naa a22 4500 51073040X CHVBK 20180411082950.0 cr unu---uuuuu 180411e20131201xx s 000 0 eng 10.1007/s11295-013-0653-5 doi (NATIONALLICENCE)springer-10.1007/s11295-013-0653-5 Identification of lipoxygenase (LOX) genes putatively involved in fruit flavour formation in apple ( Malus × domestica ) [Elektronische Daten] [Jörg Vogt, Doreen Schiller, Detlef Ulrich, Wilfried Schwab, Frank Dunemann] Lipoxygenases (LOXs) are non-heme iron-containing enzymes that catalyse the dioxygenation of polyunsaturated fatty acids. The resulting hydroperoxides are further metabolized into biologically active oxylipins including jasmonic acid and green leaf volatiles (GLV) such as C6-aldehydes and C6-alcohols. LOXs are also known to play a decisive role in the production of volatiles that influence the flavour and aroma of fruits and vegetables. To obtain an overview of the inventory of the apple LOX gene family, the published Golden Delicious genome was mined for LOX coding sequences. In total, 23 putative functional LOX genes were identified and used for the construction of a phylogenetic tree. Two sub-trees were found which differentiate the LOX sequences into type 1- and type 2-LOXs. Their chromosomal locations were assigned to the predicted chromosomes of the assembled Golden Delicious genome sequence. Single LOX genes as well as clusters consisting of up to four genes were detected on apple chromosomes 2, 4, 5, 6, 7, 9, 11, 12, 13 and 16. LOX gene clusters on chromosomes 2 and 7, and on 4 and 12, respectively, indicated duplicated genome regions with high homology, which supports previous hypotheses of an ancient genome-wide duplication event in Malus. By using a PCR-based strategy, eight genes belonging to both type 1- and type 2-LOXs with altogether 30 full-length sequences were cloned. Several putative LOX alleles were detected within the same and among different apple cultivars. Two parental genetic maps available for ‘Discovery' and ‘Prima' were used for a quantitative trait locus (QTL) mapping experiment of apple volatile compounds known to be produced by the LOX biosynthetic pathway. The QTL detection resulted in a total number of 15 QTLs for eight volatiles (esters and the aldehyde hexanal) which were located on chromosomes 2, 7, 9 and 12 determined in silico as carriers of at least one LOX gene. To examine the putative roles of apple LOX genes in fruit volatile production, the spatial and temporal expression patterns were analysed by RT-PCR-based transcription analyses of apple leaf and fruit tissues. Two genes, MdLOX1a and MdLOX5e, were identified as candidate genes to be involved in fruit aroma volatile production in apple. The genetic association of QTLs found for the GLV hexanal at the top of chromosome 7, three clustered MdLOX5 genes with a putative 13-LOX function and published apple aphid resistance factors located all in the same region of chromosome 7 indicate that a lipoxygenase action might be involved in Malus aphid resistance reactions. Springer-Verlag Berlin Heidelberg, 2013 Green leaf volatile nationallicence Aldehyde nationallicence Ester nationallicence Gene family nationallicence Candidate gene nationallicence Gene expression nationallicence Vogt Jörg Institute for Breeding Research on Horticultural and Fruit Crops, Julius Kühn Institute (JKI), Pillnitzer Platz 3a, 01326, Dresden, Germany aut Schiller Doreen Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354, Freising, Germany aut Ulrich Detlef Institute for Ecological Chemistry, Plant Analysis and Stored Product Protection, Julius Kühn Institute (JKI), Erwin-Baur-Str. 27, 06484, Quedlinburg, Germany aut Schwab Wilfried Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354, Freising, Germany aut Dunemann Frank Institute for Breeding Research on Horticultural and Fruit Crops, Julius Kühn Institute (JKI), Erwin-Baur-Str. 27, 06484, Quedlinburg, Germany aut Tree Genetics & Genomes Springer Berlin Heidelberg 9/6(2013-12-01), 1493-1511 1614-2942 9:6<1493 2013 9 11295 https://doi.org/10.1007/s11295-013-0653-5 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11295-013-0653-5 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Vogt Jörg Institute for Breeding Research on Horticultural and Fruit Crops, Julius Kühn Institute (JKI), Pillnitzer Platz 3a, 01326, Dresden, Germany aut NATIONALLICENCE 700 1- Schiller Doreen Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354, Freising, Germany aut NATIONALLICENCE 700 1- Ulrich Detlef Institute for Ecological Chemistry, Plant Analysis and Stored Product Protection, Julius Kühn Institute (JKI), Erwin-Baur-Str. 27, 06484, Quedlinburg, Germany aut NATIONALLICENCE 700 1- Schwab Wilfried Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354, Freising, Germany aut NATIONALLICENCE 700 1- Dunemann Frank Institute for Breeding Research on Horticultural and Fruit Crops, Julius Kühn Institute (JKI), Erwin-Baur-Str. 27, 06484, Quedlinburg, Germany aut NATIONALLICENCE 773 0- Tree Genetics & Genomes Springer Berlin Heidelberg 9/6(2013-12-01), 1493-1511 1614-2942 9:6<1493 2013 9 11295 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer