大白菜-甘蓝易位系A-4硫苷及BrAOP2表达和序列分析

Analysis of Glucosinolates Content and the BrAOP2 Gene Expression and Sequence in Chinese Cabbage-Cabbage Translocation Line A-4

硫苷是十字花科植物中一类重要的次生代谢产物,硫苷及其降解产物在植物风味、抗虫抗逆以及防癌抗癌方面具有重要作用。4-甲磺酰基丁基硫苷(GRA,glucoraphanin)的降解产物萝卜硫素是迄今为止已知的抗癌活性最强的物质之一。BrAOP2基因是影响GRA含量的关键基因。为了探究大白菜-甘蓝易位系A-4与亲本大白菜85-1中硫苷含量的差异,本研究以84株A-4自交后代植株和85-1为材料,通过高效液相色谱法测定其莲座期莲座叶、结球初期莲座叶、结球初期球叶、收获期莲座叶和收获期球叶的硫苷含量,并进行BrAOP2基因表达量和序列分析。结果表明:A-4自交后代植株总硫苷含量、脂肪族硫苷含量、PRO、GBN、GRA、NAP、GBC含量平均值在不同时期的球叶和莲座叶中始终高于85-1,且均在结球初期球叶中含量最高;除NEO含量外,总硫苷含量和其他硫苷组分在球叶中的含量高于莲座叶。A-4自交后代植株BrAOP2基因表达量显著低于85-1,且二者BrAOP2基因序列存在SNP和InDel的变异。由此推测,A-4自交后代植株GRA含量升高与BrAOP2低表达有关。以上研究为进一步分析大白菜-甘蓝易位系GRA含量与85-1的差异奠定基础。

Glucosinolates(GSLs)are a type of important secondary metabolites in cruciferous plants.GSLs and their degradation products are known with important roles in plant flavor,insect resistance and anticancer.Sulforaphane,the degradation product of glucoraphanin(GRA),is one of the most important anti-cancer substances.The BrAOP2 gene is a key factor that modulates the GRA content.To analyze if the GSLs content between the Chinese cabbage-cabbage translocation line A-4 was different with that of their parent Chinese cabbage 85-1,84 selfing progenies plants of A-4 and 85-1 were subjected to measure the GSLs content by High Performance Liquid Chromatography in rosette leaves and heading leaves at rosette,early heading and harvest head stage.The genomic and transcriptional diversity of the BrAOP2 gene were analyzed.The results showed that the average contents of total GSLs,aliphatic GSLs,PRO,GBN,GRA,NAP and GBC of A-4 selfing progenies plants were always higher than those of 85-1 in heading leaves and rosette leaves at all stages.Especially,the highest value on contents were observed in heading leaves at early heading stages.Except the content of NEO,the contents of total GSLs and other GSLs components in heading leaves were higher than those in rosette leaves.The lower expression,SNP and InDel of the BrAOP2 gene in A-4 selfing progenies plants if compared to 85-1 were observed.With these results,it is speculated that the increase on GRA content in A-4 selfing progenies plants associates with the expression of BrAOP2.Collectively,these results provided insights for further analyzing the GRA content in 85-1 and Chinese cabbage-cabbage translocation lines.