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Circular RNAs (circRNAs) are widely expressed in cancer tissues and participate in modulating the progression of malignant tumors, playing a pro- or anti-cancer role. This work is conducted to probe the precise role of circ_0000467 in colorectal cancer (CRC) and its regulatory mechanism. The differentially expressed circRNAs in CRC tissues and paracancerous tissues were screened by bioinformatics analysis. The expression levels of circ_0000467, miR-651-5p and DNA methyltransferases 3B (DNMT3B) mRNA in CRC tissues and cells were detected by qRT-PCR. circ_0000467 knockdown cell model was constructed to investigate the effects of circ_0000467 on CRC cell growth, migration and invasion by CCK-8 and Transwell experiments. Western blot was performed to examine DNMT3B protein expression in CRC cells. Dual-luciferase reporter gene experiment was executed to validate the targeting relationship between circ_0000467 and miR-651-5p, miR-651-5p and DNMT3B. Circ_0000467 expression and DNMT3B mRNA expression were increased and miR-651-5p expression was down-regulated in CRC tissues and cell lines. Knockdown of circ_0000467 repressed CRC cell growth, migration and invasion. Dual-luciferase reporter gene experiments validated that miR-651-5p was a direct target of circ_0000467 and miR-651-5p could specifically bind with DNMT3B 3'UTR. Functional compensation experiments showed that the regulatory effect of circ_0000467 on CRC cells' behaviors could be partially counteracted by miR-651-5p. Circ_0000467 may enhance the growth and metastasis of CRC cells by targeting miR-651-5p and up-regulating DNMT3B expression. Circ_0000467 may be a potential diagnostic biomarker and therapeutic target for CRC.

Intestinal barrier dysfunction is inflammatory bowel disease's hallmark. Berberine (BBR) has manifested its anti-inflammatory properties in colitis. For exploring the molecular mechanism of BBR's impacts on colitis, application of a dextran sodium sulfate-induced mouse colitis

Background Circular RNAs (circRNAs) are crucial in the regulation of gene expression and biological processes. However, in colorectal cancer, the expression characteristics and biological function of circRNA_0006174 (circ_0006174) is not fully understood. This work is aimed to investigate the biological function of circ_0006174 in colorectal cancer and its molecular mechanism. Methods Circ_0006174, microRNA-142-3p and X-linked inhibitor of apoptosis expression levels were detected in colorectal cancer tissues and cells using quantitative real-time polymerase chain reaction analysis or Western blot. The effects of circ_0006174 on colorectal cancer cell proliferation, apoptosis, migration and invasion were detected using the cell counting kit-8 method, bromodeoxyuridine experiments, flow cytometry analysis and Transwell experiments. The targeting relationship among circ_0006174, microRNA-142-3p and X-linked inhibitor of apoptosis was analysed by bioinformatics prediction, dual-luciferase reporter experiment and RNA immunoprecipitation experiment. Results Circ_0006174 was up-regulated in colorectal cancer tissues as well as in cell lines, and its high expression was remarkably associated with enlarged tumour volume and advanced tumour, node, metastasis stage of the patients. Circ_0006174 overexpression enhanced colorectal cancer cell proliferation, migration and invasion, and inhibited colorectal cancer cell apoptosis; while knocking down circ_0006174 caused the opposite effects. Circ_0006174 directly targeted and negatively regulated microRNA-142-3p expression, and X-linked inhibitor of apoptosis, a target gene of microRNA-142-3p, could be indirectly and positively modulated by circ_0006174. Conclusion Circ_0006174 facilitates colorectal cancer cell proliferation, migration and invasion, and represses colorectal cancer cell apoptosis by regulating microRNA-142-3p/X-linked inhibitor of apoptosis axis.

