Identification of miRNA858 long-loop precursors in seed plants.

MicroRNAs (miRNAs) are a class of nonprotein-coding short transcripts that provide a layer of post-transcriptional regulation essential to many plant biological processes. MiR858, which targets the transcripts of MYB transcription factors, can affect a range of secondary metabolic processes. Although miR858 and its 187-nt precursor have been well studied in Arabidopsis (Arabidopsis thaliana), a systematic investigation of miR858 precursors and their functions across plant species is lacking due to a problem in identifying the transcripts that generate this subclass. By re-evaluating the transcript of miR858 and relaxing the length cut-off for identifying hairpins, we found in kiwifruit (Actinidia chinensis) that miR858 has long-loop hairpins (1,100 to 2,100 nt), whose intervening sequences between miRNA generating complementary sites were longer than all previously reported miRNA hairpins. Importantly, these precursors of miR858 containing long-loop hairpins (termed MIR858L) are widespread in seed plants including Arabidopsis, varying between 350 and 5,500 nt. Moreover, we showed that MIR858L has a greater impact on proanthocyanidin and flavonol levels in both Arabidopsis and kiwifruit. We suggest that an active MIR858L-MYB regulatory module appeared in the transition of early land plants to large upright flowering plants, making a key contribution to plant secondary metabolism.

Restricted responses of AcMYB68 and AcERF74/75 enhanced waterlogging tolerance in kiwifruit.

Most of kiwifruit cultivars (e.g. Actinidia chinensis cv. Donghong, "DH") were sensitive to waterlogging, thus, waterlogging resistant rootstocks (e.g. Actinidia valvata Dunn, "Dunn") were widely used for kiwifruit industry. Those different species provided ideal materials to understand the waterlogging responses in kiwifruit. Compared to the weaken growth and root activities in "DH", "Dunn" maintained the relative high root activities under the prolonged waterlogging. Based on comparative analysis, transcript levels of pyruvate decarboxylase (PDCs) and alcohol dehydrogenase (ADHs) showed significantly difference between these two species. Both PDCs and ADHs had been significantly increased by waterlogging in "DH", while they were only limitedly triggered by 2 days stress and subsided during the prolonged waterlogging in "Dunn". Thus, 19 differentially expressed transcript factors (DETFs) had been isolated using weighted gene co-expression network analysis combined with transcriptomics and transcript levels of PDCs and ADHs in waterlogged "DH". Among these DETFs, dual luciferase and electrophoretic mobility shift assays indicated AcMYB68 could bind to and trigger the activity of AcPDC2 promoter. The stable over-expression of AcMYB68 significantly up-regulated the transcript levels of PDCs but inhibited the plant growth, especially the roots. Moreover, the enzyme activities of PDC in 35S::AcMYB68 were significantly enhanced during the waterlogging response than that in wild type plants. Most interestingly, comparative analysis indicated that the expression patterns of AcMYB68 and the previously characterized AcERF74/75 (the direct regulator on ADHs) either showed no responses (AcMYB68 and AcERF74) or very limited response (AcERF75) in "Dunn". Taken together, the restricted responses of AcMYB68 and AcERF74/75 in "Dunn" endow its waterlogging tolerance.

AcHZP45 is a repressor of chlorophyll biosynthesis and activator of chlorophyll degradation in kiwifruit.

