Manipulation of biosynthesis of aliphatic glucosinolates by gene replacement and RNAi gene silencing

摘要

Glucosinolates are a large group of plant secondary metabolites found mainly in the order Capparales. Manipulation of biosynthesis of aliphatic glucosinolates was attempted using gene replacement and RNAi gene silencing. Experiments were conducted to replace the functional Alk allele in Brassica rapa with the non functional Alk allele from Brassica oleracea (broccoli)to develop glucoraphanin-rich B. rapa. Gene introgression lines but no gene replacement lines were obtained. Four MAM-like genes involved in glucosinolate biosyntheses, MAM1(At5g23010), MAML(At5g23020), MAML-3 (At1g18500) and MAML-4 (At1g74040) were silenced by RNAi techniques in Arabidopsis and the resulting glucosinolate profiles were studied. All four MAM-like genes, MAM1, MAML, MAML-3 and MAML-4 were shown to be involved in the aliphatic glucosinolate elongation pathway.