Circular RNAs (circRNAs) are novel RNA transcripts that participate in cancer development. Nonetheless, in colorectal cancer (CRC), the information ~circRNA expression and function is largely unknown. The present study aimed to investigate the expression, function and underlying mechanism of circ_0006174 in CRC. Reverse transcription‑quantitative PCR analysis was performed to detect circ_0006174, miR‑1205 and calcium‑binding epidermal growth factor domain‑containing protein 1 (CCBE1) expression levels in CRC tissues and cell lines. Circ_0006174 knockdown CRC cell models were established. CCK‑8, TUNEL and Transwell methods were utilized to explore the function of circ_0006174 on the malignant phenotype of CRC cells. Moreover, a xenograft nude mouse model was constructed to verify the effects of circ_0006174 on lung metastasis

Objective: Through the research on the application of ultrasound image technology in the diagnosis and treatment of functional dyspepsia, the value of ultrasound image technology in the treatment of functional dyspepsia is discussed, which verifies the effectiveness and superiority of ultrasound image technology in the diagnosis and treatment of functional dyspepsia. Methods: In this experiment, functional dyspepsia patients who are treated in the Department of Gastroenterology of a comprehensive third grade a hospital and healthy volunteers are taken as the research objects. Among them, healthy adults are in group A, i. e., control group. There is no obvious digestive tract disease within 2 years. Patients with functional dyspepsia are in group B. After that, the liquid standard nutrition meal is prepared. Both groups need to carry out liquid application meal load test according to the steps. Then, the initial and maximum satiety intake of each group is recorded, and ultrasound imaging technology is used to locate the distal and proximal gastric sections of the two groups. Then, the area of the distal and proximal stomach is recorded at the time of initial satiety, the time of maximum satiety and the time after drinking. After that, according to the area, volume and other relevant data are calculated, the data are input into the database, and SPSS22.0 is used to analyze the data. Results: The time of proximal gastric semi emptying is compared between group B and group A. It is found that the time of proximal gastric semi emptying is longer in group B. In addition, it is found that the time of distal gastric semi emptying in group B is longer than that in group A. There is significant difference in the time of proximal gastric semi emptying and distal gastric semi emptying between the two groups (P < 0.05). In group B, when the initial satiety of liquid standard diet is achieved, the intake is significantly less than that of healthy adults. It is found that the proximal gastric volume of group B is smaller than that of the control group. The intake and proximal gastric volume of the two groups are statistically significant (P < 0.05). There are significant differences between the two groups in the maximum satiety, 30 minutes after meal and 60 minutes after meal (P < 0.05). Conclusion: Ultrasonic imaging technology can monitor the patients' stomach volume and the maximum and minimum intake in real time. Through monitoring, the sensitivity of patients' stomach and some functional abnormalities can be known in time, which is of great significance for the treatment and diagnosis of functional dyspepsia.

Circular RNAs (circRNAs) feature prominently in regulating the malignant biological behaviors of colorectal cancer (CRC), including cell viability, cell cycle progression, apoptosis, migration, invasion, and so on. This study is performed to probe into the biological function and molecular mechanism of circ_0087862 in CRC. The expression profile of GSE138589 was available from Gene Expression Omnibus (GEO), and the differentially expressed circRNAs were analyzed by GEO2R. The expression of circ_0087862, miR‐142‐3p, and BACH1 mRNA in CRC tissues and cells was measured by qRT‐PCR. CCK‐8 assay was employed to determine the proliferation of CRC cells. Scratch wound healing and transwell assays were used to examine the migration and invasion of CRC cells. The targeting relationships between circ_0087862 and miR‐142‐3p, and between miR‐142‐3p and BACH1 3′UTR were verified by dual‐luciferase reporter gene assay and RIP assay. BACH1 protein expression was probed by western blot. Circ_0087862 was highly expressed in CRC tissues and cell lines. Knocking down circ_0087862 significantly restrained the multiplication, migration and invasion of CRC cells. miR‐142‐3p inhibition weakened the impact of circ_0087862 knockdown on CRC cells. Circ_0087862 regulated BACH1 expressions by targeting miR‐142‐3p. Circ_0087862 regulates BACH1 expressions through sponging miR‐142‐3p, and promotes the proliferation, migration, and invasion of CRC cells.

