An R-R-type MYB transcription factor promotes non-climacteric pepper fruit carotenoid pigment biosynthesis.

Carotenoids are major accessory pigments in the chloroplast, and they also act as phytohormones and volatile compound precursors to influence plant development and confer characteristic colours, affecting both the aesthetic and nutritional value of fruits. Carotenoid pigmentation in ripening fruits is highly dependent on developmental trajectories. Transcription factors incorporate developmental and phytohormone signalling to regulate the biosynthesis process. By contrast to the well-established pathways regulating ripening-related carotenoid biosynthesis in climacteric fruit, carotenoid regulation in non-climacteric fruit is poorly understood. Capsanthin is the primary carotenoid of non-climacteric pepper (Capsicum) fruit; its biosynthesis is tightly associated with fruit ripening, and it confers red pigmentation to the ripening fruit. In the present study, using a coexpression analysis, we identified an R-R-type MYB transcription factor, DIVARICATA1, and demonstrated its role in capsanthin biosynthesis. DIVARICATA1 encodes a nucleus-localised protein that functions primarily as a transcriptional activator. Functional analyses showed that DIVARICATA1 positively regulates carotenoid biosynthetic gene (CBG) transcript levels and capsanthin levels by directly binding to and activating CBG promoter transcription. Furthermore, an association analysis revealed a significant positive association between DIVARICATA1 transcription level and capsanthin content. ABA promotes capsanthin biosynthesis in a DIVARICATA1-dependent manner. Comparative transcriptomic analysis of DIVARICATA1 in Solanaceae plants showed that its function likely differs among species. Moreover, the pepper DIVARICATA1 gene could be regulated by the ripening regulator MADS-RIN. The present study illustrates the transcriptional regulation of capsanthin biosynthesis and offers a target for breeding peppers with high red colour intensity.

Identification and characterization analysis of candidate genes controlling mushroom leaf development in Chinese kale by BSA-seq.

Mushroom leaves (MLs) are malformed leaves that develop from the leaf veins in some of Chinese kale genotypes. To study the genetic model and molecular mechanism of ML development in Chinese kale, the F2 segregation population was constructed by two inbred lines, genotype Boc52 with ML and genotype Boc55 with normal leaves (NL). In the present study, we have identified for the first time that the development of mushroom leaves may be affected by the change of adaxial-abaxial polarity of leaves. Examination of the phenotypes of F1 and F2 segregation populations suggested that ML development is controlled by two dominant major genes inherited independently. BSA-seq analysis showed that a major quantitative trait locus (QTL) qML4.1 that controls ML development is located within 7.4 Mb on chromosome kC4. The candidate region was further narrowed to 255 kb by linkage analysis combined with insertion/deletion (InDel) markers, and 37 genes were predicted in this region. According to the expression and annotation analysis, a B3 domain-containing transcription factor NGA1-like gene, BocNGA1, was identified as a key candidate gene for controlling ML development in Chinese kale. Fifteen single nucleotide polymorphisms (SNPs) were found in coding sequences and 21 SNPs and 3 InDels found in the promoter sequences of BocNGA1 from the genotype Boc52 with ML. The expression levels of BocNGA1 in ML genotypes are significantly lower than in the NL genotypes, which suggests that BocNGA1 may act as a negative regulator for ML genesis in Chinese kale. This study provides a new foundation for Chinese kale breeding and for the study of the molecular mechanism of plant leaf differentiation. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-023-01364-6.

Yap-Myc signaling induces pancreatic stellate cell activation through regulating glutaminolysis.

The accumulation of activated myofibroblastic pancreatic stellate cells (MF-PSCs) induces pancreatic cancer desmoplasia. These MF-PSCs are derived from quiescent pancreatic stellate cells (Q-PSCs). MF-PSCs in pancreatic cancer tend to glycolysis. However, increased glycolysis alone could not be sufficient for the increased metabolic demands of MF-PSCs. Yap and Myc signaling activation is involved in pancreatic cancer metabolism. Since elucidating the metabolic processes of MF-PSCs may be a promising strategy to suppress pancreatic cancer desmoplasia, we explored whether glutaminolysis meets the bioenergetic and biosynthetic demands of Q-PSCs converted into MF-PSCs and whether this is mediated by Yap signaling to Myc. In this study, we found that during the transdifferentiation of Q-PSCs into MF-PSCs, glutaminolysis regulatory genes were upregulated, and suppression of glutaminolysis inhibited transdifferentiation. Disrupting glutaminolysis in MF-PSCs inhibited cell growth, mitochondrial respiration, and fibrogenesis, while treatment of MF-PSCs with DKG (a glutaminolysis metabolite) reversed these activities. The expression of glutaminase (GLS1), a rate-limiting enzyme in glutaminolysis, was upregulated by Yap overexpression. Yap upregulates Myc to regulate the expression of GLS1 in MF-PSCs. Yap and Myc inhibitors disrupted glutaminolysis and inhibited myofibroblastic activities in PSCs. Thus, Yap-Myc signaling controls glutaminolysis to activate PSCs and might be a therapeutic target for pancreatic cancer desmoplasia.

