海巴戟果实发育过程中果糖、果糖激酶及其基因的变化

Changes in Fructose, Fructokinase and Its Gene in Morinda citrifolia during Fruit Development

摘要:

为揭示海巴戟果实风味形成机制，对果实发育过程的果糖激酶（FRK）活性及其基因的表达模式进行了研究。结果表明，海巴戟果实中的果糖、蔗糖、葡萄糖含量随发育不断积累，均在果实完全成熟时达到最高值，而果糖激酶活性随果实发育不断下降。从果实中克隆了果糖激酶基因TRINITY_DN17192_c0_g1，命名为McFRK2，GenBank登录号为MW380742，其ORF全长为984 bp，编码327个氨基酸，与咖啡（Coffea arabica）的FRK2氨基酸序列相似性为98%。qRT-PCR表明，McFRK2的表达量在果实发育过程中呈下降趋势，当果实成熟时表达的趋于平稳，与果糖激酶活性变化趋势一致。因此，McFRK2可能通过调控果实果糖激酶活性而参与糖代谢，对调控果实风味的形成具有重要作用。

Abstract:

To reveal the formation mechanism of fruit flavor in Morinda citrifolia, the activity and expression pattern of fructokinase (FRK) gene during fruit development were studied. The results showed that the contents of fructose, sucrose and glucose in fruit of M. citrifolia accumulated with the development of fruit, and reached the highest when the fruit was fully mature, while the activity of fructokinase decreased with the development of the fruit. The fructokinase gene TRINITY_DN17192_c0_g1, named as McFRK2 was cloned from M. citrifolia fruit, with 984 bp ORF, encoding 327 amino acids, and the GenBank accession number was MW380742. The amino acid sequence of McFRK2 was similar to that of FRK2 of coffee (Coffea arabica) at 98%. By using qRT-PCR, the expression of McFRK2 decreased gradually during fruit development. When the fruit was ripe, the expression of McFRK2 tended to be stable, which was consistent with the change trend of fructokinase activity. Therefore, McFRK2 might be involved in glucose metabolism by regulating fructokinase activity in fruits, which plays an important role in regulating fruit flavor formation.