Integrated transcriptome and metabolome analysis reveals anthocyanin biosynthesis mechanisms in pepper (Capsicum annuum L.) leaves under continuous blue light irradiation.

BACKGROUND: Different metabolic compounds give pepper leaves and fruits their diverse colors. Anthocyanin accumulation is the main cause of the purple color of pepper leaves. The light environment is a critical factor affecting anthocyanin biosynthesis. It is essential that we understand how to use light to regulate anthocyanin biosynthesis in plants. RESULT: Pepper leaves were significantly blue-purple only in continuous blue light or white light (with a blue light component) irradiation treatments, and the anthocyanin content of pepper leaves increased significantly after continuous blue light irradiation. This green-to-purple phenotype change in pepper leaves was due to the expression of different genes. We found that the anthocyanin synthesis precursor-related genes PAL and 4CL, as well as the structural genes F3H, DFR, ANS, BZ1, and F3'5'H in the anthocyanin synthesis pathway, had high expression under continuous blue light irradiation. Similarly, the expression of transcription factors MYB1R1-like, MYB48, MYB4-like isoform X1, bHLH143-like, and bHLH92-like isoform X3, and circadian rhythm-related genes LHY and COP1, were significantly increased after continuous blue light irradiation. A correlation network analysis revealed that these transcription factors and circadian rhythm-related genes were positively correlated with structural genes in the anthocyanin synthesis pathway. Metabolomic analysis showed that delphinidin-3-O-glucoside and delphinidin-3-O-rutinoside were significantly higher under continuous blue light irradiation relative to other light treatments. We selected 12 genes involved in anthocyanin synthesis in pepper leaves for qRT-PCR analysis, and the accuracy of the RNA-seq results was confirmed. CONCLUSIONS: In this study, we found that blue light and 24-hour irradiation together induced the expression of key genes and the accumulation of metabolites in the anthocyanin synthesis pathway, thus promoting anthocyanin biosynthesis in pepper leaves. These results provide a basis for future study of the mechanisms of light quality and photoperiod in anthocyanin synthesis and metabolism, and our study may serve as a valuable reference for screening light ratios that regulate anthocyanin biosynthesis in plants.

A preliminary analysis of microRNA as potential clinical biomarker for schizophrenia.

MicroRNAs (miRNA, miR) have been implicated as promising blood-based biomarkers for schizophrenia patients. This study aimed to clinically validate miRNA as potential schizophrenia biomarkers. Plasma levels of 10 miRNAs were analyzed using qPCR in a cohort of 61 schizophrenia patients and 62 normal controls, as well as 25 patients particularly selected for a six-week antipsychotic treatment course. Positive And Negative Syndrome Scale (PANSS), Global Assessment Scale (GAS) and Clinical Global Impression (CGI) were administered to assess the clinical symptoms. The results demonstrated that a panel of miRNAs consisting of miR-30e, miR-181b, miR-34a, miR-346 and miR-7 had significantly increased expression levels with significant combined diagnostic value (AUC:0.713; sensitivity:35.5%; specificity:90.2%). In response to pharmacological treatment, expression levels of miR-132, miR-181b, miR-432 and miR-30e were significantly decreased. In addition, the improvement of clinical symptomatology was significantly correlated with the changes of miR-132, miR-181b, miR-212 and miR-30e expression levels. Furthermore, the decreases of plasma levels of miR-132 and miR-432 were significantly greater in high-effect subgroup than those in low-effect subgroup after six-week treatment course. We conclude that miR-30e, miR-181b, miR-34a, miR-346 and miR-7 combined as a panel are potentially useful non-invasive biomarkers for schizophrenia diagnosis. Markers miR-132, miR-181b, miR-30e and miR-432 are potential indicators for symptomatology improvements, treatment responses and prognosis for schizophrenia patients.

A multi-omics approach identifies bHLH71-like as a positive regulator of yellowing leaf pepper mutants exposed to high-intensity light.

