Purple foliage always appears in Camellia sinensis families; however, the transcriptional regulation of anthocyanin biosynthesis is unknown. The tea bud sport cultivar ‘Zijuan’ confers an abnormal pattern of anthocyanin accumulation, resulting in a mutant phenotype that has a striking purple color in young foliage and in the stem. In this study, we aimed to unravel the underlying molecular mechanism of anthocyanin biosynthetic regulation in C. sinensis. Our results revealed that activation of the R2R3-MYB transcription factor (TF) anthocyanin1 (CsAN1) specifically upregulated the bHLH TF CsGL3 and anthocyanin late biosynthetic genes (LBGs) to confer ectopic accumulation of pigment in purple tea. We found CsAN1 interacts with bHLH TFs (CsGL3 and CsEGL3) and recruits a WD-repeat protein CsTTG1 to form the MYB-bHLH-WDR (MBW) complex that regulates anthocyanin accumulation. We determined that the hypomethylation of a CpG island in the CsAN1 promoter is associated with the purple phenotype. Furthermore, we demonstrated that low temperature and long illumination induced CsAN1 promoter demethylation, resulting in upregulated expression to promote anthocyanin accumulation in the foliage. The successful isolation of CsAN1 provides important information on the regulatory control of anthocyanin biosynthesis in C. sinensis and offers a genetic resource for the development of new varieties with enhanced anthocyanin content.

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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.

Plant biosynthesis involves numerous specialized metabolites with diverse chemical natures and biological activities. The biosynthesis of metabolites often exclusively occurs in response to tissue-specific combinatorial developmental cues that are controlled at the transcriptional level. Capsaicinoids are a group of specialized metabolites that confer a pungent flavor to pepper fruits. Capsaicinoid biosynthesis occurs in the fruit placenta and combines its developmental cues. Although the capsaicinoid biosynthetic pathway has been largely characterized, the regulatory mechanisms that control capsaicinoid metabolism have not been fully elucidated. In this study, we combined fruit placenta transcriptome data with weighted gene coexpression network analysis (WGCNA) to generate coexpression networks. A capsaicinoid-related gene module was identified in which the MYB transcription factor CaMYB48 plays a critical role in regulating capsaicinoid in pepper. Capsaicinoid biosynthetic gene (CBG) and CaMYB48 expression primarily occurs in the placenta and is consistent with capsaicinoid biosynthesis. CaMYB48 encodes a nucleus-localized protein that primarily functions as a transcriptional activator through its C-terminal activation motif. CaMYB48 regulates capsaicinoid biosynthesis by directly regulating the expression of CBGs, including AT3a and KasIa. Taken together, the results of this study indicate ways to generate robust networks optimized for the mining of CBG-related regulators, establishing a foundation for future research elucidating capsaicinoid regulation.

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Gastric cancer is a fatal disease and the availability of early diagnostic methods is limited. There is an urgent need to identify effective targets for early diagnosis and therapeutics. UbcH10 is a ubiquitin-conjugating enzyme with high expression in various types of cancers. In the present study, several gastric tumor cell lines with high or low expression of UbcH10 were exploited to study the role of UbcH10 in gastric cancer. Knockdown of UbcH10 expression using siRNA in gastric cancer cell lines with high expression of UbcH10 resulted in reduced proliferation, increased cisplatin-induced apoptosis and reduced serum-induced ERK, Akt and p38 phosphorylation signaling. In agreement, overexpression of UbcH10 in gastric cancer cell lines with low expression of UbcH10 led to enhanced cell proliferation and resistance to cisplatin-induced apoptosis. Most importantly, IHC analyses showed that the UbcH10 protein was expressed at a high level in most patient gastric cancer tissues, but was absent in adjacent mesenchyme tissues. These data suggest that UbcH10 may promote gastric cancer growth and can serve as a biomarker for diagnosis or as a target for novel therapeutics in gastric cancer.

Accumulating evidence has shown a critical role of long‐non‐coding RNAs (lncRNAs) during multiple tumor progression. However, the potential functions of LINC00504 in colon cancer as well as its mechanisms remain obscure. By lncRNA profiling, we identified LINC00504 as a novel oncogenic lncRNA in colon cancer. The lncRNA LINC00504 was markedly upregulated in colon cancer cell lines and specimens. LINC00504 increases viability and migration of colon cells in vitro. Furthermore, LINC00504 also enhances colon cancer xenograft tumors in vivo. We noted that LINC00504 regulates metabolism at a transcriptional level which influences multiple metabolic pathways, such as glucose metabolism, pentose phosphate pathway, and tricarboxylic acid cycle. Mechanistic study showed that LINC00504 could interact with c‐Myc to promote chromatin recruitment of c‐Myc and enhance its transactivation activity. Collectively, our results showed that LINC00504 serves as an important transcriptional regulator for c‐Myc in colon cancer cells. LINC00504 can reprogram central metabolism in colon cancer cells implying that LINC00504 may serve as a potential target for therapeutic intervention.

Marital status was found to be an independent prognostic factor for survival in various cancer types, but it hasn't been studied in gastric cancer. The Surveillance, Epidemiology and End Results database was used to compare survival outcomes with marital status. A total of 16,106 eligible patients were identified. Patients in the widowed group had the highest proportion of women, more common site of stomach, more prevalence of elderly patients, higher percentage of adenocarcinoma, and more tumors at localized stage (P < 0.05). Patients in married group had better 5year cause-specific survival (CSS) than those unmarried (P < 0.05). Further analysis showed that widowed patients always presented the lowest CSS compared with that of other groups. Widowed patients had 7.1% reduction in 5-year CSS compared with married patients at Localized stage (77.2% vs 70.1%, P < 0.001), 9.6% reduction at Regional stage (38.2% vs 28.6%, P < 0.001), and 4.7% reduction at Distant stage (13.3% vs 8.6%, P < 0.001). These results showed that unmarried patients were at greater risk of cancer specific mortality. Despite favorable clinicpathological characteristics, widowed patients were at highest risk of death compared with other groups.