The degradation of chlorophyll during fruit development is essential to reveal a more 'ripe' color that signals readiness to wild dispersers of seeds and the human consumer. Here, comparative biochemical analysis of developing fruit of Actinidia deliciosa cv. Xuxiang ('XX', green-fleshed) and Actinidia chinensis cv. Jinshi No.1 ('JS', yellow-fleshed) indicated that variation in chlorophyll content is the major contributor to differences in flesh color. Four differentially expressed candidate genes were identified: the down-regulated genes AcCRD1 and AcPOR1 involved in chlorophyll biosynthesis, and the up-regulated genes AcSGR1 and AcSGR2 driving chlorophyll degradation. Prochlorophyllide and chlorophyllide, the metabolites produced by AcCRD1 and AcPOR1, progressively reduced in 'JS', but not in 'XX', indicating that chlorophyll biosynthesis was less active in yellow-fleshed fruit. AcSGR1 and AcSGR2 were verified to be involved in chlorophyll degradation, using both transient expression in tobacco and stable overexpression in kiwifruit. Furthermore, a homeobox-leucine zipper (HD-Zip II), AcHZP45, showed significantly increased expression during 'JS' fruit ripening, which led to both repressed expression of AcCRD1 and AcPOR1 and activated expression of AcSGR1 and AcSGR2. Collectively, the present study indicated that different dynamics of chlorophyll biosynthesis and degradation coordinate the changes in chlorophyll content in kiwifruit flesh, which are orchestrated by the key transcription factor AcHZP45.

A dramatic decline in fruit citrate induced by mutagenesis of a NAC transcription factor, AcNAC1.

Citrate is a common primary metabolite which often characterizes fruit flavour. The key regulators of citrate accumulation in fruit and vegetables are poorly understood. We systematically analysed the dynamic profiles of organic acid components during the development of kiwifruit (Actinidia spp.). Citrate continuously accumulated so that it became the predominate contributor to total acidity at harvest. Based on a co-expression network analysis using different kiwifruit cultivars, an Al-ACTIVATED MALATE TRANSPORTER gene (AcALMT1) was identified as a candidate responsible for citrate accumulation. Electrophysiological assays using expression of this gene in Xenopus oocytes revealed that AcALMT1 functions as a citrate transporter. Additionally, transient overexpression of AcALMT1 in kiwifruit significantly increased citrate content, while tissues showing higher AcALMT1 expression accumulated more citrate. The expression of AcALMT1 was highly correlated with 17 transcription factor candidates. However, dual-luciferase and EMSA assays indicated that only the NAC transcription factor, AcNAC1, activated AcALMT1 expression via direct binding to its promoter. Targeted CRISPR-Cas9-induced mutagenesis of AcNAC1 in kiwifruit resulted in dramatic declines in citrate levels while malate and quinate levels were not substantially affected. Our findings show that transcriptional regulation of a major citrate transporter, by a NAC transcription factor, is responsible for citrate accumulation in kiwifruit, which has broad implications for other fruits and vegetables.

The red flesh of kiwifruit is differentially controlled by specific activation-repression systems.

Anthocyanins are visual cues for pollination and seed dispersal. Fruit containing anthocyanins also appeals to consumers due to its appearance and health benefits. In kiwifruit (Actinidia spp.) studies have identified at least two MYB activators of anthocyanin, but their functions in fruit and the mechanisms by which they act are not fully understood. Here, transcriptome and small RNA high-throughput sequencing were used to comprehensively identify contributors to anthocyanin accumulation in kiwifruit. Stable overexpression in vines showed that both 35S::MYB10 and MYB110 can upregulate anthocyanin biosynthesis in Actinidia chinensis fruit, and that MYB10 overexpression resulted in anthocyanin accumulation which was limited to the inner pericarp, suggesting that repressive mechanisms underlie anthocyanin biosynthesis in this species. Furthermore, motifs in the C-terminal region of MYB10/110 were shown to be responsible for the strength of activation of the anthocyanic response. Transient assays showed that both MYB10 and MYB110 were not directly cleaved by miRNAs, but that miR828 and its phased small RNA AcTAS4-D4(-) efficiently targeted MYB110. Other miRNAs were identified, which were differentially expressed between the inner and outer pericarp, and cleavage of SPL13, ARF16, SCL6 and F-box1, all of which are repressors of MYB10, was observed. We conclude that it is the differential expression and subsequent repression of MYB activators that is responsible for variation in anthocyanin accumulation in kiwifruit species.

An ethylene-hypersensitive methionine sulfoxide reductase regulated by NAC transcription factors increases methionine pool size and ethylene production during kiwifruit ripening.

