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Pepper originated in South America and was introduced to China in the 16th century. With high nutritional value, pepper has an important role in health care, beauty, food, medicine, violence and other industries. It becomes one of the most important vegetable crops in China. With the gradual increase of cultivation area pepper ranks the top among vegetable crops in China in this aspect. In the process of pepper production, it inevitably suffers from various diseases, causing great losses to production. It is the most economical and effective measure to control diseases through selecting disease-resistant varieties, although the chemical control methods and agricultural control measures can reduce the harm to a certain extent. With the development of molecular biology, the combination of molecular breeding and conventional breeding methods for disease resistance is a direction of future breakthroughs. In recent years, great progress has been made in the molecular breeding of pepper disease resistance, especially, the molecular mechanism of disease resistance. Molecular breeding mainly includes two parts: one is marker-assisted breeding, and the other is creating disease-resistant breeding materials by means of genetic engineering. In marker-assisted breeding, molecular markers must be found first. Molecular markers are divided into gene markers, markers obtained by linkage analysis in segregation populations, and markers gotten by association analysis through sequencing of a large number of materials. The premise of genetic engineering is to isolate and obtain disease resistance genes, and then introduce them into pepper breeding materials with good economic traits, or mutate negatively regulated genes through gene editing technology or gene silencing technology to improve disease resistance of plants. In this paper, molecular markers and marker-assisted selection, molecular mechanism of disease resistance and disease-resistant germplasm (resistance to virus, bacterial wilt and Phytophthora capsici) obtained by genetic engineering technology are comprehensively introduced, and the development trend and research focus in the future are prospected.

The organization of chromatin into self-interacting domains is universal among eukaryotic genomes. Here, the authors report a reference-grade pepper genome assembly and use this reference to help describe the relationship among 3D chromatin conformation, chromatin function, and gene expression.

Stereopsis is the ability of human beings to get the 3D perception on real scenarios. The conventional stereopsis measurement is based on subjective judgment for stereograms, leading to be easily affected by personal consciousness. To alleviate the issue, in this paper, the EEG signals evoked by dynamic random dot stereograms (DRDS) are collected for stereogram recognition, which can help the ophthalmologists diagnose strabismus patients even without real-time communication. To classify the collected Electroencephalography (EEG) signals, a novel multi-scale temporal self-attention and dynamical graph convolution hybrid network (MTS-DGCHN) is proposed, including multi-scale temporal self-attention module, dynamical graph convolution module and classification module. Firstly, the multi-scale temporal self-attention module is employed to learn time continuity information, where the temporal self-attention block is designed to highlight the global importance of each time segments in one EEG trial, and the multi-scale convolution block is developed to further extract advanced temporal features in multiple receptive fields. Meanwhile, the dynamical graph convolution module is utilized to capture spatial functional relationships between different EEG electrodes, in which the adjacency matrix of each GCN layer is adaptively tuned to explore the optimal intrinsic relationship. Finally, the temporal and spatial features are fed into the classification module to obtain prediction results. Extensive experiments are conducted on collected datasets i.e., SRDA and SRDB, and the results demonstrate the proposed MTS-DGCHN achieves outstanding classification performance compared with the other methods. The datasets are available at https://github.com/YANGeeg/TJU-SRD-datasets and the code is at https://github.com/YANGeeg/MTS-DGCHN.

The fruit development and ripening process involve a series of changes regulated by fine-tune gene expression at the transcriptional level. Acetylation levels of histones on lysine residues are dynamically regulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs), which play an essential role in the control of gene expression. However, their role in regulating fruit development and ripening process, especially in pepper (Capsicum annuum), a typical non-climacteric fruit, remains to understand. Herein, we performed genome-wide analyses of the HDAC and HAT family in the pepper, including phylogenetic analysis, gene structure, encoding protein conserved domain, and expression assays. A total of 30 HAT and 15 HDAC were identified from the pepper genome and the number of gene differentiation among species. The sequence and phylogenetic analysis of CaHDACs and CaHATs compared with other plant HDAC and HAT proteins revealed gene conserved and potential genus-specialized genes. Furthermore, fruit developmental trajectory expression profiles showed that CaHDAC and CaHAT genes were differentially expressed, suggesting that some are functionally divergent. The integrative analysis allowed us to propose CaHDAC and CaHAT candidates to be regulating fruit development and ripening-related phytohormone metabolism and signaling, which also accompanied capsaicinoid and carotenoid biosynthesis. This study provides new insights into the role of histone modification mediate development and ripening in non-climacteric fruits.

