test was used to determine the relationship between the dependent and independent variables. Usability was measured using the System Usability Scale questionnaire, which was answered by 8 of the 12 participants in the study. RESULTS: The posttest results showed significant pre- to posttest changes (P=.30; 1-tailed Student t test) with a moderate effect size (Cohen d=0.65). The application obtained an average usability score of 78. CONCLUSIONS: The presented pilot was validated, showing the positive health effects of using gamification techniques and a virtual cognitive assistant. Additionally, usability metrics considered for this study confirmed high adherence and interest from most participants in the pilot.

Green leaf volatile sensory calcium transduction in Arabidopsis.

Plants perceive volatile organic compounds (VOCs) released by mechanically- or herbivore-damaged neighboring plants and induce various defense responses. Such interplant communication protects plants from environmental threats. However, the spatiotemporal dynamics of VOC sensory transduction in plants remain largely unknown. Using a wide-field real-time imaging method, we visualize an increase in cytosolic Ca2+ concentration ([Ca2+]cyt) in Arabidopsis leaves following exposure to VOCs emitted by injured plants. We identify two green leaf volatiles (GLVs), (Z)-3-hexenal (Z-3-HAL) and (E)-2-hexenal (E-2-HAL), which increase [Ca2+]cyt in Arabidopsis. These volatiles trigger the expression of biotic and abiotic stress-responsive genes in a Ca2+-dependent manner. Tissue-specific high-resolution Ca2+ imaging and stomatal mutant analysis reveal that [Ca2+]cyt increases instantly in guard cells and subsequently in mesophyll cells upon Z-3-HAL exposure. These results suggest that GLVs in the atmosphere are rapidly taken up by the inner tissues via stomata, leading to [Ca2+]cyt increases and subsequent defense responses in Arabidopsis leaves.

Successful reconstruction of the rat ureter by a syngeneic collagen tube with a cardiomyocyte sheet.

Introduction: Ureteral injuries require surgical intervention as they lead to loss of renal function. The current reconstructive techniques for long ureteral defects are problematic. Consequently, this study aimed to reconstruct the ureter in a rat model using subcutaneously prepared autologous collagen tubes (Biotubes). Methods: The lower ureter of LEW/SsNSlc rats was ligated to dilate the ureter to make anastomosis easier, and reconstruction was performed six days later by anastomosing the dilated ureter and bladder with a Biotube that was prepared subcutaneously in syngeneic rats. Some rats underwent left nephrectomy and ureter reconstruction simultaneously as negative controls to evaluate the effects of urine flow on patency. The other rats were divided into three groups as follows: a group in which the ureter was reconstructed with the Biotube alone, a group in which cardiomyocyte sheets made from the neonatal hearts of syngeneic rats were wrapped around the Biotube, and a group in which an adipose-derived stem cell sheets made from the inguinal fat of adult syngeneic rats were wrapped. Contrast-enhanced computed tomography and pathological evaluations were performed two weeks after reconstruction. Result: In the Biotube alone group, all tubes were occluded and hydronephrosis developed, whereas the urothelium regenerated beyond the anastomosis when the left kidney was not removed, suggesting that urothelial epithelial spread occurred with urinary flow. The patency of the ureteral lumen was obtained in some rats in the cardiomyocyte sheet covered group, whereas stricture or obstruction of the reconstructed ureter was observed in all rats in the other groups. Pathological evaluation revealed a layered urothelial structure in the cardiomyocyte sheet covered group, although only a small amount of cardiomyocyte sheets remained. Conclusion: Urinary flow may support the epithelial spread of the urothelium into the reconstructed ureter. Neonatal rat cardiomyocyte sheets supported the patency of the regenerated ureter with a layered urothelium.

Long-term viable chimeric nephrons generated from progenitor cells are a reliable model in cisplatin-induced toxicity.

Kidney organoids have shown promise as evaluation tools, but their in vitro maturity remains limited. Transplantation into adult mice has aided in maturation; however, their lack of urinary tract connection limits long-term viability. Thus, long-term viable generated nephrons have not been demonstrated. In this study, we present an approachable method in which mouse and rat renal progenitor cells are injected into the developing kidneys of neonatal mice, resulting in the generation of chimeric nephrons integrated with the host urinary tracts. These chimeric nephrons exhibit similar maturation to the host nephrons, long-term viability with excretion and reabsorption functions, and cisplatin-induced renal injury in both acute and chronic phases, as confirmed by single-cell RNA-sequencing. Additionally, induced human nephron progenitor cells differentiate into nephrons within the neonatal kidneys. Collectively, neonatal injection represents a promising approach for in vivo nephron generation, with potential applications in kidney regeneration, drug screening, and pathological analysis.