To solve the problem that the individual differences and the measurement errors affect the accuracy of life estimation in accelerated degradation test, the inverse Gauss process with stochastic parameters is applied in the accelerated degradation test with the consideration of the influence of individual differences, and the analysis of measurement uncertainty is carried out. An inverse Gauss accelerated degradation model considering both individual differences and measurement errors is established. In the maximum likelihood estimation of parameters, Genetic Algorithm and Monte Carlo integral are used to solve the problems caused by complex integral and the unobservable measurement errors in the calculation process. Finally, the proposed method is verified by the Monte Carlo simulation under the constant accelerated stress and step accelerated stress and the illustrative example of electrical connectors under the constant acceleration stress, respectively. The results show that the modeling tool is useful for improving the accuracy of the life prediction and the reliability evaluation.

A multi-objective optimization method for constant stress accelerated degradation test is proposed in order to solve the problem of different or even conflicted test configuration under different optimization objectives. The inverse Gaussian process is used as a degradation model, and the unknown parameters are solved by maximum likelihood estimation. The two optimization criteria of the maximum determinant of the information matrix and the minimum asymptotic variance of P-quantile are considered. The improved multi-objective particle swarm optimization algorithm is proposed to search test optimal configuration, and the Pareto solution set for dual-objectives is obtained. Finally, the effectiveness of the method is illustrated by a group of examples of electrical connectors. Compared with the single-objective optimization design, the proposed method is more reasonable and convenient for test configuration. The performance index of the test function indicates that the optimal algorithm we proposed has some obvious advantages over the NSGA-II in diversity and convergence of the Pareto solutions and it is significant in guiding engineering practice.

The aim of this study was to explore colorectal tumor-associated macrophage (TAM) biomarkers for early diagnosis and surveillance of colorectal cancer (CRC). We used bioinformatic methods to screen array expression data of CRC-related macrophages (GEO: GSE29214) to detect the differentially expressed genes (DEGs) between CRC-related macrophages and normal control cells. We found 431 DEGs in TAMs compared with the control group; 399 were up-regulated and 32 were down-regulated. A functional enrichment analysis showed that the DEGs were involved in positive regulation of the ERK1 and ERK2 cascade, cell activation involved in the immune response, cytokine-mediated signaling pathway, and receptor activity, all of which were significantly enriched. We constructed a protein-protein interaction (PPI) network to identify hub genes. We identified 10 hub genes: ITGB2, ITGAM, C3AR1, PTAFR, C3, CYBB, FCER1G, PLAU, STOM, and GPR84, in the PPI network. We verified the results using array expression data of peripheral blood mononuclear cells (GEO: GSE47756). The results showed that the expression trends of CYBB, PLAU, and STOM were consistent with those found in the GSE29214 dataset. Further verification with The Cancer Genome Atlas and Human Protein Atlas showed that the high expression of PLAU in TAMs was statistically significant (P

Via applying the mixed-ligand approach, a new Cu(II)-bearing coordination polymer (CP) with the chemical formula of [Cu(1,4-chdc)(L)(H2O)]n (1, (1,4-H2chdc = 1,4-cyclohexanedicarboxylic acid, L = 2-(4-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline) has been successfully prepared under hydrothermal condition. The single-crystal X-ray diffraction study shows that CP 1 shows a 1D chain-like structure which is further extended into a 2D supramolecular network via the H-bond interactions. Furthermore, a sonochemical treatment method was applied to produce the nanosized 1 with the size distribution around 200 nm. To detect the cell proliferation of MGC-803 (human gastric cancer cell lines) after treated with nano 1, the Cell Counting Kit-8 (CCK-8) assay was performed in this experiment. Besides, the MGC-803 cell apoptosis was determined by Annexin V-FITC/PI (FITC = fluorescein isothiocyanate, PI = propidium iodide) apoptosis detection kit in flow cytometer and western blot after treated with nano 1. A new Cu(II)-bearing coordination polymer has been prepared under hydrothermal conditions. A sonochemical treatment method was applied to produce the nanosized 1 with the size distribution around 200 nm. The anti-cancer activity of nano 1 has been evaluated via the Cell Counting Kit-8 (CCK-8) assay and Annexin V-FITC/PI.

