关键词: 大白菜, 紫心, 花青素, 分布, 基因表达分析

Abstract: To investigate the mechanism of anthocyanin production in our new purple-heading Chinese cabbage[Brassica campestris L. ssp. pekinensis（Lour）Olsson]，the expression of structural genes and regulatory genes involved in anthocyanin biosynthesis was examined between the purple line （11S96）and its non-purple parent（09S17）by the real-time fluorescent quantitative RT-PCR，as well as their leaves cross-section were observed and the total anthocyanin content was measured. Leaf cross-section showed that the anthocyanin distribution is non-uniform in the purple heading leaf，specially enriched in the epidermis and its adjacent mesophyll cells. Comparison with the negligible amount of anthocyanin in the non-purple parent，the anthocyanin in purple line is up to 0.79 mg · g^-1 FW in purple inner heading leaves. Q-PCR analysis indicated that the EBGs（Early Biosynthesis Genes）CHS，CHI，F3H，F3′H，LBGs（Late Biosynthesis Genes）UFGT and GST，as well as the regulatory gene MYB0 were up-regulated in the inner leaves of purple heading；the other three LBGs，DFR，ANS，LDOX and the regulatory genes MYB2，MYB4，MYB12 and MYB111 were high up-regulated in all the leaves of the purple heading，which means that there is probably close relationship between these genes and the anthocyanin accumulation in this purple-heading Chinese cabbage，and MYB2 and MYB4 may play the dominant role in it.

Key words: Chinese cabbage, purple-heading, anthocyanin, distribution, gene expression analysis