LaPT2 Gene Encodes a Flavonoid Prenyltransferase in White Lupin

Legume plants are rich in prenylated flavonoid compounds, which play an important role in plant defense and human health. In the present study, we identified a prenyltransferase (PT) gene, named LaPT2, in white lupin (Lupinus albus), which shows a high identity and close relationship with the other known PT genes involved in flavonoid prenylation in planta. The recombinant LaPT2 protein expressed in yeast cells exhibited a relatively strong activity toward several flavonols (e.g., kaempferol, quercetin, and myricetin) and a relatively weak activity toward flavanone (naringenin). In addition, the recombinant LaPT2 protein was also active toward several other types of flavonoids, including galangin, morin, 5-deoxyquercetin, 4'-O-methylkaempferol, taxifolin, and aromadendrin, with distinct enzymatic affinities. The LaPT2 gene was preferentially expressed in the roots, which is consistent with the presence of prenylated flavonoid kaempferol in the roots. Moreover, we found that the expression level of LaPT2 paralleled with those of LaF3H1 and LaFLS2 genes that were relatively higher in roots and lower in leaves, suggesting that they were essential for the accumulation of prenylated flavonoid kaempferol in roots. The deduced full-length LaPT2 protein and its signal peptide fused with a green fluorescent protein (GFP) are targeted to plastids in the Arabidopsis thaliana protoplast. Our study demonstrated that LaPT2 from white lupin is responsible for the biosynthesis of prenylated flavonoids, in particular flavonols, which could be utilized as phytoalexin for plant defense and bioactive flavonoid compounds for human health

Identification of Transcription Factor Genes and Functional Characterization of PlMYB1 From Pueraria lobata

Kudzu, Pueraria lobata, is a traditional Chinese food and medicinal herb that has been commonly used since ancient times. Kudzu roots are rich sources of isoflavonoids, e.g., puerarin, with beneficial effects on human health. To gain global information on the isoflavonoid biosynthetic regulation network in kudzu, de novo transcriptome sequencings were performed using two genotypes of kudzu with and without puerarin accumulation in roots. RNAseq data showed that the genes of the isoflavonoid biosynthetic pathway were significantly represented in the upregulated genes in the kudzu with puerarin. To discover regulatory genes, 105, 112, and 143 genes encoding MYB, bHLH, and WD40 transcription regulators were identified and classified, respectively. Among them, three MYB, four bHLHs, and one WD40 gene were found to be highly identical to their orthologs involved in flavonoid biosynthesis in other plants. Notably, the expression profiles of PlMYB1, PlHLH3-4, and PlWD40-1 genes were closely correlated with isoflavonoid accumulation profiles in different tissues and cell cultures of kudzu. Over-expression of PlMYB1 in Arabidopsis thaliana significantly increased the accumulation of anthocyanins in leaves and proanthocyanidins in seeds, by activating AtDFR, AtANR, and AtANS genes. Our study provided valuable comparative transcriptome information for further identification of regulatory or structural genes involved in the isoflavonoid pathway in P. lobata, as well as for bioengineering of bioactive isoflavonoid compounds

Genome-Wide Identification and Analyses of Drought/Salt-Responsive Cytochrome P450 Genes in Medicago truncatula

Cytochrome P450 monooxygenases (P450s) catalyze a great number of biochemical reactions and play vital roles in plant growth, development and secondary metabolism. As yet, the genome-scale investigation on P450s is still lacking in the model legume Medicago truncatula. In particular, whether and how many MtP450s are involved in drought and salt stresses for Medicago growth, development and yield remain unclear. In this study, a total of 346 MtP450 genes were identified and classified into 10 clans containing 48 families. Among them, sixty-one MtP450 genes pairs are tandem duplication events and 10 MtP450 genes are segmental duplication events. MtP450 genes within one family exhibit high conservation and specificity in intron-exon structure. Meanwhile, many Mt450 genes displayed tissue-specific expression pattern in various tissues. Specifically, the expression pattern of 204 Mt450 genes under drought/NaCl treatments were analyzed by using the weighted correlation network analysis (WGCNA). Among them, eight genes (CYP72A59v1, CYP74B4, CYP71AU56, CYP81E9, CYP71A31, CYP704G6, CYP76Y14, and CYP78A126), and six genes (CYP83D3, CYP76F70, CYP72A66, CYP76E1, CYP74C12, and CYP94A52) were found to be hub genes under drought/NaCl treatments, respectively. The expression levels of these selected hub genes could be induced, respectively, by drought/NaCl treatments, as validated by qPCR analyses, and most of these genes are involved in the secondary metabolism and fatty acid pathways. The genome-wide identification and co-expression analyses of M. truncatula P450 superfamily genes established a gene atlas for a deep and systematic investigation of P450 genes in M. truncatula, and the selected drought-/salt-responsive genes could be utilized for further functional characterization and molecular breeding for resistance in legume crops

Up-regulation of ceRNA TINCR by SP1 contributes to tumorigenesis in breast cancer

Abstract Background Assembling evidences suggested that aberrant expression of tissue differentiation-inducing non-protein coding RNA (TINCR) intimately associated with variety of human cancer. However, the expression pattern and involvement of TINCR in breast cancer has not been fully investigated. Here we set out to analyze expression of TINCR in breast cancer and elucidate its mechanistic involvement in tumor incidence and progression. Methods The expression of TINCR was determined by q-PCR. SP1 binding sites were analyzed by ChIP-qPCR. The relative transcription activity was measured with luciferase reporter assay. Cell viability was measured with CCK-8 method. Clonogenic capacity was evaluated by soft agar assay. Cell apoptosis was analyzed by Annexin V/7-AAD staining. The migration and invasion were determined by trans-well assay and wound healing. The tumor growth in vivo was evaluated in xenograft mice model. Protein expression was quantified by immunoblotting. Results TINCR was aberrantly up-regulated by SP1, which in turn stimulated cell proliferation, anchorage-independent growth and suppressed cell apoptosis in breast cancer. TINCR silencing significantly suppressed migration and invasion in vitro and xenograft tumor growth in vivo. Mechanistically, TINCR modulated KLF4 expression via competing with miR-7, which consequently contributed to its oncogenic potential. MiR-7 inhibition severely compromised TINCR silencing-elicited tumor repressive effects. Conclusion Our data uncovered a crucial role of TINCR-miR-7-KLF4 axis in human breast cancer

GbMYBR1fromGinkgo bilobarepresses phenylpropanoid biosynthesis and trichome development inArabidopsis

Main Conclusion GbMYBR1, a new type of R2R3-MYB repressor fromGinkgo biloba, displayed pleiotropic effects on plant growth, phenylpropanoid accumulation, by regulating multiple related genes at different levels. Ginkgo bilobais a typical gymnosperm that has been thriving on earth for millions of years. MYB transcription factors (TFs) play important roles in diverse processes in plants. However, the role of MYBs remains largely unknown inGinkgo. Here, an MYB TF gene fromGinkgo, designated asGbMYBR1, was found to act as a repressor in multiple processes.GbMYBR1was mainly expressed in the leaves ofGinkgo.Over-expression ofGbMYBR1inArabidopsis thalianaled to growth retardation, decreases in lignin content, reduced trichome density, and remarkable reduction in anthocyanin and flavonol contents in leaves.Proanthocyanidin content was decreased in the seeds of transgenicArabidopsis, which led to light-brown seed color. Both qPCR and transcriptome sequencing analyses demonstrated that the transcript levels of multiple genes related to phenylpropanoid biosynthesis, trichome formation, and pathogen resistance were down-regulated in the transgenicArabidopsis.In particular, we found that GbMYBR1 directly interacts with the bHLH cofactor GL3 as revealed by yeast two-hybrid assays. Our work indicated thatGbMYBR1has pleiotropic effects on plant growth, phenylpropanoid accumulation, and trichome development, mediated by interaction with GL3 or direct suppression of key pathway genes. Thus,GbMYBR1represents a novel type of R2R3 MYB repressor

