The phloem mobility of glucosinolates
The phloem mobility of glucosinolates
复制标题
DOI：
10.1093/jexbot/50.335.745
复制
发表时间：
1999-06-01
影响因子：
6.9
通讯作者：
Baker, DA
中科院分区：
文献类型：
--
作者：
Brudenell, AJP;Griffiths, H;Baker, DA
硫代葡萄糖苷在甘蓝型油菜中的运输特性是有意义的，因为运输机制的鉴定可能导致在特定组织（如种子）中获得较低水平的硫代葡萄糖苷。s -35-葡萄糖苷（但-3-烯基硫代葡萄糖苷）和s -35-脱硫葡萄糖苷在油菜植物中的韧皮部迁移率已经从组织分布模式以及观察到的h -3-葡萄糖苷和c -14-蔗糖的一致韧皮部迁移率推断出来。测定了sinigin（2-丙烯基硫代葡萄糖苷）、h -3-葡萄糖苷、35s -脱硫葡萄糖苷、s -35-脱硫葡萄糖苷、c -14-色氨酸、H-3-AIB （α -氨基异丁酸）、并将还原h -3-低聚半乳糖醛酸激发子（聚合度6）和C-14-IAA（吲哚乙酸）的文献值与异种生物韧皮部迁移率的Kleier模型预测值进行了比较。所有上述化合物都显示韧皮部系统性，用蓖麻试验证明，正如模型预测的那样。在pH值4和pH值7下测定硫代葡萄糖苷和脱硫硫代葡萄糖苷的对数k - low（辛醇-水分配系数）值，以及pH值对油菜胚胎吸收的影响，为证明油菜胚胎韧皮部迁移或硫代葡萄糖苷积累中存在弱酸陷阱机制提供了证据。硫代葡萄糖苷的韧皮部移动性可以用中间渗透性假说来解释。综上所述，硫代葡萄糖苷与其他内源性化合物一样，具有Kleier模型所预测的韧皮部移动性的理化性质。
The transport properties of glucosinolates within Brassica napus are of interest as identification of the mechanism of transport could lead to lower levels being obtained in specific tissues such as the seeds. The phloem mobility of S-35-gluconapin (but-3-enylglucosinolate) and S-35-desulphogluconapin in oilseed rape plants has been inferred from tissue distribution patterns, as well as from observed coincident phloem mobility of H-3-gluconapin and C-14-sucrose, The measured relative phloem mobilities for sinigrin (2-propenylglucosinolate), H-3-gluconapin, 35S-desulphogluconapin, S-35-desulphosinigrin, C-14-tryptophan, H-3-AIB (alpha-aminoisobutyric acid), and literature values for a reduced H-3-oligogalacturonide elicitor (degree of polymerization 6) and C-14-IAA (indolylacetic acid), have been compared with the predicted values obtained using the Kleier model for phloem mobility of xenobiotics. All the above compounds show phloem systemicity, demonstrated using the Ricinus assay, as predicted by the model. Log K-ow (octanol-water partition coefficient) values for glucosinolates and desulphoglucosinolates measured at pH 4 and pH 7, and the effect of pH on uptake by oilseed rape embryos are provided as evidence against a weak acid trap mechanism acting in either the phloem mobility or the accumulation of glucosinolates in oilseed rape embryos. The phloem mobility of glucosinolates is explained by the intermediate permeability hypothesis, In conclusion, it would appear that glucosinolates like other groups of endogenous compounds have physicochemical properties allowing phloem mobility as predicted by the Kleier model.