摘要
为探讨沙棘果实苹果酸积累与相关基因表达间的关系,以偏低酸品种‘橙色’和偏高酸品种‘芬兰’不同发育期(D1～D5期)的果实为试材,测定可溶性固形物和苹果酸含量,采用实时荧光定量PCR分析苹果酸代谢关键基因的表达模式。结果表明,第一,可溶性固形物含量在果实发育过程中呈上升趋势,成熟时(D5期)最高,‘橙色’比‘芬兰’高;苹果酸含量的变化与之相反,果实发育阶段呈下降趋势,成熟时最低,‘橙色’比‘芬兰’低。第二,果实发育过程中,与苹果酸合成相关的PEPC基因表达水平呈下降趋势,且在成熟期(D4～D5期)‘橙色’比‘芬兰’下降迅速;cytMDH基因在‘芬兰’果实的表达整体上呈先升后降趋势,转色期(D3期)为转折点,在‘橙色’各时期的表达水平变化较小。第三,NADP-ME基因在整个果实发育阶段的表达呈上升趋势,‘橙色’比‘芬兰’明显;PEPCK基因的表达在两个品种间存在显著差异,在‘芬兰’中的表达水平变化较小;在‘橙色’中呈现升-降-升-降的趋势,转色期后迅速表达至峰值,与NADP-ME共同作用促进苹果酸在成熟期含量迅速降低,可溶性固形物含量迅速提高。本研究结果为进一步深入探讨沙棘苹果酸代谢调控基因的功能及表达提供科学依据。
To explore the relationship between malic acid accumulation and relevant gene expression in sea buckthorn fruit, the berries of cultivar ’Chengse’ with lower acid taste and cultivar ’Fenlan’ with higher acid taste at different developmental stages(D1-D5) were used as materials. The contents of total soluble solid(TSS) and malic acid were determined and the expression profiles of genes involved in malate metabolism were tested using real-time quantitative PCR. The results showed that the TSS content increased in fruit development and reached the highest at maturity(D5). The berries of ’Chengse’ contained higher TSS in fruit ripening than ’Fenlan’. By contrast, the changes of malic acid content decreased and reached the lowest at maturity. The berries of ’Fenlan’ contained higher malic acid than that of ’Chengse’. In addition, PEPC gene that involved in the biosynthesis of malic acid displayed down-regulated expression in fruit development. In mature period(D4-D5), the decreasing rate of ’Chengse’ was higher. The expression of cytMDH gene in ’Fenlan’ showed a increase-decrease trend,with veraison(D3) as the turning point, while its expression in each period of ’Chengse’ had little difference.Furthermore, NADP-ME gene displayed up-regulated expression in the whole fruit development, which was more significant in berries of ’Chengse’. The expression level of PEPCK had significant difference between these two cultivars. It had little change in each stage of fruit development of ’Fenlan’. However, the change of expression level was increase-decrease-increase-decrease in ’Chengse’, and the maximum appeared in post-veraison(D4). It promoted the rapid loss of malic acid and caused accumulation of TSS content with NADP-ME gene in ripening.These results provided scientific reference for understanding the function and expression of genes involved in malate metabolism regulation in sea buckthorn.
作者
李贺
阮成江
李景滨
王莉
田兴军
Li He;Ruan Chengjiang;Li Jingbin;Wang Li;Tian Xingjun(School of Life Science,Nanjing University,Nanjing,210023;Institute of Plant Resources,Dalian Minzu University,Dalian,116600)
出处
《分子植物育种》
CAS
CSCD
北大核心
2019年第1期65-71,共7页
Molecular Plant Breeding
基金
国家自然科学基金资助项目(31100489
31570681)资助
关键词
沙棘
苹果酸
关键基因
表达分析
Hippophae rhamnoides
Malic acid
Key gene
Expression analysis
