套袋‘红富士’苹果果实山梨醇脱氢酶的活性变化及其表达

以‘红富士’苹果为试材，通过酶活性测定和Western印迹技术，研究了套袋‘红富士’苹果果实山梨醇脱氢酶(SDH)的活性及其表达变化。结果表明，在整个发育过程中，套袋‘红富士’苹果果实的山梨醇含量及SDH活性的变化动态与对照果实基本一致。与对照相比，套袋苹果果实的SDH活性较低，山梨醇含量较高，由此表明套袋影响苹果果实山梨醇代谢。Western blotting结果显示，苹果果实SDH的亚基构成为40 kDa，随着苹果果实的发育，SDH的免疫信号强度逐渐增强。在同一取样时期，套袋苹果果实SDH的免疫信号强度与对照果实相比差异不显著，由此推断，SDH的活性变化可能存在翻译后水平上的调控。

Activity and Expression Changes of Sorbitol Dehydrogenase in Developing Bagging ‘Red Fuji’ Apple Fruit

The changes of sorbitol content,sorbitol dehydrogenase（SDH） activity and protein expression in bagging＇Red Fuji＇apple fruit were studied through enzyme determination and Western blotting technique.The results showed that the sorbitol content and SDH activity in bagging＇Red Fuji＇apple fruit almost had the same dynamic changes as control fruit during the whole developing period.Moreover,the relative lower SDH activity and higher sorbitol content were found in bagging apple fruit compared with control.Therefore,fruit bagging influenced sorbitol metabolism in some extent.On the other hand,Western blotting assay of SDH detected the presence of 40 kDa peptide and the intensity of immune signal in apple fruit increased gradually with fruit developing.However,few significant differences of immune signal existed in bagging and control fruit at the same sampling period.So it was concluded that the changes of SDH activity was regulated at post-translational level.