LaPT2 Gene Encodes a Flavonoid Prenyltransferase in White Lupin

Legume plants are rich in prenylated flavonoid compounds, which play an important role in plant defense and human health. In the present study, we identified a prenyltransferase (PT) gene, named LaPT2, in white lupin (Lupinus albus), which shows a high identity and close relationship with the other known PT genes involved in flavonoid prenylation in planta. The recombinant LaPT2 protein expressed in yeast cells exhibited a relatively strong activity toward several flavonols (e.g., kaempferol, quercetin, and myricetin) and a relatively weak activity toward flavanone (naringenin). In addition, the recombinant LaPT2 protein was also active toward several other types of flavonoids, including galangin, morin, 5-deoxyquercetin, 4'-O-methylkaempferol, taxifolin, and aromadendrin, with distinct enzymatic affinities. The LaPT2 gene was preferentially expressed in the roots, which is consistent with the presence of prenylated flavonoid kaempferol in the roots. Moreover, we found that the expression level of LaPT2 paralleled with those of LaF3H1 and LaFLS2 genes that were relatively higher in roots and lower in leaves, suggesting that they were essential for the accumulation of prenylated flavonoid kaempferol in roots. The deduced full-length LaPT2 protein and its signal peptide fused with a green fluorescent protein (GFP) are targeted to plastids in the Arabidopsis thaliana protoplast. Our study demonstrated that LaPT2 from white lupin is responsible for the biosynthesis of prenylated flavonoids, in particular flavonols, which could be utilized as phytoalexin for plant defense and bioactive flavonoid compounds for human health

Genistein-Specific G6DT Gene for the Inducible Production of Wighteone in Lotus japonicus

Prenylated isoflavonoids have been found in several legume plants, and they possess various biological activities that play important roles in both plant defense and human health. However, it is still unknown whether prenylated isoflavonoids are present in the model legume plant Lotus japonicus. In the present study, we found that the prenylated isoflavonoid wighteone was produced in L. japonicus when leaf was supplemented with genistein. Furthermore, a novel prenyltransferase gene, LjG6DT, was identified, which shared high similarity with and was closely related to several known prenyltransferase genes involved in isoflavonoid biosynthesis. The recombinant LjG6DT protein expressed in yeast exhibited prenylation activity toward genistein as an exclusive substrate, which produced wighteone, a prenylated genistein at the C-6 position that occurs normally in legume plants. The LjG6DT-green fluorescent protein (GFP) fusion protein is targeted to plastids. The transcript level of LjG6DT is induced by glutathione, methyl jasmonate and salicylic acid, implying that LjG6DT is involved in stress response. Overexpression of LjG6DT in L. japonicus hairy roots led to increased accumulation of wighteone when genistein was supplied, indicating that LjG6DT is functional in vivo. Feeding assays with the upstream intermediate naringenin revealed that accumulation of wighteone in L. japonicus was dependent on genistein supplementation, and accumulation of wighteone is competed by genistein methylation. This study demonstrated that phytoalexin wighteone is inducibly produced in L. japonicus, and it provides new insight into the biosynthesis and accumulation of prenylated isoflavonoids in legume plants

Additional file 1: of Up-regulation of ceRNA TINCR by SP1 contributes to tumorigenesis in breast cancer

Figure S1 TINCR predominantly located in cytoplasm. Subcellular localization of TINCR was analyzed RNA hybridization with the specific Stellaris RNA FISH probes followed by confocal microscope imaging. TINCR was detected in red channel, while cytoplasmic GAPDH transcript was detected in green channel. The nuclei were counter-stained with DAPI. (JPEG 29 kb

Metagenomic assembly unravel microbial response to redox fluctuation in acid sulfate soil

Acid sulfate soil (ASS) is sensitive to redox fluctuations induced by climate change and human activities. Oxidation of sulfur and sulfide in ASS leads to the release of acid and consequently metals, posing severe hazards to coastal environment, while microbial contribution and response to oxidation is poorly understood. Here we used metagenomic sequencing to delineate the shift in microbial community structures and functional genes in ASS upon exposure to aerobic conditions. Aerobic incubation resulted in significant shifts in microbial communities in both topsoil and parent material. Archaea decreased significantly in the parent material after aerobic incubation. The relative abundance of sulfur cycling genes in the parent material layer was significantly higher than those in the topsoil, and multiple sulfide oxidation genes increased after aerobic oxidation. Metagenomic assembly enabled construction of eight key draft genomes from ASS. Three of them (GS3, GS6 and GT3) are novel strains of Thermoplasmatales, Acidothermales (Acidothermus) and Acidimicrobiales, respectively. Functional gene annotation of these population genomes revealed a dominance of sulfur cycling genes and acid tolerant genes. These findings highlight the microbial response to environmental change and identify the ecological adaptation and survival strategies of microbial communities in acid sulfate soils