Circular RNAs (circRNAs) are key regulators in the development of many cancers. The present study was aimed to investigate the mechanism by which circ_0007919 affected colorectal cancer (CRC) progression.The differentially expressed circRNA was screened out by analyzing the expression profile of circRNAs of CRC tissues. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed for detecting the expressions of circ_0007919, miR-942-5p, and ten-eleven translocation 1 (TET1) mRNA in CRC tissues and cell lines. Cell growth and migration were assessed by cell counting kit-8 (CCK-8) 5-bromo-2'-deoxyuridine (BrdU) and scratch assays. Bioinformatics analysis and dual-luciferase reporter assay were conducted to predict and validate the targeted relationships between circ_0007919 and miR-942-5p, as well as between miR-942-5p and TET1 mRNA. Besides, Western blot was conducted for detecting TET1 protein expression in CRC cells. It was revealed that, in CRC tissues and cell lines, circ_0007919 and TET1 expressions were reduced whereas miR-942-5p expression was enhanced. It was also revealed that circ_0007919 overexpression markedly suppressed CRC cell growth and migration. In addition, circ_0007919 could competitively bind with miR-942-5p to increase the expression of miR-942-5p's target gene TET1. Collectively, circ_0007919 inhibits CRC cell growth and migration via regulating the miR-942-5p/TET1 axis. This study helps to better understand the molecular mechanism of CRC progression.

Cancer stem cells (CSCs) in gastric cancer (GC) have been established recently as key therapeutic targets for the successful treatment of GC. Emerging evidence suggests that both CSCs and cancer cells should be eradicated to achieve optimal therapeutic efficacy. In the present study, salinomycin, which has been reported to kill CSCs, was used in combination with docetaxel, a chemotherapeutic drug that is used as first-line therapy in GC, to eradicate both GC stem cells (SCs) and cancer cells. Salinomycin and docetaxel were loaded separately into poly(D,L-lactic-co-glycolic acid)-poly(ethylene glycol) nanoparticles of ∼140 nm with a narrow size distribution, high drug loading, and sustained drug release. GC SCs were isolated by magnetic-activated cell sorting on the basis of CD44 expression as the CSC phenotype. CD44 GC SCs showed the characteristics of CSCs, including increased SC gene expression, tumorsphere formation capacity, and tumorigenicity in nude mice. We found that both salinomycin and salinomycin-loaded nanoparticles (salinomycin-NPs) could selectively eradicate GC SCs, as reflected by reduced tumorsphere formation capacity and the frequency of CD44 GC cells, whereas docetaxel and docetaxel-loaded nanoparticles (docetaxel-NPs) could significantly eradicate GC cells. In nude mice bearing GC xenografts, salinomycin-NPs and salinomycin significantly decreased the intratumor population of GC SCs. Notably, salinomycin-NPs combined with docetaxel-NPs suppressed tumor growth more effectively than did salinomycin combined with docetaxel, single salinomycin-NPs, or docetaxel-NPs. Therefore, salinomycin-NPs combined with docetaxel-NPs represent a promising strategy for the treatment of GC by eradicating both GC SCs and cancer cells.