Cytotoxic nortriterpenoids from the barks of Juglans cathayensis.

A chemical study of 90% ethanol extract of the barks of Juglans cathayensis resulted in the isolation of three new nortriterpenoids, jugcathenoids A-C (1-3). The structures of the new compounds were elucidated by spectroscopic analysis (NMR, IR, UV, and MS). The isolated nortriterpenoids were tested in vitro for cytotoxic activities against 6 pancreatic cell lines. As a result, compounds 1-3 exhibited some cytotoxic activities against all the tested tumor cell lines with IC50 values less than 50 µM.

A yes-associated protein 1- Notch1 receptor positive feedback loop promotes breast cancer lung metastasis by attenuating the bone morphogenetic protein 4-SMAD family member 1/5 signaling.

The Notch1 (Notch1 receptor) and yes-associated protein 1 (YAP1) signaling can regulate breast cancer metastasis. This study aimed at investigating whether and how these two signal pathways crosstalk to promote breast cancer lung metastasis. Here, we show that YAP1 expression was positively correlated with Notch1 in breast cancer according to bioinformatics and experimental validation. Mechanistically, YAP1 with TEA domain transcription factors (TEADs) enhanced Jagged1(JAG1)-Notch1 signaling. Meanwhile, Notch1 promoted YAP1 stability in breast cancer cells by inhibiting the ß-TrCP-mediated degradation, thereby, forming a YAP1- JAG1/Notch1 positive feedback loop in breast cancer. Furthermore, YAP1 enhanced the mammosphere formation and stemness of MDA-MB-231 cells by attenuating the inhibition of the BMP4-SMAD1/5 signaling. In vivo, the YAP1- JAG1/Notch1 positive feedback loop promoted the lung colonization of MDA-MB-231 cells. Our data for the first time indicate that the YAP1-Notch1 positive feedback loop promotes lung metastasis of breast cancer by modulating self-renewal and inhibiting the BMP4-SMAD1/5 signaling.

BocODD1 and BocODD2 Regulate the Biosynthesis of Progoitrin Glucosinolate in Chinese Kale.

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.

Genome-wide identification of the Capsicum bHLH transcription factor family: discovery of a candidate regulator involved in the regulation of species-specific bioactive metabolites.

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.

Dihydromyricetin Imbues Antiadipogenic Effects on 3T3-L1 Cells via Direct Interactions with 78-kDa Glucose-Regulated Protein.

BACKGROUND: Obesity is among the most serious public health problems worldwide, with few safe pharmaceutical interventions. Natural products have become an important source of potential anti-obesity therapeutics. Dihydromyricetin (DHM) exerts antidiabetic effects. The biochemical target of DHM, however, has been unknown. It is crucial to identify the biochemical target of DHM for elucidating its physiological function and therapeutic value. OBJECTIVES: The objective of this study was to identify the biochemical target of DHM. METHODS: An abundant antiadipogenic flavanonol was extracted from the herbal plant Ampelopsis grossedentata through bioassay-guided fractionation and characterized with high-resolution LC-MS and 1H and 13C nuclear magnetic resonance. Antiadipogenic experiments were done with mouse 3T3-L1 preadipocytes. A biochemical target of the chemical of interest was identified with drug affinity responsive target stability assay. Direct interactions between the chemical of interest and the protein target in vitro were predicted with molecular docking and subsequently confirmed with surface plasmon resonance. Expression levels of peroxisome proliferator-activated receptor γ (PPARγ), which is associated with 78-kDa glucose-regulated protein (GRP78), were measured with real-time qPCR. RESULTS: DHM was isolated, purified, and structurally characterized. Cellular studies showed that DHM notably reduced intracellular oil droplet formation in 3T3-L1 cells with a median effective concentration of 294 µM (i.e., 94 µg/mL). DHM targeted the ATP binding site of GRP78, which is associated with adipogenesis. An equilibrium dissociation constant between DHM and GRP78 was 21.8 µM. In 3T3-L1 cells upon treatment with DHM at 50 µM (i.e., 16 µg/mL), the expression level of PPARγ was downregulated to 53.9% of the solvent vehicle control's level. CONCLUSIONS: DHM targets GRP78 in vitro. DHM is able to reduce lipid droplet formation in 3T3-L1 cells through a mode of action that is plausibly associated with direct interactions between GRP78 and DHM, which is a step forward in determining potential applications of DHM as an anti-obesity agent.