Ethylene plays an important role in regulating fruit ripening by triggering dynamic changes in expression of ripening-associated genes, but the functions of many of these genes are still unknown. Here, a methionine sulfoxide reductase gene (AdMsrB1) was identified by transcriptomics-based analysis as the gene most responsive to ethylene treatment in ripening kiwifruit. The AdMsrB1 protein exhibits a stereospecific activity toward the oxidative stress-induced R enantiomer of methionine sulfoxide (MetSO), reducing it to methionine (Met). Stable overexpression of AdMsrB1 in kiwifruit significantly increased the content of free Met and 1-aminocyclopropane-1-carboxylic acid (ACC), the immediate precursor of ethylene, and increased ethylene production. Dual-luciferase assays indicated that the AdMsrB1 promoter was not directly upregulated by ethylene treatment but was modulated by two ethylene-inducible NAM/ATAF/CUC transcription factors (AdNAC2 and AdNAC72) that bind directly to the AdMsrB1 promoter. Overexpression of AdNAC72 in kiwifruit not only enhanced AdMsrB1 expression, but also increased free Met and ACC content and ethylene production rates. This finding establishes an unexpected regulatory loop that enhances ethylene production and the concentration of its biosynthetic intermediates.

Genome-wide analysis of coding and non-coding RNA reveals a conserved miR164-NAC regulatory pathway for fruit ripening.

Kiwifruit (Actinidia spp.) is a climacteric fruit with high sensitivity to ethylene, influenced by multiple ethylene-responsive structural genes and transcription factors. However, the roles of other post-transcriptional regulators (e.g. miRNAs) necessary for ripening remain elusive. High-throughput sequencing sRNAome, degradome and transcriptome methods were used to identify further contributors to ripening control in the kiwifruit (A. deliciosa cv 'Hayward'). Two NAM/ATAF/CUC domain transcription factors (AdNAC6 and AdNAC7), both predicted targets for miR164, showed significant upregulation by exogenous ethylene. Gene expression analysis and luciferase reporter assays indicated that Ade-miR164 and one of its precursor miRNAs (Ade-MIR164b) were repressed by ethylene treatment and negatively correlated with AdNAC6/7 expression. Subsequent analysis indicated that both AdNAC6 and AdNAC7 proteins are transcriptional activators and physically bind the promoters of AdACS1 (1-aminocyclopropane-1-carboxylate synthase), AdACO1 (1-aminocyclopropane-1-carboxylic acid oxidase), AdMAN1 (endo-ß-mannanase) and AaTPS1 (terpene synthase). Moreover, subcellular analysis indicated that the location of the AdNAC6/7 proteins was influenced by Ade-miR164. Multiple omics-based approaches revealed a novel regulatory link for fruit ripening that involved ethylene-miR164-NAC. The regulatory pathway for miR164-NAC is present in various fruit (e.g. Rosaceae fruit, citrus, grape), with implications for fruit ripening regulation.

Transcriptome Analysis Identifies a Zinc Finger Protein Regulating Starch Degradation in Kiwifruit.

Ripening, including softening, is a critical factor in determining the postharvest shelf-life of fruit and is controlled by enzymes involved in cell wall metabolism, starch degradation, and hormone metabolism. Here, we used a transcriptomics-based approach to identify transcriptional regulatory components associated with texture, ethylene, and starch degradation in ripening kiwifruit (Actinidia deliciosa). Twelve differentially expressed structural genes, including seven involved in cell wall metabolism, four in ethylene biosynthesis, and one in starch degradation, and 14 transcription factors (TFs) induced by exogenous ethylene treatment and inhibited by the ethylene signaling inhibitor 1-methylcyclopropene were identified as changing in transcript levels during ripening. Moreover, analysis of the regulatory effects of differentially expressed genes identified a zinc finger TF, DNA BINDING WITH ONE FINGER (AdDof3), which showed significant transactivation on the AdBAM3L (ß-amylase) promoter. AdDof3 interacted physically with the AdBAM3L promoter, and stable overexpression of AdBAM3L resulted in lower starch content in transgenic kiwifruit leaves, suggesting that AdBAM3L is a key gene for starch degradation. Moreover, transient overexpression analysis showed that AdDof3 up-regulated AdBAM3L expression in kiwifruit. Thus, transcriptomics analysis not only allowed the prediction of some ripening-regulating genes but also facilitated the characterization of a TF, AdDof3, and a key structural gene, AdBAM3L, in starch degradation.

