Background Cynara cardunculus L. is an allogamous spe cies native to the Mediterranean basin, belonging to the family selleck catalog Asteraceae, order Asterales. The species includes three subspecies the globe artichoke, which is grown Inhibitors,Modulators,Libraries for its edible immature inflorescence. the cultivated cardoon, which produces fleshy stalks. and Inhibitors,Modulators,Libraries their common ancestor, the wild car doon Fiori. Leaf extracts con tain molecules of some pharmaceutical interest, including antibacterial antioxidative anti HIV, hepatoprotective, choleretic, cholesterol biosynthesis inhibitory and anticancer activities. Many of these properties rely on specific phenylpropanoids, particularly 5 caffeoylquinic acid and di caffeoylquinic acids, along with various fla vonoid compounds.
The level and composition of the PP pool can vary considerably between organisms, tis sues, developmental stages and in response to environ mental conditions. PP metabolism is induced by biotic and abiotic stresses such as wounding, UV irradia tion and pathogen attack. Recently, Moglia et al. have established Inhibitors,Modulators,Libraries that UV C radiation enhances the level of caffeoylquinic acid in the globe artichoke. The CGA biosynthesis pathway has been the target of some detailed research, mainly focused among Solanaceae Inhibitors,Modulators,Libraries species. Even though little direct information is as yet available concerning the bio synthesis of di and tri caffeoylquinic acid, the prior accu mulation of CGA does appear to be necessary. Three distinct pathways have been proposed for the synthesis of CGA the trans esterification of caffeoyl CoA and quinic acid via hydroxycinnamoyl CoA quinate hydroxy cinnamoyl transferase activity.
the hydroxylation of p coumaroyl quinate to CGA. and the hydroxylation of p coumaroyl shikimate to caffe oyl shikimic acid, which is then converted to caffeoyl CoA, a substrate of hydroxycinnamoyl CoA shikimate hydroxycinnamoyl Inhibitors,Modulators,Libraries transferase HCT. The silencing of the HQT gene in tobacco and tomato results in a 98% reduction in CGA level, but does not affect lignin forma tion, so in these species at least, the first two of these routes are probably responsible for the biosynthesis and accumulation of CGA. On the other hand, a lowered HCT expression in tobacco, Pinus radiata and Medicago sativa changes lignin amount and composi tion, thereby implicating the third pathway in lignin bio synthesis.
A fourth route, which EPZ5676 uses caffeoyl glucoside as the active intermediate, has been described in sweet potato. Although the globe artichoke HCT sequence is similar to that of tobacco HCT, its activity is more closely related to that of tobacco and tomato HQT, in showing a preference for quinic over shikimic acid as acceptor. Linkage maps, created for genes in biosynthetic pathways in several species, can be used to locate known genes of a pathway within a specific genomic region. The presence of allelic variation at the sequence level in genes of known biochemical functional is useful for candidate gene approaches.