Metformin suppresses HIF-1α expression in cancer-associated fibroblasts to prevent tumor-stromal cross talk in breast cancer.

The tumor microenvironment (TME) is a crucial factor in cancer progression. In breast cancer, cancer-associated fibroblasts (CAFs) and the derived stromal components have been recognized as comprising the majority of the pathological structure of the TME. In this study, we show that metformin (Met), a diabetes drug, transforms CAFs in the TME. Met disrupts tumor-stromal cross talk by preventing breast cancer cell transforming growth factor-ß (TGF-ß) signaling and the production of stromal-derived factor-1 (SDF-1) and interleukin-8 (IL-8) by CAFs. The suppression of bidirectional signaling between tumor cells and CAFs by Met is attributed to increased phospho-AMP kinase (p-AMPK) levels. By upregulating p-AMPK in CAFs, Met induces prolyl hydroxylases (PHDs), leading to the degradation of hypoxia-inducible factor-1α (HIF-1α) in CAFs. Moreover, interruption of HIF-1α-driven SDF-1 signaling in CAFs by Met leads to decreased breast cancer cell invasion. These findings suggest that Met may be used to target tumor-promoting signaling between CAFs and breast cancer cells in the TME.

Positive feedback in Cav-1-ROS signalling in PSCs mediates metabolic coupling between PSCs and tumour cells.

Caveolin-1 (Cav-1) is the principal structural component of caveolae, and its dysregulation occurs in cancer. However, the role of Cav-1 in pancreatic cancer (PDAC) tumorigenesis and metabolism is largely unknown. In this study, we aimed to investigate the effect of pancreatic stellate cell (PSC) Cav-1 on PDAC metabolism and aggression. We found that Cav-1 is expressed at low levels in PDAC stroma and that the loss of stromal Cav-1 is associated with poor survival. In PSCs, knockdown of Cav-1 promoted the production of reactive oxygen species (ROS), while ROS production further reduced the expression of Cav-1. Positive feedback occurs in Cav-1-ROS signalling in PSCs, which promotes PDAC growth and induces stroma-tumour metabolic coupling in PDAC. In PSCs, positive feedback in Cav-1-ROS signalling induced a shift in energy metabolism to glycolysis, with up-regulated expression of glycolytic enzymes (hexokinase 2 (HK-2), 6-phosphofructokinase (PFKP) and pyruvate kinase isozyme type M2 (PKM2)) and transporter (Glut1) expression and down-regulated expression of oxidative phosphorylation (OXPHOS) enzymes (translocase of outer mitochondrial membrane 20 (TOMM20) and NAD(P)H dehydrogenase [quinone] 1 (NQO1)). These events resulted in high levels of glycolysis products such as lactate, which was secreted by up-regulated monocarboxylate transporter 4 (MCT4) in PSCs. Simultaneously, PDAC cells took up these glycolysis products (lactate) through up-regulated MCT1 to undergo OXPHOS, with down-regulated expression of glycolytic enzymes (HK-2, PFKP and PKM2) and up-regulated expression of OXPHOS enzymes (TOMM20 and NQO1). Interrupting the metabolic coupling between the stroma and tumour cells may be an effective method for tumour therapy.

Systematic analysis of the Capsicum ERF transcription factor family: identification of regulatory factors involved in the regulation of species-specific metabolites.

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 (ß-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.

Natural variations in the MYB transcription factor MYB31 determine the evolution of extremely pungent peppers.

Plants produce countless specialized metabolites crucial for their development and fitness, and many are useful bioactive compounds. Capsaicinoids are intriguing genus-specialized metabolites that confer a pungent flavor to Capsicum fruits, and they are widely applied in different areas. Among the five domesticated Capsicum species, Capsicum chinense has a high content of capsaicinoids, which results in an extremely hot flavor. However, the species-specific upregulation of capsaicinoid-biosynthetic genes (CBGs) and the evolution of extremely pungent peppers are not well understood. We conducted genetic and functional analyses demonstrating that the quantitative trait locus Capsaicinoid1 (Cap1), which is identical to Pun3 contributes to the level of pungency. The Cap1/Pun3 locus encodes the Solanaceae-specific MYB transcription factor MYB31. Capsicum species have evolved placenta-specific expression of MYB31, which directly activates expression of CBGs and results in genus-specialized metabolite production. The capsaicinoid content depends on MYB31 expression. Natural variations in the MYB31 promoter increase MYB31 expression in C. chinense via the binding of the placenta-specific expression of transcriptional activator WRKY9 and augmentation of CBG expression, which promotes capsaicinoid biosynthesis. Our findings provide insights into the evolution of extremely pungent C. chinense, which is due to natural variations in the master regulator, and offers targets for engineering or selecting flavor in Capsicum.

The eggplant transcription factor MYB44 enhances resistance to bacterial wilt by activating the expression of spermidine synthase.

Bacterial wilt (BW) caused by Ralstonia solanacearum is a serious disease affecting the production of Solanaceae species, including eggplant (Solanum melongena). However, few resistance genes have been identified in eggplant, and therefore the underlying mechanism of BW resistance remains unclear. Hence, we investigated a spermidine synthase (SPDS) gene from eggplant and created knock-down lines with virus-induced gene silencing. After eggplant was infected with R. solanacearum, the SmSPDS gene was induced, concurrent with increased spermidine (Spd) content, especially in the resistant line. We speculated that Spd plays a significant role in the defense response of eggplant to BW. Moreover, using the yeast one-hybrid approach and dual luciferase-based transactivation assay, an R2R3-MYB transcription factor, SmMYB44, was identified as directly binding to the SmSPDS promoter, activating its expression. Overexpression of SmMYB44 in eggplant induced the expression of SmSPDS and Spd content, increasing the resistance to BW. In contrast, the SmMYB44-RNAi transgenic plants showed more susceptibility to BW compared with the control plants. Our results provide insight into the SmMYB44-SmSPDS-Spd module involved in the regulation of resistance to R. solanacearum. This research also provides candidates to enhance resistance to BW in eggplant.

Paracrine HGF/c-MET enhances the stem cell-like potential and glycolysis of pancreatic cancer cells via activation of YAP/HIF-1α.

Pancreatic stellate cells (PSCs), a pivotal component of the tumor microenvironment, contribute to tumor growth and metastasis. PSC-derived factors are essential for triggering the generation and maintenance of cancer stem cells (CSCs). However, the mechanisms by which paracrine signals regulate CSC-like properties such as glycolytic metabolism have not been fully elucidated. Here, we report that two pancreatic cancer cell lines, Panc-1 and MiaPaCa-2, reacted differently when treated with hepatocyte growth factor (HGF) secreted from PSCs. MiaPaCa-2 cells showed little response with regard to CSC-like properties after HGF treatment. We have shown that in Panc-1 cells by activating its cognate receptor c-MET, paracrine HGF resulted in YAP nuclear translocation and HIF-1α stabilization, thereby promoting the expression of CSC pluripotency markers NANOG, OCT-4 and SOX-2 and tumor sphere formation ability. Furthermore, HGF/c-MET/YAP/HIF-1α signaling enhanced the expression of Hexokinase 2 (HK2) and promoted glycolytic metabolism, which may facilitate CSC-like properties. Collectively, our study demonstrated that HGF/c-MET modulates tumor metabostemness by regulating YAP/HIF-1α and may hold promise as a potential therapeutic target against pancreatic cancer.

Cloning and Expression Analysis of the BocMBF1c Gene Involved in Heat Tolerance in Chinese Kale.

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.

H2 S inhibits apo(a) expression and secretion through PKCα/FXR and Akt/HNF4α pathways in HepG2 cells.

Lipoprotein(a) [Lp(a)] is a strong genetic risk factor for coronary heart diseases. However, the metabolism of this protein remains poorly understood. Efficient and specific drugs that can decrease high plasma levels of Lp(a) have not been developed yet. Hydrogen sulfide (H2 S), a member of the gas transmitter family, performs important biological actions, including protection against cardiovascular diseases and maintenance of the lipid metabolism equilibrium in hepatocytes and adipocytes. In this study, we investigated the possible molecular mechanism of H2 S that influences apolipoprotein(a) [apo(a)] biosynthesis. We also determined the effects of H2 S on apo(a) expression and secretion in HepG2 cells as well as the underlying mechanisms. Results showed that H2 S significantly inhibited the expression and secretion levels of apo(a). These effects were attenuated by the PKCα inhibitor and FXR siRNA. H2 S also reduced HNF4α expression and enhanced FXR expression. The Akt inhibitor partially reversed H2 S-induced inhibition of apo(a) and HNF4α expression and apo(a) secretion. This study reveals that H2 S suppressed apo(a) expression and secretion via the PKCα-FXR and PI3K/Akt-HNF4α pathways.

Gli-1 is crucial for hypoxia-induced epithelial-mesenchymal transition and invasion of breast cancer.

Hypoxia can induce HIF-1α expression and promote the epithelial-mesenchymal transition (EMT) and invasion of cancer cells. However, their mechanisms remain unclear. The objective of this study was to evaluate the role of Gli-1, an effector of the Hedgehog pathway, in the hypoxia-induced EMT and invasion of breast cancer cells. Human breast cancer MDA-MB-231 cells were transfected with HIF-1α or Gli-1-specific small interfering RNA (siRNA) and cultured under a normoxic or hypoxic condition. The relative levels of HIF-1α, Gli-1, E-cadherin, and vimentin in the cells were characterized by quantitative RT-PCR and Western blot assays, and the invasion of MDA-MB-231 cells was determined. Data was analyzed by Student T test, one-way ANOVA, and post hoc LSD test or Mann-Whitney U when applicable. We observed that hypoxia significantly upregulated the relative levels of vimentin expression, but downregulated E-cadherin expression and promoted the invasion of MDA-MB-231 cells, associated with upregulated HIF-1α translation and Gil-1 expression. Knockdown of HIF-1α mitigated hypoxia-modulated Gil-1, vimentin and E-cadherin expression, and invasion of MDA-MB-231 cells. Knockdown of Gil-1 did not significantly change hypoxia-upregulated HIF-1α translation but completely eliminated hypoxia-modulated vimentin and E-cadherin expression and invasion of MDA-MB-231 cells. These data indicate that Gil-1 is crucial for hypoxia-induced EMT and invasion of breast cancer cells and may be a therapeutic target for intervention of breast cancer metastasis.

Molecular Cloning, Expression Pattern and Genotypic Effects on Glucoraphanin Biosynthetic Related Genes in Chinese Kale (Brassica oleracea var. alboglabra Bailey).

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.

Projection-based disparity control for toed-in multiview images.

The multiview images captured by toed-in camera array can reproduce the 3D scene vividly with appropriate positive, negative, and zero disparities. However, it is a challenging task to adjust the depth of the scene according to requirements of visual effects. In this paper, we propose a novel disparity control method based on projection to solve this problem. With the relationship between the world coordinate system and camera coordinate system, the zero disparity point in reference view is projected into other views. Thus, disparities of different views are obtained through matched corresponding points and views are shifted with calculated disparities. The proposed method is easy to implement, and the depth of toed-in multiview images can be adjusted as requirements. Experiment results show that the proposed method is effective in comparison to the conventional method, and the processed multiview images present desirable stereoscopic visual quality.

A putative E3 ubiquitin ligase substrate receptor degrades transcription factor SmNAC to enhance bacterial wilt resistance in eggplant.

Bacterial wilt caused by Ralstonia solanacearum is a severe soil-borne disease globally, limiting the production in Solanaceae plants. SmNAC negatively regulated eggplant resistance to Bacterial wilt (BW) though restraining salicylic acid (SA) biosynthesis. However, other mechanisms through which SmNAC regulates BW resistance remain unknown. Here, we identified an interaction factor, SmDDA1b, encoding a substrate receptor for E3 ubiquitin ligase, from the eggplant cDNA library using SmNAC as bait. SmDDA1b expression was promoted by R. solanacearum inoculation and exogenous SA treatment. The virus-induced gene silencing of the SmDDA1b suppressed the BW resistance of eggplants; SmDDA1b overexpression enhanced the BW resistance of tomato plants. SmDDA1b positively regulates BW resistance by inhibiting the spread of R. solanacearum within plants. The SA content and the SA biosynthesis gene ICS1 and signaling pathway genes decreased in the SmDDA1b-silenced plants but increased in SmDDA1b-overexpression plants. Moreover, SmDDB1 protein showed interaction with SmCUL4 and SmDDA1b and protein degradation experiments indicated that SmDDA1b reduced SmNAC protein levels through proteasome degradation. Furthermore, SmNAC could directly bind the SmDDA1b promoter and repress its transcription. Thus, SmDDA1b is a novel regulator functioning in BW resistance of solanaceous crops via the SmNAC-mediated SA pathway. Those results also revealed a negative feedback loop between SmDDA1b and SmNAC controlling BW resistance.