Joint Antiangiogenic Effect of ATN-161 and Anti-VEGF Antibody in a Rat Model of Early Wet Age-Related Macular Degeneration.

The wet form of age-related macular degeneration (AMD) is a leading cause of blindness among elderly Americans and is characterized by abnormal vessel growth, termed choroidal neovascularization (CNV). Integrin α5ß1 is a transmembrane receptor that binds matrix macromolecules and proteinases to stimulate angiogenesis. We recently demonstrated that integrin α5ß1 plays a critical role in the development of choroidal neovascularization. In this study, we determined the role and underlying mechanisms of integrin α5ß1 in angiogenesis in human choroidal endothelial cells and evaluated the antiangiogenic effects of delivering a combination therapy of ATN-161, an integrin α5ß1 inhibitor, and an anti-VEGF monoclonal antibody to rats with laser-induced CNV. Vascular endothelial growth factor (VEGF) is a signaling protein that stimulates vasculogenesis and angiogenesis through a pathway that is distinct from the integrin α5ß1 signaling pathway. Our results indicate that fibronectin binds to integrin α5ß1 and synergizes VEGF-induced angiogenesis via two independent signaling pathways, FN/integrin α5ß1/FAK/ERK1/2 and FN/integrin α5ß1/FAK/AKT. Integrin α5 knockdown by shRNA inhibits endothelial cell migration, tube formation, and proliferation, while ATN-161 only partially decreases integrin α5 function. Treatment with ATN-161 combined with anti-VEGF antibody showed joint effects in attenuating angiogenesis. In summary, our results provide the first evidence for the mechanisms by which integrin α5ß1 is involved in ocular pathological neovascularization in vivo, suggesting that dual inhibition of integrin α5ß1 and VEGF may be a promising novel therapeutic strategy for CNV in wet AMD.

[Detection of macular foveal by optical coherence tomography and its influence on results of measurement of central retina thickness].

OBJECTIVE: To detect macular foveal by Cirrus(TM) HD-OCT using the post acquisition fovea detection and to study its influence on the results of measurement of central retina thickness (CRT). METHODS: In this retrospectively studies, the 512×128 cube scans from 50 eyes of normal subjects and 50 eyes of macular edema patients were analyzed. Three methods for the foveal detection were used, the scan center (SC), the automated detected foveal (AF) and the manually identified foveal (MF). The foveal detected by MF was set as the reference. Radial distances from SC and AF to MF were calculated. Subfields retinal thickness acquired from different groups using different foveal detection methods were compared by paired Student's t test for normal data or Wilcoxon-Mann-Whitney for non-normal data. RESULTS: For normal subjects, it is reliable determining the foveal by special tomography features. The means of the radial distance from the MF was (35.0 ± 23.0) µm in scan center group and was (6.0 ± 9.0) µm in automated center (t = -3.732, P < 0.05). The average CRT difference between the SC and MF groups was (7.4 ± 10.4) µm. The median difference between the AF and MF groups was 0 µm (0 to 3), which is significantly less than that between the SC and MF groups (Z = -2.956, P < 0.05). In subjects with macular edema, the means of the radial offset was (59.0 ± 26.0) µm in SC group and was (34.0 ± 23.0) µm in AF group (t = -4.555, P < 0.05). The average CRT difference between the SC and MF groups was (28.0 ± 36.0) µm, which was not significantly greater than the difference between the AF and MF groups (23.0 ± 31.0) µm in macular edema eyes. CONCLUSIONS: Post acquisition detection of foveal reduces the radial offset to the real fovea, and may improve the reproducibility and reliability of the central retinal thickness quantification using spectral domain OCT in normal subjects.