Structure-activity relationship of volatile compounds that induce defense-related genes in maize seedlings.

Volatile organic compounds mediate plant-to-plant communication, and plants receiving volatile cues can acquire greater defenses against attackers. It has been expected that volatiles are received by factors that eventually lead to the induction of defense-related gene expression; however, the nature of these factors remain unclear. Structure-activity relationship analysis of gene expression induction by volatiles should provide insights into the nature of these factors. We conducted a structure-activity relationship study using maize seedlings and (Z)-3-hexen-1-yl acetate (Z3HAC) as the lead compound. The acid portion of Z3HAC was not essential, and (Z)-3-hexen-1-ol (Z3HOL), which is formed after the hydrolysis of Z3HAC, is likely the structure essential for the upregulation of the genes. The double bond of Z3HOL is essential; however, its geometry is indistinguishable. Strict specificity was detected regarding the length of the methylene chain on the α- and ω-sides of the double bond, and therefore, the 3-hexen-1-ol structure was found to be the ultimate structure. This finding provides insight into the nature of the factors that interact with a volatile compound and subsequently activate signaling pathways, leading to the upregulation of a subset of defense genes.

General public's understanding of rare diseases and their opinions on medical resource allocation in Japan: a cross-sectional study.

BACKGROUND: Rare diseases (RDs) may impose a considerable financial burden on patients and their families. Public acceptance is essential to ensure sustainable public systems supporting RDs, especially in countries with universal healthcare coverage, such as Japan. This study aimed to explore the public's understanding of RDs and identify crucial factors associated with the public acceptance of prioritizing financial support for RDs in Japan. METHODS: An online questionnaire was sent to 131,220 Japanese residents aged 20-69 years. The items included in the questionnaire were general interest in medical science and medical care, general knowledge regarding RDs and health care systems, opinions on the cost of medical care, opinions on the research and development of RDs and common diseases, and individual characteristics. RESULTS: The responses of 11,019 respondents were analyzed. Several respondents agreed to partially cover the medication cost of adult and pediatric RDs (59.5% and 66.8%, respectively) with public funding. The major reasons for agreeing were the huge financial burden imposed on patients and their families, limited available treatment options, effects of RDs on the life planning of patients, and difficulties caused by RDs in the patient's social life. Furthermore, the respondents ranked RDs (56.0%) higher than common diseases (44.0%) for government funding for research and development. The reasons for supporting government-funded research and development for RDs included the lack of treatment options for numerous RDs (34.9%) and difficulty of studying RDs owing to the small number of researchers (25.9%). The chief reasons for supporting government-funded research and development for common diseases were the large number of affected patients (59.7%) and the possibility of more treatment options becoming available through the promotion of research and development (22.1%). CONCLUSIONS: The general public considers burdens associated with daily living or finance more than the epidemiological characteristics of RD while making funding decisions, demonstrating that rarity was less prioritized. A gap appears to exist between the general public and RD experts regarding the understanding of the epidemiological characteristics of RD and its thresholds. This gap should be bridged to ensure that prioritization of financial support for RDs is accepted by the society.

Dialysis-related Amyloidosis Presenting as a Fever of Unknown Origin: Symptoms and Management.

A 74-year-old woman with a 34-year history of hemodialysis presented with an intermittent fever, which later coincided with recurrent bilateral shoulder and hip joint pain. Imaging studies suggested amyloid arthropathy, which was histologically confirmed by a synovial biopsy. Increasing ß2-microglobulin clearance during dialysis alone attenuated the intermittent fever and joint pain, but the symptoms did not disappear until the administration of prednisolone 10 mg/day. Reported cases of dialysis-related amyloidosis with a fever imply that changing to blood purification methods with high ß2-microglobulin clearance is crucial for controlling the condition long-term, whereas concurrent use of anti-inflammatory agents promptly alleviates the symptoms.

Evaluation of the ability of human induced nephron progenitor cells to form chimeric renal organoids using mouse embryonic renal progenitor cells.