Abstract Background The basic helix–loop–helix (bHLH) transcription factors (TFs) serve crucial roles in regulating plant growth and development and typically participate in biological processes by interacting with other TFs. Capsorubin and capsaicinoids are found only in Capsicum, which has high nutritional and economic value. However, whether bHLH family genes regulate capsorubin and capsaicinoid biosynthesis and participate in these processes by interacting with other TFs remains unknown. Results In this study, a total of 107 CabHLHs were identified from the Capsicum annuum genome. Phylogenetic tree analysis revealed that these CabHLH proteins were classified into 15 groups by comparing the CabHLH proteins with Arabidopsis thaliana bHLH proteins. The analysis showed that the expression profiles of CabHLH009, CabHLH032, CabHLH048, CabHLH095 and CabHLH100 found in clusters C1, C2, and C3 were similar to the profile of carotenoid biosynthesis in pericarp, including zeaxanthin, lutein and capsorubin, whereas the expression profiles of CabHLH007, CabHLH009, CabHLH026 , CabHLH063 and CabHLH086 found in clusters L5, L6 and L9 were consistent with the profile of capsaicinoid accumulation in the placenta. Moreover, CabHLH007, CabHLH009, CabHLH026 and CabHLH086 also might be involved in temperature-mediated capsaicinoid biosynthesis. Yeast two-hybrid (Y2H) assays demonstrated that CabHLH007, CabHLH009, CabHLH026 , CabHLH063 and CabHLH086 could interact with MYB31, a master regulator of capsaicinoid biosynthesis. Conclusions The comprehensive and systematic analysis of CabHLH TFs provides useful information that contributes to further investigation of CabHLHs in carotenoid and capsaicinoid biosynthesis.

Abstract Background Pancreatic ductal adenocarcinoma (PDAC) is one of the most malignant diseases because of its non-symptomatic tumorigenesis. We previous found heat shock factor 1 (HSF1) was critical for PDAC progression and the aim of this study was to clarified the mechanisms on early activation of HSF1 and its role in the pancreatic cancer tumorigenesis. Methods The expression and location of HSF1 on human or mice pancreatic tissues were examined by immunohistochemically staining. We mainly used pancreatic acinar cell 3-dimensional (3D) culture and a spontaneous pancreatic precancerous lesion mouse model called LSL-Kras G12D/+ ; Pdx1-Cre (KC) (and pancreatitis models derived from KC mice) to explore the pro-tumorigenesis mechanisms of the HSF1 in vitro and in vivo. Bioinformatics and molecular experiments were used to explore the underlying mechanisms between HSF1 and epidermal growth factor receptor (EGFR). Results In this study, we found that pharmacological inhibition of HSF1 slowed pancreatic cancer initiation and suppressed the pancreatitis-induced formation of pancreatic precancerous lesion. Next, bioinformatics analysis revealed the closely linked between HSF1 and EGFR pathway and we also confirmed their parallel activation in pancreatic precancerous lesions. Besides, the pharmacological inhibition of EGFR suppressed the initiation of pancreatic cancer and the activation of HSF1 in vivo. Indeed, we demonstrated that the EGFR activation that mediated pancreatic cancer tumorigenesis was partly HSF1-dependent in vitro. Conclusion Hence, we concluded that the EGFR-HSF1 axis promoted the initiation of pancreatic cancer.

Abstract Background ERF transcription factors (TFs) belong to the Apetala2/Ethylene responsive Factor (AP2/ERF) TF family and play a vital role in plant growth and development processes. Capsorubin and capsaicinoids have relatively high economic and nutritional value, and they are specifically found in Capsicum. However, there is little understanding of how ERFs participate in the regulatory networks of capsorubin and capsaicinoids biosynthesis. Results In this study, a total of 142 ERFs were identified in the Capsicum annuum genome. Subsequent phylogenetic analysis allowed us to divide ERFs into DREB (dehydration responsive element binding proteins) and ERF subfamilies, and further classify them into 11 groups with several subgroups. Expression analysis of biosynthetic pathway genes and CaERFs facilitated the identification of candidate genes related to the regulation of capsorubin and capsaicinoids biosynthesis; the candidates were focused in cluster C9 and cluster C10, as well as cluster L3 and cluster L4, respectively. The expression patterns of CaERF82, CaERF97, CaERF66, CaERF107 and CaERF101, which were found in cluster C9 and cluster C10, were consistent with those of accumulating of carotenoids (β-carotene, zeaxanthin and capsorubin) in the pericarp. In cluster L3 and cluster L4, the expression patterns of CaERF102, CaERF53, CaERF111 and CaERF92 were similar to those of the accumulating capsaicinoids. Furthermore, CaERF92, CaERF102 and CaERF111 were found to be potentially involved in temperature-mediated capsaicinoids biosynthesis. Conclusion This study will provide an extremely useful foundation for the study of candidate ERFs in the regulation of carotenoids and capsaicinoids biosynthesis in peppers.