Stomach adenocarcinoma (STAD) is one of the leading causes of cancer morbidity and mortality worldwide. The present study aimed to identify the microRNAs associated with STAD survival time. The clinical information and microarray miRNA and mRNA expression profiles of STAD patients were downloaded from The Cancer Genome Atlas. Differential expression (DE) analysis was performed to identify DEmiRNAs and DEmRNAs in STAD. The DEmiRNAs associated with the survival time of patients with STAD were identified through DE analysis, negative correlation pair analysis, miRNA target gene prediction, univariate Cox regression analysis and Kaplan-Meier analysis. The functions of the target genes of the DEmiRNAs were predicted with Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. A total of 355 DEmiRNAs and 1,722 DEmRNAs were identified between STAD and normal tissues. A total of 5 DEmiRNAs were identified to be associated with STAD survival, including 4 risk-associated DEmiRNAs (miR-30a, -143, -145 and -133b) and 1 protective DEmiRNA (miR-135b). The target DEmRNAs were significantly enriched for DNA metabolic process in the biological process GO category, and in KEGG cell cycle signaling pathways. Kaplan-Meier curves indicated that the overall survival time in the miR-30a, -143, -145 and -133b high expression groups was significantly shorter than that in the low expression groups, whereas the survival time was prolonged in the miR-135b high expression group compared with that in the low expression group. Therefore, miR-30a, -143, -145, -133b and -135b may be involved in the tumorigenesis and development of STAD, and may be potential biomarkers for its early diagnosis and prognosis.

Background: Short-term use of standard-dose proton pump inhibitors (PPIs) is the first-line initial non-eradication treatment for duodenal ulcer (DU), but the choice on individual PPI drug is still controversial. The purpose of this study is to compare the efficacy, safety, and cost-effectiveness of standard-dose PPI medications in the initial non-eradication treatment of DU. Methods: We searched PubMed, Embase, Cochrane Library, Clinicaltrials.gov, China National Knowledge Infrastructure, VIP database, and the Wanfang database from their earliest records to September 2017. Randomized controlled trials (RCTs) evaluating omeprazole (20 mg/day), pantoprazole (40 mg/day), lansoprazole (30 mg/day), rabeprazole (20 mg/day), ilaprazole (10 mg/day), ranitidine (300 mg/day), famotidine (40 mg/day), or placebo for DU were included. The outcomes were 4-week ulcer healing rate (4-UHR) and the incidence of adverse events (AEs). A network meta-analysis (NMA) using a Bayesian random effects model was conducted, and a cost-effectiveness analysis using a decision tree was performed from the payer's perspective over 1 year. Results: A total of 62 RCTs involving 10,339 participants (eight interventions) were included. The NMA showed that all the PPIs significantly increased the 4-UHR compared to H2 receptor antagonists (H2RA) and placebo, while there was no significant difference for 4-UHR among PPIs. As to the incidence of AEs, no significant difference was observed among PPIs, H2RA, and placebo during 4-week follow-up. Based on the costs of both PPIs and management of AEs in China, the incremental cost-effectiveness ratio per quality-adjusted life year (in US dollars) for pantoprazole, lansoprazole, rabeprazole, and ilaprazole compared to omeprazole corresponded to $5134.67, $17801.67, $25488.31, and $44572.22, respectively. Conclusion: Although the efficacy and tolerance of different PPIs are similar in the initial non-eradication treatment of DU, pantoprazole (40 mg/day) seems to be the most cost-effective option in China.

Gastric cancer, due to its high incidence rate, is the second leading cause of cancer-related mortality worldwide. Chemotherapy is an important component of the multimodal treatment for gastric cancer; however, a significant impediment to successful treatment is multidrug resistance (MDR) in patients with gastric cancer. In the present study, the protein profiles of the MDR cell line, SGC7901/DDP, and its parental cell line, SGC7901, were comparatively analyzed through an iTRAQ-based quantitative proteomics technique. The protein tetraspanin-8 (TSPAN8) was found to be highly expressed in the SGC7901/DDP cells. To examine the role of TSPAN8 in the MDR of SGC7901/DDP cells, we increased cell sensitivity to drugs by increasing apoptosis. Additionally, the silencing of TSPAN8 downregulated Wnt pathway activity, β-catenin expression and β-catenin transfer to the nucleus. TSPAN8 was found to bind to NOTCH2, facilitating its mediation of the Wnt/β-catenin pathway by regulating β-catenin expression. Overall, the suppression of TSPAN8 expression may prove to be a promising strategy which may aid in the development of novel gastric cancer therapeutic drugs.