The number of patients with end-stage renal failure is increasing annually worldwide and the problem is compounded by a shortage of renal transplantation donors. In our previous research, we have shown that transplantation of renal progenitor cells into the nephrogenic region of heterologous fetuses can induce the development of nephrons. We have also developed transgenic mice in which specific renal progenitor cells can be removed by drugs. By combining these two technologies, we have succeeded in generating human-mouse chimeric kidneys in fetal mice. We hope to apply these technologies to regenerative medicine. The quality of nephron progenitor cells (NPCs) derived from human pluripotent stem cells is important for the generation of chimeric kidneys, but there is currently no simple evaluation system for the chimerogenic potential of human NPCs. In this study, we focused on the fact that the re-aggregation of mouse renal progenitor cells can be used for nephron formation, even when merged into single cells. First, we examined the conditions under which nephron formation is likely to occur in mice during re-aggregation. Next, to improve the differentiation potential of human NPCs derived from pluripotent stem cells, NPCs were sorted using Integrin subunit alpha 8 (ITGA8). Finally, we demonstrated chimera formation between different species by mixing mouse cells with purified, selectively-induced human NPCs under optimum conditions. We observed these chimeric organoids at different time points to learn about these human-mouse chimeric structures at various stages of renal development. We found that the rate of chimera formation was affected by the purity of the human NPCs and the cell ratios used. We demonstrated that chimeric nephrons can be generated using a simple model, even between distant species. We believe that this admixture of human and mouse renal progenitor cells is a promising technology with potential application for the evaluation of the chimera formation abilities of NPCs.

Possible contribution of phosphate to the pathogenesis of chronic kidney disease in dolphins.

This study aimed to investigate whether phosphate contributes to the pathogenesis of chronic kidney disease (CKD) in dolphins. Renal necropsy tissue of an aged captive dolphin was analyzed and in vitro experiments using cultured immortalized dolphin proximal tubular (DolKT-1) cells were performed. An older dolphin in captivity died of myocarditis, but its renal function was within the normal range until shortly before death. In renal necropsy tissue, obvious glomerular and tubulointerstitial changes were not observed except for renal infarction resulting from myocarditis. However, a computed tomography scan showed medullary calcification in reniculi. Micro area X-ray diffractometry and infrared absorption spectrometry showed that the calcified areas were primarily composed of hydroxyapatite. In vitro experiments showed that treatment with both phosphate and calciprotein particles (CPPs) resulted in cell viability loss and lactate dehydrogenase release in DolKT-1 cells. However, treatment with magnesium markedly attenuated this cellular injury induced by phosphate, but not by CPPs. Magnesium dose-dependently decreased CPP formation. These data support the hypothesis that continuous exposure to high phosphate contributes to the progression of CKD in captive-aged dolphins. Our data also suggest that phosphate-induced renal injury is mediated by CPP formation in dolphins, and it is attenuated by magnesium administration.

Cryopreservation of Fetal Porcine Kidneys for Xenogeneic Regenerative Medicine.

Kidney xenotransplantation has been attracting attention as a treatment option for end-stage renal disease. Fetal porcine kidneys are particularly promising grafts because they can reduce rejection through vascularization from host vessels. We are proposing xenogeneic regenerative medicine using fetal porcine kidneys injected with human nephron progenitor cells. For clinical application, it is desirable to establish reliable methods for the preservation and quality assessment of grafts. We evaluated the differentiation potency of vitrified porcine fetal kidneys compared with nonfrozen kidneys, using an in vivo differentiation model. Fetal porcine kidneys connected to the bladder were frozen via vitrification and stored in liquid nitrogen. Several days later, they were thawed and transplanted under the retroperitoneum of immunocompromised mice. After 14 days, the frozen kidneys grew and differentiated into mature nephrons, and the findings were comparable to those of nonfrozen kidneys. In conclusion, we demonstrated that the differentiation potency of vitrified fetal porcine kidneys could be evaluated using this model, thereby providing a practical protocol to assess the quality of individual lots.

Identification of a tomato UDP-arabinosyltransferase for airborne volatile reception.

