RESUMO
Manihot esculenta (cassava) contains two cyanogenic glucosides, linamarin and lotaustralin, biosynthesized from l-valine and l-isoleucine, respectively. In this study, cDNAs encoding two uridine diphosphate glycosyltransferase (UGT) paralogs, assigned the names UGT85K4 and UGT85K5, have been isolated from cassava. The paralogs display 96% amino acid identity, and belong to a family containing cyanogenic glucoside-specific UGTs from Sorghum bicolor and Prunus dulcis. Recombinant UGT85K4 and UGT85K5 produced in Escherichia coli were able to glucosylate acetone cyanohydrin and 2-hydroxy-2-methylbutyronitrile, forming linamarin and lotaustralin. UGT85K4 and UGT85K5 show broad in vitro substrate specificity, as documented by their ability to glucosylate other hydroxynitriles, some flavonoids and simple alcohols. Immunolocalization studies indicated that UGT85K4 and UGT85K5 co-occur with CYP79D1/D2 and CYP71E7 paralogs, which catalyze earlier steps in cyanogenic glucoside synthesis in cassava. These enzymes are all found in mesophyll and xylem parenchyma cells in the first unfolded cassava leaf. In situ PCR showed that UGT85K4 and UGT85K5 are co-expressed with CYP79D1 and both CYP71E7 paralogs in the cortex, xylem and phloem parenchyma, and in specific cells in the endodermis of the petiole of the first unfolded leaf. Based on the data obtained, UGT85K4 and UGT85K5 are concluded to be the UGTs catalyzing in planta synthesis of cyanogenic glucosides. The localization of the biosynthetic enzymes suggests that cyanogenic glucosides may play a role in both defense reactions and in fine-tuning nitrogen assimilation in cassava.
Assuntos
Glucosídeos/metabolismo , Glucosiltransferases/metabolismo , Manihot/enzimologia , Nitrilas/metabolismo , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos , Biocatálise , DNA Complementar/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Glucosídeos/química , Glucosiltransferases/genética , Glucosiltransferases/isolamento & purificação , Cinética , Manihot/genética , Manihot/metabolismo , Dados de Sequência Molecular , Nitrilas/química , Filogenia , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação , Coelhos , Proteínas Recombinantes , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade por SubstratoRESUMO
The ISB Cancer Genomics Cloud (ISB-CGC) is one of three pilot projects funded by the National Cancer Institute to explore new approaches to computing on large cancer datasets in a cloud environment. With a focus on Data as a Service, the ISB-CGC offers multiple avenues for accessing and analyzing The Cancer Genome Atlas, TARGET, and other important references such as GENCODE and COSMIC using the Google Cloud Platform. The open approach allows researchers to choose approaches best suited to the task at hand: from analyzing terabytes of data using complex workflows to developing new analysis methods in common languages such as Python, R, and SQL; to using an interactive web application to create synthetic patient cohorts and to explore the wealth of available genomic data. Links to resources and documentation can be found at www.isb-cgc.org Cancer Res; 77(21); e7-10. ©2017 AACR.
Assuntos
Computação em Nuvem , Biologia Computacional , Genômica , Neoplasias/genética , Conjuntos de Dados como Assunto , Genoma Humano , Humanos , Internet , National Cancer Institute (U.S.) , Pesquisa/tendências , Software , Estados UnidosRESUMO
Gene regulatory networks (GRNs) control embryonic development, and to understand this process in depth, researchers need to have a detailed understanding of both the network architecture and its dynamic evolution over time and space. Interactive visualization tools better enable researchers to conceptualize, understand, and share GRN models. BioTapestry is an established application designed to fill this role, and recent enhancements released in Versions 6 and 7 have targeted two major facets of the program. First, we introduced significant improvements for network drawing and automatic layout that have now made it much easier for the user to create larger, more organized network drawings. Second, we revised the program architecture so it could continue to support the current Java desktop Editor program, while introducing a new BioTapestry GRN Viewer that runs as a JavaScript web application in a browser. We have deployed a number of GRN models using this new web application. These improvements will ensure that BioTapestry remains viable as a research tool in the face of the continuing evolution of web technologies, and as our understanding of GRN models grows.
RESUMO
Gene and genome duplication is a key driving force in evolution of plant diversity. This has resulted in a number of large multi-gene families. Two of the largest multi-gene families in plants are the cytochromes P450 (P450s) and family 1 glycosyltransferases (UGTs). These two families are key players in evolution, especially of plant secondary metabolism, and in adaption to abiotic and biotic stress. In the model plant Arabidopsis thaliana there are 246 and 112 cytochromes P450 and UGTs, respectively. The Arabidopsis P450, cytochromes b(5), NADPH-cytochrome P450 reductases, and family 1 glycosyltransferases website (http://www.P450.kvl.dk) is a sequence repository of manually curated sequences, multiple sequence alignments, phylogenetic trees, sequence motif logos, 3D structures, intron-exon maps, and customized BLAST datasets.
Assuntos
Arabidopsis/genética , Sistema Enzimático do Citocromo P-450/genética , Citocromo-B(5) Redutase/genética , Citocromos b5/genética , Genes de Plantas , Glicosiltransferases/genética , Internet , Sequência de Aminoácidos , Arabidopsis/enzimologia , Sistema Enzimático do Citocromo P-450/química , DNA de Plantas , Evolução Molecular , Genoma de Planta , Dados de Sequência Molecular , Família Multigênica , Filogenia , Alinhamento de SequênciaRESUMO
Data mining methods have been used to identify 356 Cyt P450 genes and 99 related pseudogenes in the rice (Oryza sativa) genome using sequence information available from both the indica and japonica strains. Because neither of these genomes is completely available, some genes have been identified in only one strain, and 28 genes remain incomplete. Comparison of these rice genes with the 246 P450 genes and 26 pseudogenes in the Arabidopsis genome has indicated that most of the known plant P450 families existed before the monocot-dicot divergence that occurred approximately 200 million years ago. Comparative analysis of P450s in the Pinus expressed sequence tag collections has identified P450 families that predated the separation of gymnosperms and flowering plants. Complete mapping of all available plant P450s onto the Deep Green consensus plant phylogeny highlights certain lineage-specific families maintained (CYP80 in Ranunculales) and lineage-specific families lost (CYP92 in Arabidopsis) in the course of evolution.