The eggplant (Solanum melongena L.) is rich in vitamin P (also known as rutin), which is beneficial for humans. In this study, the vitamin P contents of 53 eggplant lines were measured via UV spectrophotometry. The results showed that the vitamin P content differed significantly among the eggplant lines and the actual contents of vitamin P in fresh fruit pulp and fresh peel were 0.18–0.82 mg · g−1 and 0.42–2.32 mg · g−1, respectively. Furthermore, the mixed major gene and polygene inheritance model method was used for the inheritance analysis of the vitamin P content in F2 populations of three hybridization combinations. Inheritance analysis demonstrated that the vitamin P content of these eggplant lines was a quantitative trait. One or two major genes were the contributor, and the genetic effect was an additive-dominance effect. The high vitamin P content trait was regulated by the main gene and followed an additive effect. The heritability of the major genes controlling the high vitamin P content was low, while the heritability of the major gene that controls the low vitamin P content trait was high. These results provide a theoretical basis for the breeding of eggplants with high vitamin P content.

To improve the understanding of molecular mechanisms of anther and/or pollen development in Chili pepper, in the present study, full-length cDNA and DNA sequences of the pollen development-related gene CaMF5 were obtained from the anthers of a Capsicum annuum nuclear male-fertile line. Sequence analysis indicated that the full length of CaMF5 was 747 bp, containing a maximum opening reading frame of 447 bp. Amino acid sequence alignment and phylogenetic analysis revealed that CaMF5 shared approximately 37%–77% homology with a series of uncharacterized or hypothetical proteins and late embryogenesis abundant (LEA) proteins from other plants. However, no LEA structural domain was detected in CaMF5, which indicated that it might be a new type of LEA gene. CaMF5 was only expressed in flower buds at stages 7 and 8 and in open flowers of the male-fertile line, whereas it exhibited no expression in any examined organs of the male-sterile line. In addition, CaMF5 showed the highest transcript abundance in the anthers of the male-fertile line, with no expression being detected in any other examined organs, such as the sepals, petals, pistils, roots, stems, or leaves. Taken together, our results suggest that CaMF5 is an anther-specific gene that might encode a new type of LEA protein related to anther and/or pollen development in C. annuum. Keywords: Capsicum annuum, CaMF5, Anther-specific gene, Late embryogenesis abundant, Expression analysis

Progoitrin (2-hydroxy-3-butenyl glucosinolate, PRO) is the main source of bitterness of Brassica plants. Research on the biosynthesis of PRO glucosinolate can aid the understanding of the nutritional value in Brassica plants. In this study, four ODD genes likely involved in PRO biosynthesis were cloned from Chinese kale. These four genes, designated as BocODD1–4, shared 75–82% similarities with the ODD sequence of Arabidopsis. The sequences of these four BocODDs were analyzed, and BocODD1 and BocODD2 were chosen for further study. The gene BocODD1,2 showed the highest expression levels in the roots, followed by the leaves, flowers, and stems, which is in accordance with the trend of the PRO content in the same tissues. Both the expression levels of BocODD1,2 and the content of PRO were significantly induced by high- and low-temperature treatments. The function of BocODDs involved in PRO biosynthesis was identified. Compared with the wild type, the content of PRO was increased twofold in the over-expressing BocODD1 or BocODD2 plants. Meanwhile, the content of PRO was decreased in the BocODD1 or BocODD2 RNAi lines more than twofold compared to the wildtype plants. These results suggested that BocODD1 and BocODD2 may play important roles in the biosynthesis of PRO glucosinolate in Chinese kale.

Pancreatic stellate cells (PSCs), a key component of the tumor microenvironment, contribute to tumor invasion, metastasis, and chemoresistance. Osteopontin (OPN), a phosphorylated glycoprotein, is overexpressed in pancreatic cancer. However, OPN expression in PSCs and its potential roles in tumor–stroma interactions remain unclear. The present study first showed that OPN is highly expressed and secreted in activated PSCs driven by hypoxia, and this process is in a ROS‐dependent manner; in addition, OPN was shown to be involved in the PSC‐induced epithelial–mesenchymal transition (EMT) and cancer stem cell (CSC)‐like properties of pancreatic cancer cells (PCCs). Mechanistically, OPN from activated PSCs interacts with the transmembrane receptor integrin αvβ3 on PCCs to upregulate forkhead box protein M1 (FOXM1) expression and induce malignant phenotypes of PCCs. Moreover, the Akt and Erk pathways participate in OPN/integrin αvβ3 axis‐induced FOXM1 expression of PCCs. Our further analysis showed that OPN and FOXM1 are significantly upregulated in pancreatic cancer tissues and are associated with poor clinical outcome, indicating that OPN and FOXM1 might be considered as diagnostic and prognostic biomarkers for patients with pancreatic cancer. In conclusion, we show here for the first time that OPN promotes the EMT and CSC‐like properties of PCCs by activating the integrin αvβ3‐Akt/Erk‐FOXM1 cascade in a paracrine manner, suggesting that targeting the tumor microenvironment represents a promising therapeutic strategy in pancreatic cancer.