Volatiles from herbivore-infested plants function as a chemical warning of future herbivory for neighboring plants. (Z)-3-Hexenol emitted from tomato plants infested by common cutworms is taken up by uninfested plants and converted to (Z)-3-hexenyl ß-vicianoside (HexVic). Here we show that a wild tomato species (Solanum pennellii) shows limited HexVic accumulation compared to a domesticated tomato species (Solanum lycopersicum) after (Z)-3-hexenol exposure. Common cutworms grow better on an introgression line containing an S. pennellii chromosome 11 segment that impairs HexVic accumulation, suggesting that (Z)-3-hexenol diglycosylation is involved in the defense of tomato against herbivory. We finally reveal that HexVic accumulation is genetically associated with a uridine diphosphate-glycosyltransferase (UGT) gene cluster that harbors UGT91R1 on chromosome 11. Biochemical and transgenic analyses of UGT91R1 show that it preferentially catalyzes (Z)-3-hexenyl ß-D-glucopyranoside arabinosylation to produce HexVic in planta.

Biosynthesis of dillapiole/apiole in dill (Anethum graveolens): characterization of regioselective phenylpropene O-methyltransferase.

The phenylpropene volatiles dillapiole and apiole impart one of the characteristic aromas of dill (Anethum graveolens) weeds. However, very few studies have been conducted to investigate the chemical composition of volatile compounds from different developmental stages and plant parts of A. graveolens. In this study, we examined the distribution of volatile phenylpropenes, including dillapiole, in dill plants at various developmental stages. We observed that young dill seedlings accumulate high levels of dillapiole and apiole, whereas a negligible proportion was found in the flowering plants and dry seeds. Based on transcriptomics and co-expression approaches with phenylpropene biosynthesis genes, we identified dill cDNA encoding S-adenosyl-L-methionine-dependent O-methyltransferase 1 (AgOMT1), an enzyme that can convert 6- and 2-hydroxymyristicin to dillapiole and apiole, respectively, via the methylation of the ortho-hydroxy group. The AgOMT1 protein shows an apparent Km value of 3.5 µm for 6-hydroxymyristicin and is 75% identical to the anise (Pimpinella anisum) O-methyltransferase (PaAIMT1) that can convert isoeugenol to methylisoeugenol via methylation of the hydroxy group at the para-position of the benzene ring. AgOMT1 showed a preference for 6-hydroxymyristicin, whereas PaAIMT1 displayed a large preference for isoeugenol. In vitro mutagenesis experiments demonstrated that substituting only a few residues can substantially affect the substrate specificity of these enzymes. Other plants belonging to the Apiaceae family contained homologous O-methyltransferase (OMT) proteins highly similar to AgOMT1, converting 6-hydroxymyristicin to dillapiole. Our results indicate that apiaceous phenylpropene OMTs with ortho-methylating activity evolved independently of phenylpropene OMTs of other plants and the enzymatic function of AgOMT1 and PaAIMT1 diverged recently.

Association between C-Reactive Protein Levels and Functional Disability in the General Older-Population: The Takashima Study.

AIMS: High-sensitivity C-reactive protein (hsCRP) associates with atherosclerotic diseases such as stroke. However, previous results on the association between hsCRP levels and functional disability were controversial. METHODS: We analyzed 2,610 men and women who did not exhibit functional disability or death within the first 3 years of the baseline survey and those aged 65 years or older at the end of follow-up. The levels of hsCRP were assessed using latex agglutination assay at baseline survey from 2006 to 2014. Functional disability was followed up using the long-term care insurance (LTCI) program until November 1, 2019. Functional disability was defined as a new LTCI program certification. Cox proportional hazards model with competing risk analysis for death was used to evaluate the association between hsCRP levels and future functional disability. RESULTS: During a 9-year follow-up period, we observed 328 cases of functional disability and 67 deaths without prior functional disability incidence. The multivariable-adjusted hazard ratio (HR, 95% confidence interval [CI]) of functional disability in log-transferred hsCRP levels was 1.43 (1.22-1.67) in men and 0.97 (0.81-1.15) in women. When hsCRP level was analyzed as a categorical variable, low hsCRP levels (＜1.0 mg/l) as the reference, the multivariable-adjusted HR (95% CI) of functional disability in high hsCRP levels (≥ 3.0 mg/l) was 2.37 (1.56-3.62). Similar results were observed when stratified by sex, but it was not significant in women. CONCLUSIONS: This study demonstrates that low-grade systemic inflammation to assess hsCRP might predict the future incidence of functional disability, especially in men.