The Arabidopsis transparent testa (tt) mutant tt19-4 shows reduced seed coat colour, but stains darkly with DMACA and accumulates anthocyanins in aerial tissues. Positional cloning showed that tt19-4 was allelic to tt19-1 and has a G-to-T mutation in a conserved 3-domain in the TT19-4 gene. Soluble and unextractable seed proanthocyanidins and hydrolysis of unextractable proanthocyanidin differ between wild-type Col-4 and both mutants. However, seed quercetins, unextractable proanthocyanidin hydrolysis, and seedling anthocyanin content, and flavonoid gene expres- sion differ between tt19-1 and tt19-4. Transformation of tt19-1 with a TT19-4 cDNA results in vegetative anthocya- nins, whereas TT19-4 cDNA cannot complement the proanthocyanidin and pale seed coat phenotype of tt19-1. Both recombinant TT19 and TT19-4 enzymes are func- tional GSTs and are localized in the cytosol, but TT19 did not function with wide range of flavonoids and natural products to produce conjugation products. We suggest that the dark seed coat of Arabidopsis is related to soluble proanthocyanidin content and that quercetin holds the key to the function of TT19. In addition, TT19 appears to have a5 GSH-binding domain influencing both anthocyanin and proanthocyanidin accumulation and a 3 domain affecting proanthocyanidin accumulation by a single amino acid substitution.

Flavonoids are widely distributed in plants and play important roles in human and animal health and nutrition. Model plants with discernible flavonoid phenotypes, such as Arabidopsis seed patterning lines, are valuable tools that can provide avenues for understanding flavonoid and proanthocyanidin accumulation patterns in crops. Here, we characterize the GARP family gene, KAN4, which earlier was known for its role in defining the boundary of the seed integument layers in Arabidopsis. In this report, KAN4 is shown to broadly control the flavonoid pathway in Arabidopsis seed. Loss-of-function T-DNA mutants show reduced transcript abundance for most flavonoid and proanthocyanidin genes in young siliques and decreased flavonols and variable proanthocyanidin content in mature seed. KAN4 was localized to the nucleus and could specifically bind with promoters of early and late flavonoid biosynthetic genes and PA regulatory genes. Activated over-expression of KAN4 led to the discovery of the first novel dominant Arabidopsis transparent testa mutant, sk21-D. Two KAN4 transcript splice variants with identical MYB-like B-motifs were highly expressed in sk21-D and equivalently designed activation atk4-OE lines. This extreme dual expression resulted in large, light- and dark-coloured patches on seed coats of sk21-D and atk4-OE lines, but not in non-activated over-expression lines. Flavonoid and proanthocyanidin contents and transcript amounts for genes involved in flavonoid biosynthesis also were reduced in KAN4 activation lines. These results confirm that KAN4 is a regulatory protein which modulates the content of flavonols and PA in Arabidopsis seeds.

