TY  - THES
AB  - In contrast to many other plants where biosynthesis of flavonoids and regulation of the involved genes is well analyzed, only little is known in the cultured apple M. x domestica about this pathway. Although most important intermediates and their structural genes are identified, regulation and the involved transcription factors are almost completely unknown.
In this work, four regulators of the flavonoid biosynthesis in M. x domestica were isolated and further analyzed.
Two of them were MdMYB9 and MdMYB11, both belonging to the group of MYB transcription factors and showing high similarity to proanthocyanidin-specific regulators from other plants. Both proteins were able to interact with co-factors and showed activation capabilities regarding promoters of putative A. thaliana target gene homologues in vivo.
Another analyzed protein was MdMYB10, which showed the highest similarity to known regulators specific for anthocyanin accumulation. MdMYB10 was also able to activate target genes while interacting with co-factors. Additionally, MdMYB10 could induce anthocyanin accumulation in A. thaliana pap1 knock-out mutants.
A fourth investigated factor, MdTTG1 belonged to the group of WD-repeat proteins.MdTTG1 showed interaction with bHLH and MYB co-factors, leading to the assumption, that the same MBW complex known from other plants is also present in M. x domestica.
Furthermore, in this work could be shown that MdTTG1 was able to functionally complement A. thaliana ttg1 knock-out plants in all known phenotypes.
In fruit material of M. x domestica, expression of selected structural genes, acitivity of the encoded enzymes and accumulation of metabolites could be shown to be correlated in two different years. Expression, enzyme activity and metabolite accumulation were found to be highest in early fruit developmental stages while during fruit ripening, measured values for each parameter decreased.
DA  - 2010
LA  - ger
PY  - 2010
TI  - Untersuchungen zur Regulation der Flavonoidbiosynthese im Kulturapfel Malus x domestica
UR  - https://nbn-resolving.org/urn:nbn:de:hbz:361-18476
Y2  - 2024-11-22T05:49:03
ER  -