This paper focuses on designing a medium access control and channel usage algorithm in multi-rate wireless local area networks for improving the efficiency and fairly sharing channel resources among the contending nodes. Aiming for the problems that the high collision is often caused by binary exponential backoff mechanism in the legacy IEEE 802.11 and the shared channel can be overused by low bitrate nodes, we propose a differentiated reservation (DR) algorithm to reduce the collision among the contending nodes by setting their backoff counter as a deterministic value once accessing successfully to the channel. Furthermore, to eliminate the performance anomaly, some nodes are permitted to send multiple packets in one transmission opportunity according to their feature. Moreover, we present the implementation of the DR algorithm that is readily applied to both the existing 802.11 DCF and 802.11e EDCA networks with minimum modification. In addition, we also investigate the limitation of the DR algorithm and propose a group-based differentiated reservation (GDR) algorithm applied to high dense scenarios. The results of the theoretical analysis and simulation validate that our proposed algorithms (DR and GDR) can obtain high throughput, good airtime fairness, and low collision rate.

With the development of deep learning, image super-resolution has made great breakthroughs. However, compared with a color image, the performance of depth map super-resolution is still poor. To address this problem, multilevel recursive guidance and progressive supervised network (MRG-PS) is proposed in this paper. First, a multilevel recursive guidance architecture is presented to extract features of a color stream and depth stream, in which the depth stream is guided by the color features at each level. Second, a progressive supervision module is developed to supervise the multilevel recursion to obtain depth residual information on different levels. Finally, a residual fusion and construction strategy is designed to fuse all residual information and reconstruct the high-resolution depth map. The experimental results demonstrate that the proposed method outperforms the state-of-the-art methods.

Sketch-based image retrieval (SBIR) is a challenging task due to the cross-domain gap between sketch queries and natural images. In this paper, we propose a novel edge-guided cross-domain learning network to reduce the domain gap. In particular, edge maps extracted from natural images are introduced as the bridge between two domains, and the inputs from different domains are embedded into a common feature space. An edge guidance module is proposed to fuse natural images and the corresponding edge maps, which guides the network to generate more discriminative features in the domain alignment process. Meanwhile, a shape regression module is proposed to capture the inherent shape similarity between sketches and natural images. By training the proposed network in an end-to-end process, the sketch and natural image domains can be effectively associated, which potentially overcomes the challenge of the common feature learning for two heterogeneous domains. The experimental results on the SBIR dataset demonstrate that the proposed method achieves superior performance compared with the state-of-the-art methods.

Pancreatic cancer is characterized by a hypoxic tumor microenvironment, which is primarily caused by massive fibrosis with pancreatic stellate cells (PSCs) as a main component. Our previous studies have shown that resveratrol can significantly inhibit pancreatic cancer. However, whether resveratrol can inhibit hypoxia-induced cancer development remains unclear. The objective of this study was to explore whether PSCs and hypoxia synergistically mediate aggressiveness in pancreatic cancer and detect the potential pleiotropic protective effects of resveratrol on hypoxia-induced pancreatic cancer progression. Human PSCs were treated with vehicle or resveratrol under normoxic or hypoxic conditions (3% O 2 ), and PSC activation was assessed by immunofluorescence staining. SiRNA was used to silence hypoxia-inducible factor 1 (HIF-1) expression. The invasive capacity of Panc-1 and Mia Paca-2 cells cocultured with conditioned medium from PSCs was assessed by Transwell assays. To examine tumor formation kinetics, KPC (LSL-Kras G12D/+ , Trp53 fl/+ , and Pdx1-Cre) mice were sacrificed at different time points. To investigate the antitumor effects of resveratrol in vivo, 8-wk-old KPC mice were divided into two groups and treated daily with or without 50 mg/kg resveratrol. Our data indicate that hypoxia induces PSC activation via HIF-1 and that the interleukin 6, vascular endothelial growth factor A, and stromal cell-derived factor 1 derived from activated PSCs promote both invasion and the epithelial–mesenchymal transition and inhibit apoptosis in pancreatic cancer cells. However, resveratrol inhibits hypoxia-induced PSC activation, blocks the interplay between PSCs and pancreatic cancer cells, and suppresses the malignant progression of pancreatic cancer and stromal desmoplasia in a KPC mouse model. Our data highlight that activated PSCs and intratumoral hypoxia are essential targets for novel strategies to prevent tumor–microenvironment interactions. Furthermore, the polyphenolic compound resveratrol effectively ameliorates the malignant progression of pancreatic ductal adenocarcinoma.

