What caught the eye was the 4-methylumbelliferyl moiety, above. Regarding nodulation in plants, Stafford was on it:
'Subsequent work indicated that apigenin and luteolin, nod-induceres and strong chemoattractants, are recognized by a common receptor, but that there is an additional separate receptor for luteolin alone. Naringenin produced only a low response. Umbelliferone (a coumarin) and acetosyringone (lignin product) alsor produced strong chemotactic responses. A study of three regulatory nodD alleles in Rhizobium meliloti indicated that all three nod D copies have a common nod-promoter activating ability, but evolutionarily diverged flavonoid-recognizing abilities.'
....
Photoregulated Pathways
Three photoceptors have now been implicated in the regulation of flavonoid metabolism: the phytochrome R/FR system, the blue/UV-A light photoreceptor (cryptochrome, possibly a flavoprotein), and an unidentified UV-B receptor. (UV-A is a long wavelength UV between 320 and 400nm, whereas UV-B is a shorter wavelength between 280 and 320nm). All three photoreceptors are involved in flavonoid synthesis in cell suspension cultures of parsley (Petroselinum hortense) and in Sorghum seedlings....A synergistic effect in in anthocyanin biosynthesis that involved UV-B, red light, and an unidentified photosynthetic product was reported in apple fruit.'
(Stafford, Flavonoid Metabolism)
The important passage that links various skin cancers to the Australian Aboriginal tree, Codonocarpus, for Brassicaceae glucosinolates (and branched-chain amino acids) mentioned in this thread, as well as its use against cancers of the tongue, follows. Notice that the lower epidermis in plants is the basal cell carcinoma zone in humans:
'The effect of phytochrome on the two pathways leading to quercetin and to anthocyanin were compared in mustard seedlings (Sinapis alba). The effect of cytochrome on the two end products and their enzymes was different in the two studies. In the case of Beggs, et al, the independently measured anthocyanin-associated PAL (phenylalanine ammonia lyase) of the lower epidermis where quercitin is accumulated. Anthocyanin formation preceded that of quercitin. Broedenfeldt and Mohr concluded that the operation of phytochrome was the same in both cases, but that the difference in responsiveness toward the 'stored phytochrome signal' made the difference. They found no close correlation between the activities of PAL and chalcone synthase and the rates of synthesis of the end products. Their assumption, however, that the rate of enzyme synthesis and turnover are the same in all cells involved may not be valid, especially since the two products are produced in different cells of the epidermis.'
(Stafford HA, op cit)
'Subsequent work indicated that apigenin and luteolin, nod-induceres and strong chemoattractants, are recognized by a common receptor, but that there is an additional separate receptor for luteolin alone. Naringenin produced only a low response. Umbelliferone (a coumarin) and acetosyringone (lignin product) alsor produced strong chemotactic responses. A study of three regulatory nodD alleles in Rhizobium meliloti indicated that all three nod D copies have a common nod-promoter activating ability, but evolutionarily diverged flavonoid-recognizing abilities.'
....
Photoregulated Pathways
Three photoceptors have now been implicated in the regulation of flavonoid metabolism: the phytochrome R/FR system, the blue/UV-A light photoreceptor (cryptochrome, possibly a flavoprotein), and an unidentified UV-B receptor. (UV-A is a long wavelength UV between 320 and 400nm, whereas UV-B is a shorter wavelength between 280 and 320nm). All three photoreceptors are involved in flavonoid synthesis in cell suspension cultures of parsley (Petroselinum hortense) and in Sorghum seedlings....A synergistic effect in in anthocyanin biosynthesis that involved UV-B, red light, and an unidentified photosynthetic product was reported in apple fruit.'
(Stafford, Flavonoid Metabolism)
The important passage that links various skin cancers to the Australian Aboriginal tree, Codonocarpus, for Brassicaceae glucosinolates (and branched-chain amino acids) mentioned in this thread, as well as its use against cancers of the tongue, follows. Notice that the lower epidermis in plants is the basal cell carcinoma zone in humans:
'The effect of phytochrome on the two pathways leading to quercetin and to anthocyanin were compared in mustard seedlings (Sinapis alba). The effect of cytochrome on the two end products and their enzymes was different in the two studies. In the case of Beggs, et al, the independently measured anthocyanin-associated PAL (phenylalanine ammonia lyase) of the lower epidermis where quercitin is accumulated. Anthocyanin formation preceded that of quercitin. Broedenfeldt and Mohr concluded that the operation of phytochrome was the same in both cases, but that the difference in responsiveness toward the 'stored phytochrome signal' made the difference. They found no close correlation between the activities of PAL and chalcone synthase and the rates of synthesis of the end products. Their assumption, however, that the rate of enzyme synthesis and turnover are the same in all cells involved may not be valid, especially since the two products are produced in different cells of the epidermis.'
(Stafford HA, op cit)
