Tailoring tropane alkaloid accumulation in transgenic hairy roots of Atropa baetica by over-expressing the gene encoding hyoscyamine 6beta-hydroxylase.
Atropa baetica hairy roots, over-expressing cDNA from Hyoscyamus niger encoding the gene for hyoscyamine 6beta-hydroxylase (H6H), were produced by Agrobacterium rhizogenes infection. The transgenic roots over-expressing h6h had an altered alkaloid profile in which hyoscyamine was entirely converted into scopolamine. In the best h6h clone, scopolamine accumulation increased 9-fold compared to plants, amounting to 5.6 mg g dry wt(-1), some of which was released into the liquid medium. Only negligible amounts of hyoscyamine were detected. In contrast, the gus control culture contained a much higher amount of hyoscyamine than scopolamine, mimicking the situation in the plant. At the molecular level, a higher conversion of hyoscyamine into scopolamine was related to a higher level of h6h mRNA; in some instances this was 5 - 10-fold higher.
Zárate
Rafael
R
Instituto Universitario de Bio-Orgánica A.G. González, Universidad de La Laguna, Ave. Francisco Sánchez 2, 38206 La Laguna, Tenerife, Spain. rzarate@ull.es
el Jaber-Vazdekis
Nabil
N
Medina
Braulio
B
Ravelo
Angel G
AG
D000470:Alkaloids / Q000737:chemistry; D032282:Atropa; D001709:Biotechnology / Q000379:methods*; D003470:Culture Media; D018076:DNA, Complementary / Q000378:metabolism; D017343:Genes, Plant; D005818:Genetic Engineering; D006899:Mixed Function Oxygenases / Q000235:genetics* / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism; D018517:Plant Roots; D030821:Plants, Genetically Modified; D010957:Plasmids / Q000378:metabolism; D012313:RNA / Q000378:metabolism
D000470:Alkaloids; D003470:Culture Media; D018076:DNA, Complementary; D010940:Plant Proteins; D012313:RNA; D006899:Mixed Function Oxygenases; C052273:hyoscyamine (6S)-dioxygenase