Light quality and intensity can have a significant impact on plant health and crop productivity. Chlorophylls and carotenoids are classes of plant pigments that are responsible for harvesting light energy and protecting plants from the damaging effects of intense light. Our understanding of the role played by plant pigments in light sensitivity has been aided by light-sensitive mutants that change colors upon exposure to light of variable intensity. In this study, we conducted transcriptomic, metabolomic, and hormone analyses on a novel yellowing mutant of pepper (yl1) to shed light on the molecular mechanism that regulates the transition from green to yellow leaves in this mutant upon exposure to high-intensity light. Our results revealed greater accumulation of the carotenoid precursor phytoene and the carotenoids phytofluene, antheraxanthin, and zeaxanthin in yl1 compared with wild-type plants under high light intensity. A transcriptomic analysis confirmed that enzymes involved in zeaxanthin and antheraxanthin biosynthesis were upregulated in yl1 upon exposure to high-intensity light. We also identified a single basic helix-loop-helix (bHLH) transcription factor, bHLH71-like, that was differentially expressed and positively correlated with light intensity in yl1. Silencing of bHLH71-like in pepper plants suppressed the yellowing phenotype and led to reduced accumulation of zeaxanthin and antheraxanthin. We propose that the yellow phenotype of yl1 induced by high light intensity could be caused by an increase in yellow carotenoid pigments, concurrent with a decrease in chlorophyll accumulation. Our results also suggest that bHLH71-like functions as a positive regulator of carotenoid biosynthesis in pepper.

Studying the effect of light intensity on the photosynthetic mechanism of pepper leaf yellowing mutants by proteomics and phosphoproteomics.

The leaf is an important plant organ and is closely related to agricultural yield. Photosynthesis plays a critical role in promoting plant growth and development. Understanding the mechanism of leaf photosynthesis regulation will help improve crop yield. In this study, the pepper yellowing mutant was used as the experimental material, and the photosynthetic changes of pepper leaves (yl1 and 6421) under different light intensities were analyzed by chlorophyll fluorimeter and photosynthesis meter. Changes in proteins and enrichment of phosphopeptides in pepper leaves were determined. The results showed that different light intensities had significant effects on the chlorophyll fluorescence and photosynthetic parameters of pepper leaves. The differentially expressed proteins (DEPs) and differentially expressed phosphorylated proteins (DEPPs) were mainly involved in photosynthesis, photosynthesis-antenna proteins, and carbon fixation in photosynthetic organisms. In yl1 leaves, the phosphorylation levels of photosynthesis and photosynthesis-antenna proteins LHCA2, LHCA3, PsbC, PsbO, and PsbP were lower under low light treatment, but significantly higher under high light intensity compared with wild-type leaves. In addition, many proteins involved in the carbon assimilation pathway, including TKT, Rubisco, and PGK, were phosphorylated, and this modification level was significantly higher in yl1 than in the wild type under high light intensity. These results provide a new perspective for studying the photosynthesis mechanism of pepper under different light intensities.

Clinicopathological features and prognosis of gastric mixed adenoneuroendocrine carcinoma.

Gastric mixed adenoneuroendocrine carcinomas (MANECs) are rare malignant tumors. This study aimed to investigate the clinicopathological features, diagnosis, prognosis, and treatment outcome in gastric MANECs patients. Clinicopathological data and the archived slides of 40 cases of MANEC patients were retrospectively reviewed. Immunohistochemistry (IHC) staining was performed to detect expression of synaptophysin (Syn), chromogranin A (CgA), CD56, CKpan, CK7, CK8/18, carcinoembryonic antigen (CEA), CK5/6, P40 and Ki-67. Hematoxylin and eosin staining demonstrated exocrine and neuroendocrine components, each accounting for at least 30% of the whole lesion. Exocrine components diffusely expressed epithelial markers CKpan, CK7, CK8/18, and CEA and endocrine components widely expressed at least one of the markers Syn, CgA, and CD56. Ki-67 index and mitosis determined the endocrine component grade as G3. Thirty-three of 40 patients were successfully followed up for 3 to 105 months with median survival of 12 months. Survival analysis showed a significant difference in prognosis with regard to patient's age, disease stage, tumor relapse status, and distant metastasis status. In conclusion, patient's age, disease stage, tumor relapse status, and distant metastasis status are important contributors to poor prognosis. Old patients with advanced stage, recurrence, or metastasis to the liver, pancreas or other distant organs show a poor prognosis.

MicroRNA-486 as a Biomarker for Early Diagnosis and Recurrence of Non-Small Cell Lung Cancer.

BACKGROUND: Non-small cell lung cancer (NSCLC) is a leading cause of cancer death worldwide. Early diagnosis is essential for improvements of prognosis and survival of the patients. Currently, there is no effective biomarker available in clinical settings for early detection of lung cancer. Altered expressions in many cancer types including NSCLC and stable existence in plasma make microRNAs (miRNAs) a group of potentially useful biomarkers for clinical assessments of patients with NSCLC. OBJECTIVES: To evaluate the potential values of miRNAs as blood-based biomarkers for early diagnosis and prognosis in NSCLC patients. METHODS: Peripheral blood samples from healthy volunteers and early-staged NSCLC patients before and after surgery were collected, and plasma was separated. Expression of ten miRNAs in the plasma and tumor sections of the patients was detected by quantitative real-time polymerase chain reaction. RESULTS: MiRNA (miR)-486 and miR-150 were found to significantly distinguish lung cancer patients from healthy volunteers. Area under curve of miR-486 and miR-150 were 0.926 (sensitivity, 0.909; specificity, 0.818) and 0.752 (sensitivity, 0.818; specificity, 0.818), respectively. In response to therapy, patients with down-regulated miR-486 expression showed prolonged recurrence-free survival than those with un-reduced miR-486 expression (median, unreached vs. 19 months; hazard ratio, 0.1053; 95% confidence interval, 0.01045 to 1.060; P=0.056). CONCLUSIONS: The results suggest that miR-486 and miR-150 could be potential blood-based biomarkers for early diagnosis of NSCLC. Monitoring change of miR-486 expression in plasma might be an effective and non-invasive method for recurrence prediction of early-staged NSCLC patients.

Aberrant microRNA expression in peripheral plasma and mononuclear cells as specific blood-based biomarkers in schizophrenia patients.

Findings from multiple studies on microRNA (miRNA) expression profiling in schizophrenia patients have produced conflicting results. In order to investigate miRNA as specific biomarkers in the peripheral plasma and peripheral blood mononuclear cells (PBMC) of schizophrenia patients, expression levels of the nine most frequently reported schizophrenia-associated miRNA (miR-30e, miR-34a, miR-181b, miR-195, miR-346, miR-432, miR-7, miR-132 and miR-212) were examined in the peripheral plasma and PBMC in 25 schizophrenia patients and 13 healthy controls using quantitative real-time reverse transcription polymerase chain reaction. We observed significantly increased expressions of miR-132, miR-195, miR-30e and miR-7 in plasma samples (p<0.05 to p<0.001), and miR-212, miR-34a and miR-30e in PBMC samples (p<0.05 to p<0.01). Receiver operating characteristic curve analysis revealed that the area under the curve (AUC) of miR-30e in plasma was 0.767 (95% confidence interval [CI] 0.608-0.926) with sensitivity and specificity of 90.90% and 60.00% respectively, and the AUC of miR-30e in PBMC was 0.756 (95% CI 0.584-0.929) with sensitivity and specificity of 81.80% and 68.00%, respectively. Logistic regression analysis demonstrated that miR-30e in plasma was more sensitive to differentiate schizophrenia patients from normal controls than miR-30e in PBMC. Our findings indicate that miRNA expression is more significant in plasma than in PBMC, and suggest that miR-30e in plasma may be a more sensitive biomarker for schizophrenia diagnosis, although its aberrant expression can be detected in both plasma and PBMC.

Differential expression of microRNA in peripheral blood mononuclear cells as specific biomarker for major depressive disorder patients.

Currently, diagnosis and treatment of major depressive disorder (MDD) are based on the patients' description of symptoms, mental status examinations, and clinical behavioral observations, which increases the chance of misdiagnosis. There is a serious need to find a practical biomarker for the proper diagnosis of MDD. This study aimed to explore the possibility of microRNA (miRNA) in peripheral blood mononuclear cells (PBMCs) as specific blood-based biomarker for MDD patients. By using an Affymetrix array that covers 723 human miRNAs, we identified 26 miRNAs with significant changes in expression in PBMCs of MDD patients. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis in a larger cohort of 81 MDD patients and 46 healthy controls confirmed that the expression levels of 5 miRNAs (miRNA-26b, miRNA-1972, miRNA-4485, miRNA-4498, and miRNA-4743) were up-regulated. By receiver operating characteristic (ROC) curve analysis, the combining area under the ROC curve (AUC) of these five miRNAs was 0.636 [95% confidence interval (CI): 0.58-0.90]. MiRNA target gene prediction and functional annotation analysis showed that there was a significant enrichment in several pathways associated with nervous system and brain functions, supporting the hypothesis that differentially-regulated miRNAs may be involved in mechanism underlying development of MDD. We conclude that altered expression of miRNAs in PMBCs might be involved in multiple stages of MDD pathogenesis, and thus might be able to serve as specific biomarker for diagnosis of MDD.

A preliminary analysis of association between the down-regulation of microRNA-181b expression and symptomatology improvement in schizophrenia patients before and after antipsychotic treatment.

Despite the growing evidences on the relation of altered expression of miRNAs and schizophrenia, most schizophrenia subjects have an extensive antipsychotic treatment history and the pharmacological effects on miRNA expression are largely unknown. This study aimed to investigate the change of plasma microRNA-181b level and improvement of symptomatology before and after six-week antipsychotic treatment in schizophrenia patients, and explore their association. A total of 20 schizophrenia patients absent of antipsychotics and 20 age-and gender-matched normal controls were enrolled, and tested for 9 schizophrenia-associated microRNA (miR-30e, miR-34a, miR-181b, miR-195, miR-346, miR-432, miR-7, miR-132 and miR-212) expression levels in plasma using quantitative RT-PCR and for symptomatology improvement using Positive And Negative Syndrome Scale (PANSS) before and after treatment (olanzapine, quetiapine, ziprasidone and risperidone) for the patients only. Compared with the normal control group, the expression levels of miRNA-181b, miRNA-30e, miRNA-34a and miRNA-7 of the patients group were significantly higher (p < 0.05). Compared with those before treatment in the patient group, the symptomatology scores were significantly lower (p < 0.001), and the expression level of microRNA-181b was significantly down-regulated after treatment (p < 0.05). The change of miRNA-181b expression was positively correlated with the improvement of negative symptoms and lack of response symptoms (r = 0.502 and 0.557, P < 0.05, accounting for 20.2% and 26.4% respectively), and their therapeutic effects with OR being 11.283 and 5.119 respectively. We conclude that miRNA-181b, miRNA-30e, miRNA-34a and miRNA-7 are probably involved in pathogenesis of SZ, and the significant down-regulation of miRNA-181b expression predicts improvement of negative symptoms to treatment, and thus can serve as a potential plasmamolecular marker for antipsychotic responses.

A preliminary analysis of association betweenplasma microRNA expression alteration andsymptomatology improvement in Major DepressiveDisorder (MDD) patients before andafter antidepressant treatment

Background and Objectives: Currently, there is a serious need to find practical biomarker(s) for Major Depressive Disorder (MDD) therapeutic target(s). This study aimed to investigate the association between microRNA (miRNA, miR) expression level in Peripheral Blood Mononuclear Cells (PBMCs) and symptomatology improvement in MDD patients before and after six-week antidepressant treatment. Methods: By using an Affymetrix array that covers 723 human miRNAs, 26 miRNAs were identified with significantly altered expression in PBMCs in MDD patients, of which10 miRNAs were selected for quantitative real-time Reverse Transcription Polymerase Chain Reaction (RT-PCR) study. Twenty out of all the 81 MDD patients were selected formiRNA expression levels testing and symptomatology assessments before and after sixweektreatment. Results: Compared with the control group, the expression levels of miR-26b, miR-4743, miR-4498, miR-4485 and miR-1972 of the MDD group were significantly higher(P < 0.05); the changes of expression levels of miR-4743, miR-4498, miR-4485 and miR-1972 were positively related to retardation improvement (P < 0.05), and the change of expression level of miR-26b negatively to the improvement of day and night change(P < 0.05); regression analysis result demonstrated that the alteration of miR-4485 expression accounted for 28.8% of retardation improvement (P < 0.05). Conclusions: These five miRNAs (miR-4743, miR-4498, miR-4485, miR-1972 andmiR-26b) may serve as biomarker for MDD diagnosis and therapeutic targets for MDDtreatment (AU)