Molecular basis of the formation and removal of fruit astringency.

Astringency is a dry puckering mouthfeel mainly generated by the binding of tannins with proteins in the mouth. Tannins confer benefits such as resistance to biotic stresses and have antioxidant activity, and moderate concentrations of tannins can improve the flavor of fruits or their products. However, fruits with high contents of tannins have excessive astringency, which is undesirable. Thus, the balance of astringency formation and removal is extremely important for human consumption of fruit and fruit-based products. In recent years, the understanding of fruit astringency has moved beyond the biochemical aspects to focus on the genetic characterization of key structural genes and their transcriptional regulators that cause astringency. This article provides an overview of astringency formation and evaluation. We summarize the methods of astringency regulation and strategies and mechanisms for astringency removal, and discuss perspectives for future exploration and modulation of astringency for fruit quality improvement.

Transcriptional and post-transcriptional regulation of ethylene biosynthesis by exogenous acetylsalicylic acid in kiwifruit.

Levels of ethylene, implicated in the induction of fruit ripening in a diverse array of plants, are influenced by genetic and environmental factors, such as other plant hormones. Among these, salicylic acid (SA) and its derivative, acetylsalicylic acid (ASA), have been demonstrated to inhibit ethylene biosynthesis in fruit, yet the underlying regulatory mechanisms remain elusive. Here, we showed that treatment with exogenous ASA dramatically reduced ethylene production, as well as activities of ACC synthase (ACS) and ACC oxidase (ACO), in kiwifruit tissues. Comparative transcriptome analysis indicated the differential expression of ethylene biosynthetic genes (AdACS1/2 and AdACO5). A screen of transcription factors indicated that AdERF105L and AdWRKY29 were ASA-responsive regulators of AdACS1/2 and AdACO5, respectively. In addition to these genes, AdACS3 and AdACO3 were abundantly expressed in both ASA-treated and control tissues. AdACS3 protein was phosphorylated and stabilized by AdMPK16, a mitogen-activated protein kinase, while AdACO3 activity was enhanced by AdAP, an aspartic peptidase. Exogenous ASA downregulated AdMPK16 and AdAP, thereby influencing ethylene biosynthesis at a post-transcriptional level. These findings led us to propose a multidimensional system for inhibition of ethylene biosynthesis by ASA, inducing differential expression of some ethylene biosynthesis genes, as well as differential effects on protein activity on other targets.

Consensus co-expression network analysis identifies AdZAT5 regulating pectin degradation in ripening kiwifruit.

INTRODUCTION: Cell wall degradation and remodeling is the key factor causing fruit softening during ripening. OBJECTIVES: To explore the mechanism underlying postharvest cell wall metabolism, a transcriptome analysis method for more precious prediction on functional genes was needed. METHODS: Kiwifruits treated by ethylene (a conventional and effective phytohormone to accelerate climacteric fruit ripening and softening as kiwifruits) or air were taken as materials. Here, Consensus Coexpression Network Analysis (CCNA), a procedure evolved from Weighted Gene Co-expression Network Analysis (WGCNA) package in R, was applied and generated 85 consensus clusters from twelve transcriptome libraries. Advanced and comprehensive modifications were achieved by combination of CCNA and WGCNA with introduction of physiological traits, including firmness, cell wall materials, cellulose, hemicellulose, water soluble pectin, covalent binding pectin and ionic soluble pectin. RESULTS: As a result, six cell wall metabolisms related structural genes AdGAL1, AdMAN1, AdPL1, AdPL5, Adß-Gal5, AdPME1 and four transcription factors AdZAT5, AdDOF3, AdNAC083, AdMYBR4 were identified as hub candidate genes for pectin degradation. Dual-luciferase system and electrophoretic mobility shift assays validated that promoters of AdPL5 and Adß-Gal5 were recognized and trans-activated by transcription factor AdZAT5. The relatively higher enzyme activities of PL and ß-Gal were observed in ethylene treated kiwifruit, further emphasized the critical roles of these two pectin related genes for fruit softening. Moreover, stable transient overexpression AdZAT5 in kiwifruit significantly enhanced AdPL5 and Adß-Gal5 expression, which confirmed the in vivo regulations between transcription factor and pectin related genes. CONCLUSION: Thus, modification and application of CCNA would be powerful for the precious phishing the unknown regulators. It revealed that AdZAT5 is a key factor for pectin degradation by binding and regulating effector genes AdPL5 and Adß-Gal5.

Transcription factors AcERF74/75 respond to waterlogging stress and trigger alcoholic fermentation-related genes in kiwifruit.

Kiwifruit plants have a fleshy, shallow root system which is sensitive to waterlogging stress, which results in a decrease in crop yield or even plants death. Although the waterlogging stress responses in kiwifruit have attracted much attention, the underlying molecular mechanism remains unclear. In this study, waterlogging led to drastic inhibition of root growth of 'Donghong' kiwifruit (Actinidia chinensis) plants grown in vitro, which was accompanied by significant elevation of endogenous acetaldehyde and ethanol contents. RNA-seq of roots of plants waterlogged for 0, 1 and 2 days revealed that a total of 149 genes were up- or down-regulated, including seven biosynthetic genes related to the glycolysis/gluconeogenesis pathway and 10 transcription factors. Analyses with real-time PCR, dual-luciferase assays and EMSA demonstrated that AcERF74 and AcERF75, two members of the ERF-VII subfamily, directly upregulated AcADH1 (alcohol dehydrogenase). Moreover, the overexpression of AcERF74/75 in transgenic calli resulted in dramatic increase of endogenous ethanol contents through the triggering of AcADH1 and AcADH2 expression. Although the AcPDC2 (pyruvate decarboxylase) expression was also enhanced in transgenic lines, the endogenous acetaldehyde contents showed no significant changes. These results illustrated that AcERF74/75 are two transcriptional activators on alcoholic fermentation related genes and are responsive to waterlogging stress in kiwifruit.

Transcriptome Analysis Revealed the Roles of Carbohydrate Metabolism on Differential Acetaldehyde Production Capacity in Persimmon Fruit in Response to High-CO2 Treatment.

Persimmon (Diospyros kaki Thunb.) fruit is unique due to the continuous accumulation of soluble tannins during fruit development in most cultivars, which causes undesired astringency. High-CO2 treatment was the most effective widely used method for astringency removal. However, differential effects of high-CO2 treatment between cultivars were observed and the molecular basis remained inclusive. Previously, one cultivar ("Luoyangfangtianshengshi," LYFTSS) showed rapid deastringency, while two cultivars ("Shijiazhuanglianhuashi," SJZLHS; "Laopige," LPG) showed slow deastringency in response to high-CO2 (95% CO2) treatment. In this study, the metabolites (acetaldehyde and ethanol) related to deastringency were further analyzed and both acetaldehyde and ethanol were higher in SJZLHS and LYFTSS than that in LPG, where acetaldehyde was undetectable. Based on the RNA-seq data, the weighted gene coexpression network analysis (WGCNA) revealed that one module, comprised of 1773 unigenes, significantly correlated with the contents of acetaldehyde and ethanol (P < 0.001). Further analysis based on the acetaldehyde metabolism pathway indicated that the differentially expressed structural genes, including previously characterized DkADH and DkPDC and also their upstream members (e.g., PFK, phosphofructokinase), showed positive correlations with acetaldehyde production. Quantitative analysis of the precursor substances indicated that sucrose, glucose, and fructose exhibited limited differences between cultivar except for malic acid. However, the content of malic acid is much less than the total soluble sugar content. To verify the correlations between these genes and acetaldehyde production, the fruit from 14 more cultivars were collected and treated with high CO2. After the treatment, acetaldehyde contents in different cultivars ranked in 30.4-255.5 µg/g FW. Real-time polymerase chain reaction (PCR) and correlation analysis indicated that the EVM0002315 (PFK) gene, belonging to carbohydrate metabolism, was significantly correlated with acetaldehyde content in fruit. Thus, it could be proposed that the differentially expressed carbohydrate metabolism related genes (especially PFK) are the basis for the variance of acetaldehyde production among different persimmon cultivars.

