02455nam a2200253 a 450000100080000000500110000800800410001910000230006024501050008326001570018850000080034552016250035365000230197865000160200165000190201765000090203670000280204570000180207370000190209170000290211070000210213970000220216070000190218216556302023-07-10       2008    bl uuuu     u00u1 u    #d1 aFREITAS-ASTÚA, F.  aPutative novel genes involved in the biosynthesis of sweet orange flavonoids.h[electronic resource]  aIn: THE INTERNATIONAL CONFERENCE ON THE STATUS OF PLANT & ANIMAL GENOME RESEARCH, 16., 2008, San Diego. Final abstracts guide. San Diego: Illuminac2008  aP19  aFlavonoids constitute a major group of secondary metabolites and play important roles in the development, reproduction, defense, and pigmentation of plants. Flavones represent one of the most abundant and important classes of flavonoids, occurring in almost all plant tissues. The formation of flavones is catalyzed by either flavone synthase I or flavone synthase II (FNSII). Both enzymes enable the control of a biosynthetic step at an important junction of this pathway leading not only to flavones but also to various flavonoid classes, as isoflavones, flavonols, flavanols, and anthocyanins. Flavonols are important co-pigments that may affect the shade of the color in flowers and fruits. One of the main enzymes in the flavonol biosynthesis pathway is flavanone-3-hydroxylase (F3H), which follows chalcone isomerase in the pathway and hydroxylates flavanones at the 3´ position to form dihydroflavonols. Analyses of the Citrus EST (CitEST) database revealed the presence of putative novel fnsII and f3h genes involved in the synthesis of flavones and flavonols, respectively, in Citrus sinensis. Even though flavones have been found in several species and varieties within the Citrus genus, this is the first study to report the presence of two copies of the fnsII gene in sweet orange. Moreover, in addition to the available Citf3h gene sequence, we identified another f3h transcript in C. sinensis. Here we report the in silico characterization of such genes expression patterns in different citrus tissues and fruit developmental stages, and provide phylogenetic analyses of their deduced amino acid sequences  aComposto Fenólico  aFlavonóide  aFruta Cítrica  aGene1 aSILVA-PINHATI, A. C. O.1 aBERGER, I. J.1 aLUCHETA, A. R.1 aBASÍLIO-PALMIERI, A. C.1 aAMARAL, A. M. do1 aBARBOSA, A. V. G.1 aMACHADO, M. A.