As demonstrated in this study, the tomato F35H is capable of metaboliz ing liquiritigenin, although www.selleckchem.com/products/Gemcitabine-Hydrochloride(Gemzar).html to our knowledge liquiriti Inhibitors,Modulators,Libraries genin has never been found in tomato Inhibitors,Modulators,Libraries plants. Expression analysis showed that all the major genes of the flavonoid pathway tested, including F35H, had a clear increase in expression as a result of three days of nitrogen deprivation. Despite what seemed to be a general up regulation of the flavonoid pathway in this study, the growth conditions applied had not resulted in accumulation of anthocyanins at the time of sampling. At the time of sampling, the increase in gene expression was more prominent than the increase in level of rutin and kaempferol 3 rutinoside. As gene expression increases prior to accumulation of product this implies that accumulation of rutin and kaempferol 3 rutinoside had not yet reached the maximum.
Similar studies conducted on nitrogen deprived tomato plants have shown that Inhibitors,Modulators,Libraries also anthocya nins will appear over time. Possibly the concentrations of dihydrokaempferol and or dihydroquercetin have to exceed a threshold level for F35H to metabolise what FLS does not have capacity for. Similar studies showed far higher levels of flavonol derivatives than in the present study at the time of anthocyanin accumula tion, which might indicate that FLS does not have the capacity to metabolise all the dihydrokaempferol dihy droquercetin as the flow through the pathway escalates. The increase in transcripts of F3H in all Inhibitors,Modulators,Libraries parts of the nitrogen deprived plants, indicates increased production of the F3H enzyme, which hydroxylates dihydrokaemp ferol to dihydroquercetin.
The action of this enzyme. might explain why the content of rutin is much higher than kaempferol 3 rutinoside, since they have dihydroquercetin and dihydrokaempferol as precursors respectively. It should be mentioned that although the F3H tested here was a clear orthologue to the petunia F3H, the tomato Inhibitors,Modulators,Libraries F3H has not yet been cloned and characterised, hence its function still needs to be established. This is especially relevant considering that the F35H present in tomato is also capable of cata lysing the 3 hydroxylation. A similar study showed accumulation of antho cyanins in leaves of nitrogen deprived tomato plants. In this study the nitrogen deprivation lasted a minimum of four days, and flavonoid content continued to increase from the fourth to the eighth day of nitrogen deprivation. Consistent with the increase in rutin and kaempferol 3 rutinoside, the enzyme responsible for increasing flux into the phenylpropanoid pathway, PAL5 increased in expression as a response to nitrogen deprivation. KPT-330 1393477-72-9 The MYB type transcription factor ANT1, and the putative bHLH transcription factor SlJAF13, also increased in all parts of nitrogen deprived plants.