Methyl Jasmonate Enhances Ethylene Synthesis in Kiwifruit by Inducing NAC Genes That Activate ACS1.

Cross-talk between various hormones is important in regulating many aspects of plant growth, development, and senescence, including fruit ripening. Here, exogenous ethylene (ETH, 100 µL/L, 12 h) rapidly accelerated 'Hayward' kiwifruit (Actinidia deliciosa) softening and ethylene production and was enhanced by supplementing with continuous treatment with methyl jasmonate (MeJA, 100 µM/L, 12 h) (ETH+MeJA). ETH+MeJA enhanced ACC synthase (ACS) activities and 1-aminocyclopropane-1-carboxylic acid (ACC) accumulation but not ACC oxidase (ACO) activity. Increased transcripts of ACS genes AdACS1 and AdACS2, ACS activity, and ethylene production were positively correlated. The abundance of AdACS1 was about 6-fold higher than AdACS2. RNA-seq identified 6 transcription factors among the 87 differentially expressed unigenes induced by ETH+MeJA. Dual-luciferase and electrophoretic mobility shift assays (EMSA) indicated that AdNAC2/3 physically interacted with and trans-activated the AdACS1 promoter 2.2- and 3.5-fold, respectively. Collectively, our results indicate that MeJA accelerates ethylene production in kiwifruit induced by exogenous ethylene, via a preferential activation of AdACS1 and AdACS2.

EjMYB8 Transcriptionally Regulates Flesh Lignification in Loquat Fruit.

Transcriptional regulatory mechanisms underlying lignin metabolism have been widely studied in model plants and woody trees, but seldom in fruits such as loquat, which undergo lignification. Here, twelve EjMYB genes, designed as EjMYB3-14, were isolated based on RNA-seq. Gene expression indicated that EjMYB8 and EjMYB9 were significantly induced in fruit with higher lignin content resulting from storage at low temperature (0°C), while two treatments (low temperature conditioning, LTC; heat treatment, HT) both alleviated fruit lignification and inhibited EjMYB8 and EjMYB9 expression. Dual-luciferase assays indicated that EjMYB8, but not EjMYB9, could trans-activate promoters of lignin-related genes EjPAL1, Ej4CL1 and Ej4CL5. Yeast one-hybrid assay indicated that EjMYB8 physically bind to Ej4CL1 promoter. Furthermore, the putative functions of EjMYB8 were verified using transient over-expression in both N. tabacum and loquat leaves, which increased lignin content. Moreover, combination of EjMYB8 and previously isolated EjMYB1 generated strong trans-activation effects on the Ej4CL1 promoter, indicating that EjMYB8 is a novel regulator of loquat fruit lignification.

Inhibition of TRB3 Protects Photoreceptors against Endoplasmic Reticulum Stress-Induced Apoptosis after Experimental Retinal Detachment.

