and Regulate the Biosynthesis of Progoitrin Glucosinolate in Chinese Kale.

Progoitrin (2-hydroxy-3-butenyl glucosinolate, PRO) is the main source of bitterness of plants. Research on the biosynthesis of PRO glucosinolate can aid the understanding of the nutritional value in plants. In this study, four ODD genes likely involved in PRO biosynthesis were cloned from Chinese kale. These four genes, designated as , shared 75-82% similarities with the sequence of . The sequences of these four s were analyzed, and and were chosen for further study. The gene showed the highest expression levels in the roots, followed by the leaves, flowers, and stems, which is in accordance with the trend of the PRO content in the same tissues. Both the expression levels of and the content of PRO were significantly induced by high- and low-temperature treatments. The function of involved in PRO biosynthesis was identified. Compared with the wild type, the content of PRO was increased twofold in the over-expressing or plants. Meanwhile, the content of PRO was decreased in the or RNAi lines more than twofold compared to the wildtype plants. These results suggested that and may play important roles in the biosynthesis of PRO glucosinolate in Chinese kale.