Primary intestinal NK/T cell lymphoma is extremely rare and early diagnosis is frequently difficult. The aim of this study is to investigate the clinicopathological findings, immunophenotype, and T cell receptor (TCR) γ gene rearrangement of primary intestinal NK/T cell lymphomas in 25 Chinese cases.Clinical data of the 25 cases were analyzed. Immunohistochemistry for immunophenotype, in situ hybridization for EBER, and polymerase chain reaction for TCR γ gene rearrangement were investigated. Survival curves according to clinical characteristics were analyzed.The median age was 33 years and the median survival was 7 months. The common symptoms consisted of abdominal pain, fever, marasmus, diarrhea, and hematochezia. Endoscopically, the tumors were mainly featured by focal, multifocal or diffuse irregular ulcers, which most frequently emerged in the ascending colon. Histologically, the tumors were characterized by the proliferation of pleomorphic atypical lymphoid cells (ALCs), necrosis, lympho-epithelial lesions, and mixed inflammatory infiltration. The positive frequency of CD3ε was 88.2%, of CD56 was 84%, granzyme B was 90%, and EBER was 84.2%. A total of 12 out of 14 cases (85.7%) highly expressed Ki67. The negative prognostic factors for survival were Ann Arbor stage IIIE or IVE (P = 0.039) and more than one extranodal site of disease (P = 0.019).Primary intestinal NK/T cell lymphomas most frequently favor young people and have a poor prognosis. Due to the nonspecific clinical and endoscopic findings, it is difficult to distinguish intestinal NK/T cell lymphomas from inflammatory and infectious disorders. Histopathology, immunophenotype, and DNA study play key roles in differential diagnosis.

The Arabidopsis transparent testa (tt) mutant tt19-4 shows reduced seed coat colour, but stains darkly with DMACA and accumulates anthocyanins in aerial tissues. Positional cloning showed that tt19-4 was allelic to tt19-1 and has a G-to-T mutation in a conserved 3'-domain in the TT19-4 gene. Soluble and unextractable seed proanthocyanidins and hydrolysis of unextractable proanthocyanidin differ between wild-type Col-4 and both mutants. However, seed quercetins, unextractable proanthocyanidin hydrolysis, and seedling anthocyanin content, and flavonoid gene expression differ between tt19-1 and tt19-4. Transformation of tt19-1 with a TT19-4 cDNA results in vegetative anthocyanins, whereas TT19-4 cDNA cannot complement the proanthocyanidin and pale seed coat phenotype of tt19-1. Both recombinant TT19 and TT19-4 enzymes are functional GSTs and are localized in the cytosol, but TT19 did not function with wide range of flavonoids and natural products to produce conjugation products. We suggest that the dark seed coat of Arabidopsis is related to soluble proanthocyanidin content and that quercetin holds the key to the function of TT19. In addition, TT19 appears to have a 5' GSH-binding domain influencing both anthocyanin and proanthocyanidin accumulation and a 3' domain affecting proanthocyanidin accumulation by a single amino acid substitution.

Flavonoids are widely distributed in plants and play important roles in human and animal health and nutrition. Model plants with discernible flavonoid phenotypes, such as Arabidopsis seed patterning lines, are valuable tools that can provide avenues for understanding flavonoid and proanthocyanidin accumulation patterns in crops. Here, we characterize the GARP family gene, KAN4, which earlier was known for its role in defining the boundary of the seed integument layers in Arabidopsis. In this report, KAN4 is shown to broadly control the flavonoid pathway in Arabidopsis seed. Loss-of-function T-DNA mutants show reduced transcript abundance for most flavonoid and proanthocyanidin genes in young siliques and decreased flavonols and variable proanthocyanidin content in mature seed. KAN4 was localized to the nucleus and could specifically bind with promoters of early and late flavonoid biosynthetic genes and PA regulatory genes. Activated over-expression of KAN4 led to the discovery of the first novel dominant Arabidopsis transparent testa mutant, sk21-D. Two KAN4 transcript splice variants with identical MYB-like B-motifs were highly expressed in sk21-D and equivalently designed activation atk4-OE lines. This extreme dual expression resulted in large, light- and dark-coloured patches on seed coats of sk21-D and atk4-OE lines, but not in non-activated over-expression lines. Flavonoid and proanthocyanidin contents and transcript amounts for genes involved in flavonoid biosynthesis also were reduced in KAN4 activation lines. These results confirm that KAN4 is a regulatory protein which modulates the content of flavonols and PA in Arabidopsis seeds.