Coprinopsis cinerea dioxygenase is an oxygenase forming 10(S)-hydroperoxide of linoleic acid, essential for mushroom alcohol, 1-octen-3-ol, synthesis.

1-Octen-3-ol is a volatile oxylipin found ubiquitously in Basidiomycota and Ascomycota. The biosynthetic pathway forming 1-octen-3-ol from linoleic acid via the linoleic acid 10(S)-hydroperoxide was characterized 40 years ago in mushrooms, yet the enzymes involved are not identified. The dioxygenase 1 and 2 genes (Ccdox1 and Ccdox2) in the mushroom Coprinopsis cinerea contain an N-terminal cyclooxygenase-like heme peroxidase domain and a C-terminal cytochrome P450-related domain. Herein, we show that recombinant CcDOX1 is responsible for dioxygenation of linoleic acid to form the 10(S)-hydroperoxide, the first step in 1-octen-3-ol synthesis, whereas CcDOX2 conceivably forms linoleic acid 8-hydroperoxide. We demonstrate that KO of the Ccdox1 gene suppressed 1-octen-3-ol synthesis, although added linoleic acid 10(S)-hydroperoxide was still efficiently converted. The P450-related domain of CcDOX1 lacks the characteristic Cys heme ligand and the evidence indicates that a second uncharacterized enzyme converts the 10(S)-hydroperoxide to 1-octen-3-ol. Additionally, we determined the gene KO strain (ΔCcdox1) was less attractive to fruit fly larvae, while the feeding behavior of fungus gnats on ΔCcdox1 mycelia showed little difference from that on the mycelia of the WT strain. The proliferation of fungivorous nematodes on ΔCcdox1 mycelia was similar to or slightly worse than that on WT mycelia. Thus, 1-octen-3-ol seems to be an attractive compound involved in emitter-receiver ecological communication in mushrooms.

CRISPR/Cas9-mediated disruption of ALLENE OXIDE SYNTHASE results in defective 12-oxo-phytodienoic acid accumulation and reduced defense against spider mite (Tetranychus urticae) in liverwort (Marchantia polymorpha).

Allene oxide synthase (AOS) is a key enzyme involved in the biosynthesis of 12-oxo-phytodienoic acid (OPDA) and jasmonic acid and plays an important role in plant defense against herbivore attacks. In the liverwort, Marchantia polymorpha, we previously identified cytosol-type MpAOS1 and chloroplast-type MpAOS2 that show AOS activities. However, there is no direct evidence to show the subcellular localization of MpAOSs and their contribution to plant defense via OPDA production in M. polymorpha. In this study, we generated M. polymorpha mutants, with the MpAOS1 and MpAOS2 genes disrupted via CRISPR/Cas9-mediated genome editing; the loss of OPDA production was analyzed in double-knockout mutants. On AOS mutants, the survival rate and oviposition of spider mites (Tetranychus urticae) increased relative to those on wild-type plants. Overall, these findings suggest that defense systems via OPDA-signaling pathways in response to spider mites have been established in M. polymorpha.

Green Leaf Volatiles-The Forefront of Plant Responses Against Biotic Attack.

Green leaf volatiles (GLVs) are six-carbon volatile oxylipins ubiquitous in vascular plants. GLVs are produced from acyl groups in the biological membranes via oxygenation by a pathway-specific lipoxygenase (LOX) and a subsequent cleavage reaction by hydroperoxide lyase. Because of the universal distribution and ability to form GLVs, they have been anticipated to play a common role in vascular plants. While resting levels in intact plant tissues are low, GLVs are immediately synthesized de novo in response to stresses, such as insect herbivory, that disrupt the cell structure. This rapid GLV burst is one of the fastest responses of plants to cell-damaging stresses; therefore, GLVs are the first plant-derived compounds encountered by organisms that interact with plants irrespective of whether the interaction is competitive or friendly. GLVs should therefore be considered important mediators between plants and organisms that interact with them. GLVs can have direct effects by deterring herbivores and pathogens as well as indirect effects by attracting predators of herbivores, while other plants can recruit them to prepare their defenses in a process called priming. While the beneficial effects provided to plants by GLVs are often less dramatic and even complementary, the buildup of these tiny effects due to the multiple functions of GLVs can amass to levels that become substantially beneficial to plants. This review summarizes the current understanding of the spatiotemporal resolution of GLV biosynthesis and GLV functions and outlines how GLVs support the basic health of plants.