Abstract Background Hippo/YAP pathway is known to be important for development, growth and organogenesis, and dysregulation of this pathway leads to tumor progression. We and others find that YAP is up-regulated in pancreatic ductal adenocarcinoma (PDAC) and associated with worse prognosis of patients. Activated pancreatic stellate cells (PSCs) forming the components of microenvironment that enhance pancreatic cancer cells (PCs) invasiveness and malignance. However, the role and mechanism of YAP in PDAC tumor-stromal interaction is largely unknown. Methods The expression of YAP in Pancreatic cancer cell lines and PDAC samples was examined by Western blot and IHC. The biological role of YAP on cancer cell proliferation, epithelial-mesenchymal transition (EMT) and invasion were evaluated by MTT, Quantitative real-time PCR analysis, Western blot analysis and invasion assay. The effect of YAP on PSC activation was evaluated by PC-PSC co-culture conditions and xenograft PDAC mouse model. Results Firstly, knockdown of YAP inhibits PDAC cell proliferation and invasion in vitro. In addition, YAP modulates the PC and PSC interaction via reducing the production of connective tissue growth factor (CTGF) from PCs, inhibits paracrine-mediated PSC activation under PC-PSC co-culture conditions and in turn disrupts TGF-β1-mediated tumor-stromal interactions. Lastly, inhibiting YAP expression prevents tumor growth and suppresses desmoplastic reaction in vivo. Conclusions These results demonstrate that YAP contributes to the proliferation and invasion of PC and the activation of PSC via tumor-stromal interactions and that targeting YAP may be a promising therapeutic strategy for PDAC treatment.

Abstract Background Pancreatic cancer is a lethal disease in part because of its potential for aggressive invasion and metastasis. Lipoxin A4 (LXA4) is one of the metabolites that is derived from arachidonic acid and that is catalyzed by 15-lipoxygenase (15-LOX), and it has recently been reported to exhibit anti-cancer effects. However, the role of LXA4 in pancreatic cancer remains to be elucidated. Methods Pancreatic cell lines were treated with vehicle or LXA4, and the invasive capacity was then assessed by Transwell assays. The expression of epithelial and mesenchymal markers was determined by western blotting and immunofluorescence. Anti-TGF-β1 neutralizing antibody and exogenous recombinant human TGF-β1 (rhTGF-β1) were used to study the effect of LXA4 on the TGF-β signaling. A liver metastasis model was applied to investigate the effect of LXA4 in vivo. The correlation between the Lipoxin effect score (LES) and the clinical-pathological features of pancreatic cancer was also analyzed. Results We found that in patients with pancreatic cancer, low LES was correlated with aggressive metastatic potential. The LXA4 activity, which was mediated by the LXA4 receptor FPRL1, could significantly suppress invasion capacity and mesenchymal phenotypes. The expression and autocrine signaling pathway activity of TGF-β1 were also downregulated by LXA4. In the liver metastasis model in nude mice, the stable analog of LXA4, BML-111, could inhibit the metastasis of pancreatic cancer cells. Conclusion Our results demonstrated that LXA4 could reverse mesenchymal phenotypes, which attenuated invasion and metastasis via the inhibition of autocrine TGF-β1 signaling in pancreatic cancer, which may provide a new strategy to prevent the metastasis of pancreatic cancer.

The 2-oxoglutarate and Fe(II)-dependent dioxygenase (2OGD) superfamily is the second largest enzyme family in the plant genome, and its members are involved in various oxygenation and hydroxylation reactions. Due to their important biochemical significance in metabolism, a systematic analysis of the plant 2OGD genes family is necessary. Here, we identified 160, 179, and 337 putative 2OGDs from Brassica rapa, Brassica oleracea, and Brassica napus. According to their gene structure, domain, phylogenetic features, function, and previous studies, we also divided 676 2OGDs into three subfamilies: DOXA, DOXB, and DOXC. Additionally, homologous and phylogenetic comparisons of three subfamily genes provided valuable insight into the evolutionary characteristics of the 2OGD genes from Brassica plants. Expression profiles derived from the transcriptome and Genevestigator database exhibited distinct expression patterns of the At2OGD, Br2OGD, and Bo2OGD genes in different developmental stages, tissues, or anatomical parts. Some 2OGD genes showed high expression levels in various tissues, such as callus, seed, silique, and root tissues, while other 2OGD genes were expressed at very low levels in other tissues. Analysis of six Bo2OGD genes in different tissues by qRT-PCR indicated that these genes are involved in the metabolism of gibberellin, which in turn regulates plant growth and development. Our working system analysed 2OGD gene families of three Brassica plants and laid the foundation for further study of their functional characterization.

Chinese kale is an important vegetable crop in China, especially in South China where the majority of varieties are grown. It originated in South China and spread throughout Southeast Asia thereafter. Chinese kale can be classified into two types according to whether the petals are white or yellow. There are also three main cultivated types based on the edible organs, including the stalk and leaf type, the stalk type, and the leaf type. Two primary types have also been defined based on stalk color, including green stalks and red stalks. They are also cultivated based on the type of stalk, including main stalk and lateral stalk types. Significant differences have also been observed in glucosinolate content among the varieties, and a 40-fold difference in neoindle-3-methyl glucosinolate was detected across the cultivars.

With the development of 3-D applications, such as 3-D reconstruction and object recognition, accurate and high-quality depth map is urgently required. Recently, depth cameras have been affordable and widely used in daily life. However, the captured depth map always owns low resolution and poor quality, which limits its practical application. This paper proposes a color-guided depth map super resolution method using convolutional neural network. First, a dual-stream convolutional neural network, which integrates the color and depth information simultaneously, is proposed for depth map super resolution. Then, the optimized edge map generated by the high resolution color image and low resolution depth map is used as additional information to refine the object boundary in the depth map. Experimental results demonstrate the effectiveness of the proposed method compared with the state-of-the-art methods.

Glucoraphanin is a plant secondary metabolite that is involved in plant defense and imparts health-promoting properties to cruciferous vegetables. In this study, three genes involved in glucoraphanin metabolism, branched-chain aminotransferase 4 (BCAT4), methylthioalkylmalate synthase 1 (MAM1) and dihomomethionine N-hydroxylase (CYP79F1), were cloned from Chinese kale (Brassica oleracea var. alboglabra Bailey). Sequence homology and phylogenetic analysis identified these genes and confirmed the evolutionary status of Chinese kale. The transcript levels of BCAT4, MAM1 and CYP79F1 were higher in cotyledon, leaf and stem compared with flower and silique. BCAT4, MAM1 and CYP79F1 were expressed throughout leaf development with lower transcript levels during the younger stages. Glucoraphanin content varied extensively among different varieties, which ranged from 0.25 to 2.73 µmol·g−1 DW (dry weight). Expression levels of BCAT4 and MAM1 were high at vegetative–reproductive transition phase, while CYP79F1 was expressed high at reproductive phase. BCAT4, MAM1 and CYP79F1 were expressed significantly high in genotypes with high glucoraphanin content. All the results provided a better understanding of the roles of BCAT4, MAM1 and CYP79F1 in the glucoraphanin biosynthesis of Chinese kale.

Legacy IEEE 802.11 Medium Access Control (MAC) adopts the Distributed Coordination Function (DCF) mechanism, which provides the same access opportunity for all contenders. However, in dense multi-rate Wireless Local Area Networks (WLANs), the pure distributed control mechanism will cause high collision rate and performance anomaly, which results in low network utilization and wasting valuable channel resources. In this paper, we present a decoupling MAC mechanism (DMAC) based on the idea of contention/reservation to reduce collision and realize collision free data transmission. In proposed mechanism, the channel access time is partitioned into channel contention process and data transmission process. The proposed algorithm makes full use of the distributed random channel access mechanism and performs a centralized collision-free data transmission. Wherein, we also design an adaptive algorithm to adjust the length of the contention period to improve the channel utilization. Furthermore, we further propose two airtime fairness algorithms Improve-DMAC1 (I-DMAC1) and Improve-DMAC2 (I-DMAC2) for delay sensitive network and high throughput network scenarios, respectively, to solve the performance anomaly in multi-rate WLANs, based on DMAC. We verify the effectiveness of these decoupling algorithms through extensive simulations. Moreover, the simulation results show that the proposed algorithms achieve better performance than the 802.11 standard and other protocols.

Chinese kale (Brassica oleracea var. chinensis Lei) is an important vegetable crop in South China, valued for its nutritional content and taste. Nonetheless, the thermal tolerance of Chinese kale still needs improvement. Molecular characterization of Chinese kale’s heat stress response could provide a timely solution for developing a thermally tolerant Chinese kale variety. Here, we report the cloning of multi-protein bridging factor (MBF) 1c from Chinese kale (BocMBF1c), an ortholog to the key heat stress responsive gene MBF1c. Phylogenetic analysis showed that BocMBF1c is highly similar to the stress-response transcriptional coactivator MBF1c from Arabidopsis thaliana (AtMBF1c), and the BocMBF1c coding region conserves MBF1 and helix-turn-helix (HTH) domains. Moreover, the promoter region of BocMBF1c contains three heat shock elements (HSEs) and, thus, is highly responsive to heat treatment. This was verified in Nicotiana benthamiana leaf tissue using a green fluorescent protein (GFP) reporter. In addition, the expression of BocMBF1c can be induced by various abiotic stresses in Chinese kale which indicates the involvement of stress responses. The BocMBF1c-eGFP (enhanced green fluorescent protein) chimeric protein quickly translocated into the nucleus under high temperature treatment in Nicotiana benthamiana leaf tissue. Overexpression of BocMBF1c in Arabidopsis thaliana results in a larger size and enhanced thermal tolerance compared with the wild type. Our results provide valuable insight for the role of BocMBF1c during heat stress in Chinese kale.

High temperature (HT) stress affects the growth and production of cucumbers, but genetic resources with high heat tolerance are very scarce in this crop. Calmodulin (CaM) has been confirmed to be related to the regulation of HT stress resistance in plants. CsCaM3, a CaM gene, was isolated from cucumber inbred line “02-8.” Its expression was characterized in the present study. CsCaM3 transcripts differed among the organs and tissues of cucumber plants and could be induced by HTs or abscisic acid, but not by salicylic acid. CsCaM3 transcripts exhibited subcellular localization to the cytoplasm and nuclei of cells. Overexpression of CsCaM3 in cucumber plants has the potential to improve their heat tolerance and protect against oxidative damage and photosynthesis system damage by regulating the expression of HT-responsive genes in plants, including chlorophyll catabolism-related genes under HT stress. Taken together, our results provide useful insights into stress tolerance in cucumber.

Glucosinolates are Brassicaceae-specific secondary metabolites that act as crop protectants, flavor precursors, and cancer-prevention agents, which shows strong evidences of anticarcinogentic, antioxidant, and antimicrobial activities. MYB28, the R2R3-MYB28 transcription factor, directly activates genes involved in aliphatic glucosinolate biosynthesis. In this study, the MYB28 homology (BoaMYB28) was identified in Chinese kale (Brassica oleracea var. alboglabra Bailey). Analysis of the nucleotide sequence indicated that the cDNA of BoaMYB28 was 1257 bp with an ORF of 1020 bp. The deduced BoaMYB28 protein was a polypeptide of 339 amino acid with a putative molecular mass of 38 kDa and a pI of 6.87. Sequence homology and phylogenetic analysis showed that BoaMYB28 was most closely related to MYB28 homologs from the Brassicaceae family. The expression levels of BoaMYB28 varies across the tissues and developmental stages. BoaMYB28 transcript levels were higher in leaves and stems compared with those in cotyledons, flowers, and siliques. BoaMYB28 was expressed across all developmental leaf stages, with higher transcript accumulation in mature and inflorescence leaves. Over-expression and RNAi studies showed that BoaMYB28 retains the basic MYB28 gene function as a major transcriptional regulator of aliphatic glucosinolate pathway. The results indicated that over-expression and RNAi lines showed no visible difference on plant morphology. The contents of aliphatic glucosinolates and transcript levels of aliphatic glucosinolate biosynthesis genes increased in over-expression lines and decreased in RNAi lines. In over-expression lines, aliphatic glucosinolate contents were 1.5- to 3-fold higher than those in the wild-type, while expression levels of aliphatic glucosinolate biosynthesis genes were 1.5- to 4-fold higher than those in the wild-type. In contrast, the contents of aliphatic glucosinolates and transcript levels of aliphatic glucosinolate biosynthesis genes in RNAi lines were considerably lower than those in the wild-type. The results suggest that BoaMYB28 has the potential to alter the aliphatic glucosinolates contents in Chinese kale at the genetic level.

Chinese kale is a native vegetable in Southern China and the flowering stalk is the most commonly used edible part due to its high glucosinolate content and other nutritional qualities. The GTR protein played important roles in the glucosinolate transport process. In this study, three BocGTR1 genes were cloned from Chinese kale for the first time. Their gene structure, physicochemical properties, signal peptides, transmembrane structures, functional domains, second and third-order protein structures, and phylogenetic relationships were predicted. The expression levels of BocGTR1a and BocGTR1c were much higher than those of BocGTR1b in various tissues, especially in leaves and buds. In addition, the expression patterns of three genes were examined under various abiotic stresses or hormone treatment, including those induced by wounding, heat stress, methyl jasmonate, salicylic acid, salt, and MgCl2 treatment. BocGTR1a and BocGTR1c were strongly induced by wounding and heat stress. The expression of BocGTR1a and BocGTR1c was significantly silenced in plants transformed by RNAi technology. Total glucosinolate content was significantly decreased in mature leaves and increased in roots of RNAi-transformed plants compared to wild-type plants. In addition, we found that BocGTR1a and BocGTR1c may participate in glucosinolate accumulation in different tissues with a selection for specific glucosinolates. These results indicated that BocGTR1a and BocGTR1c may be the key genes involved in the glucosinolate accumulation in different tissues of Chinese kale.

Plants are constantly challenged by environmental stresses, including drought and high salinity. Improvement of drought and osmotic stress tolerance without yield decrease has been a great challenge in crop improvement. The Arabidopsis ENHANCED DROUGHT TOLERANCE1/HOMEODOMAIN GLABROUS11 (AtEDT1/HDG11), a protein of the class IV HD-Zip family, has been demonstrated to significantly improve drought tolerance in Arabidopsis, rice and pepper. Here, we report that AtEDT1/HDG11 confers drought and osmotic stress tolerance in the Chinese kale. AtEDT1/HDG11-overexpression lines exhibit auxin-overproduction phenotypes, such as long hypocotyls, tall stems, more root hairs and a larger root system architecture. Compared with the untransformed control, transgenic lines have significantly reduced stomatal density. In the leaves of transgenic Chinese kale plants, proline (Pro) content and reactive oxygen species-scavenging enzyme activity was significantly increased after drought and osmotic stress, particularly compared to wild kale. More importantly, AtEDT1/HDG11-overexpression leads to abscisic acid (ABA) hypersensitivity, resulting in ABA inhibitor germination and induced stomatal closure. Consistent with observed phenotypes, the expression levels of auxin, ABA and stress-related genes were also altered under both normal and/or stress conditions. Further analysis showed that AtEDT1/HDG11, as a transcription factor, can target the auxin biosynthesis gene YUCC6 and ABA response genes ABI3 and ABI5. Collectively, our results provide a new insight into the role of AtEDT1/HDG11 in enhancing abiotic stress resistance through auxin- and ABA- mediated signaling response in Chinese kale.

Previous work on gene expression analysis based on RNA sequencing identified a variety of differentially expressed cDNA fragments in the genic male sterile-fertile line 114AB of Capsicum annuum L. In this work, we examined the accumulation of one of the transcript-derived fragments (TDFs), CaMF3 (male fertile 3), in the flower buds of a fertile line. The full genomic DNA sequence of CaMF3 was 1,951 bp long and contained 6 exons and 5 introns, with the complete sequence encoding a putative 25.89 kDa protein of 234 amino acids. The predicted protein of CaMF3 shared sequence similarity with members of the isoamyl acetate-hydrolyzing esterase (IAH1) protein family. CaMF3 expression was detected only in flower buds at stages 7 and 8 and in open flowers of a male fertile line; no expression was observed in any organs of a male sterile line. Fine expression analysis revealed that CaMF3 was expressed specifically in anthers of the fertile line. These results suggest that CaMF3 is an anther-specific gene that may be essential for anther or pollen development in C. annuum.

Regarding access point (AP) overload and performance anomaly which is caused by mobile terminals with different bitrates, a joint AP association and bandwidth allocation optimization algorithm is presented in this paper. Meanwhile, load balancing and proportional fairness are analyzed and formulated as an optimization model. Then, we present a Fair Bandwidth Allocation algorithm based on clients’ Business Priority (FBA-BP), which allocates bandwidth based on the bandwidth demand of clients and their business priority. Furthermore, we propose a Categorized AP Association algorithm based on clients’ demands (CAA-BD), which classifies APs by different types of clients and chooses an optimal associating AP for a new client according to AP categories and the aggregated demand transmission time that are calculated by the FBA-BP algorithm. The CAA-BD can achieve load balance and solve the performance anomaly caused by multi-rate clients coexisting. The simulation results show that our proposed algorithm obtains significant performance in terms of AP utilization, throughput, transmission delay and channel fairness in different client density levels compared with the categorized and Strong Signal First (SSF) algorithms.

This study was designed to control plant fertility by cell lethal gene Barnase expressing at specific developmental stage and in specific tissue of male organ under the control of Cre/loxP system, for heterosis breeding, producing hybrid seed of eggplant. The Barnase-coding region was flanked by loxP recognition sites for Cre-recombinase. The eggplant inbred/pure line ('E-38') was transformed with Cre gene and the inbred/pure line ('E-8') was transformed with the Barnase gene situated between loxp. The experiments were done separately, by means of Agrobacterium co-culture. Four T0-plants with the Barnase gene were obtained, all proved to be male-sterile and incapable of producing viable pollen. Flowers stamens were shorter, but the vegetative phenotype was similar to wild-type. Five T0-plants with the Cre gene developed well, blossomed out and set fruit normally. The crossing of male-sterile Barnase-plants with Cre expression transgenic eggplants resulted in site-specific excision with the male-sterile plants producing normal fruits. With the Barnase was excised, pollen fertility was fully restored in the hybrids. The phenotype of these restored plants was the same as that of the wild-type. Thus, the Barnase and Cre genes were capable of stable inheritance and expression in progenies of transgenic plants.

The capsaicinoids are a group of compounds produced by chili pepper fruits and are used widely in many fields, especially in medical purposes. The capsaicinoid biosynthetic pathway has not yet been established clearly. To understand more knowledge in biosynthesis of capsaicinoids, we applied RNA-seq for the mixture of placenta and pericarp of pungent pepper (Capsicum frutescens L.). We have assessed the effect of various assembly parameters using different assembly software, and obtained one of the best strategies for de novo assembly of transcriptome data. We obtained a total 54,045 high-quality unigenes (transcripts) using Trinity software. About 92.65% of unigenes showed similarity to the public protein sequences, genome of potato and tomato and pepper (C. annuum) ESTs databases. Our results predicted 3 new structural genes (DHAD, TD, PAT), which filled gaps of the capsaicinoid biosynthetic pathway predicted by Mazourek, and revealed new candidate genes involved in capsaicinoid biosynthesis based on KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis. A significant number of SSR (Simple Sequence Repeat) and SNP (Single Nucleotide Polymorphism) markers were predicted in C. frutescens and C. annuum sequences, which will be helpful in the identification of polymorphisms within chili pepper populations. These data will provide new insights to the pathway of capsaicinoid biosynthesis and subsequent research of chili peppers. In addition, our strategy of de novo transcriptome assembly is applicable to a wide range of similar studies.