PURPOSE: To investigate the expression of tribbles homologue 3 (TRB3) and its regulation on endoplasmic reticulum stress (ERS)-induced photoreceptor apoptosis after retinal detachment (RD) using a rat model. METHODS: RD animal model was created in Wistar rats by subretinal injection of 1% sodium hyaluronate. At various time points after RD, expression of TRB3 was detected by quantitative real-time PCR and Western blotting. TRB3 protein distribution in retina was evaluated by immunohistochemistry. RNA interference was used to inhibit TRB3 expression and subretinal injection of lentivirus TRB3 shRNA (LV-TRB3-sh) was performed. The rats were then randomly divided into four groups: normal control group, RD group, vehicle + RD group and LV-TRB3-sh + RD group. The mRNA and protein level of TRB3 as well as Caspase-12 were detected. TdT-mediated fluorescein-16-dUTP nick-end labeling (TUNEL) assay was used to detect the apoptosis of retinal cells. Retinal outer nuclear layer (ONL) thickness was measured to assess retina damage in each group. RESULTS: TRB3 expression and TRB3-positive cell count were significantly increased after RD and peaked at day 3 after RD. The ratio of TUNEL-positive photoreceptors and expression of ERS-induced apoptosis marker Caspase-12 in LV-TRB3-sh + RD group were significantly reduced. The ONL thickness in LV-TRB3-sh + RD group was thicker than that both in RD group and vehicle + RD group. CONCLUSION: TRB3 expression is up-regulated in retinas after RD and knockdown of TRB3 protects photoreceptors against ERS-induced apoptosis. TRB3 may be a crucial molecule in photoreceptor apoptosis induced by ERS after RD.

Evaluation of visual functional and morphology change in young patients with idiopathic choroidal neovascularization.

BACKGROUND: Idiopathic choroidal neovascularization (ICNV) is an uncommon disorder affecting primarily individuals younger than the age of 50 years. In CNV patients, no apparent cause can be determined. This study aimed to evaluate the functional and morphological change of the retina with ICNV in young adults. METHODS: In this retrospective study, 32 eyes of 32 patients with subfoveal or juxta/extra foveal ICNV had been admitted into the Shanghai First People's Hospital from January 2009 to July 2010. The functional changes were evaluated using the best corrected visual acuity (BCVA) and the microperimetry in the macular area. The morphology changes were evaluated using optical coherence tomography (OCT), the color fundus photography and the fluorescein angiography. RESULTS: Seventeen patients with juxta/extra foveal and 15 subfoveal CNV were investigated. The mean logarithm of the minimum angle of resolution (LogMAR) BCVA was 0.39, the mean central retinal thickness (CRT) was 334 µm, and the mean sensitivity (MS) was 11.8 decibels (dB). In the subfoveal group, there was a strong correlation between CRT and BCVA (r = -0.675, F = 2.167, P < 0.01); as well as that between CRT and MS (r = -0.681, F = 22.91, P < 0.01). While in the juxta/extra foveal CNV group, the correlation of CRT and BCVA was not significant (r = -0.071, F = 1.018, P > 0.05); neither was the correlation of CRT and MS (r = -0.142, F = 36.54, P > 0.05). The microperimetry (MP-1) test revealed 17 (53%) patients with stable fixation, 9 (28%) with relatively unstable and 6 (19%) with unstable fixation. Fixation stability correlated positively with sensitivity in the central 2° diameter area (r = 0.380, F = 3.213, P < 0.05) and the duration of symptoms (r = 0.401, F = 7.933, P < 0.05). CONCLUSIONS: ICNV was associated with reduced total MS, unstable fixation and eccentric fixation. These findings emphasized functional change in ICNV is beyond the BCVA and regular morphology change, which provided additional information of functional evaluation in clinical practice.

Effect of alcohol on morphology and mesostructure control of anionic-surfactant-templated mesoporous silica (AMS).

In the synthesis of anionic-surfactant-templated mesoporous silica (AMS), the effects of alcohols have been investigated for the first time. Without the addition of extra alcohols, spherical mesoporous silica with radially oriented mesopores could be obtained through the anionic surfactant templating route. By using alcohols with different carbon chain length such as ethanol, n-butanol, hexanol and 1-octanol as the additives, different morphologies and mesostructures of mesoporous silica were obtained. It was found that both the types and concentrations of alcohols in the synthesis solution could tune the morphologies and mesostructures of the AMS, giving rise to the formation of hexagonal mesoporous discs and particles with novel multi-layered inner structure. In general alcohol with appropriate carbon chain length such as n-butanol and hexanol could act as the co-surfactant in the synthesis of mesoporous silica templated by anionic surfactant.