木薯AGPase酶活性及其同工酶位点检测

The Determination of AGPase Activity and its Isozymes in Cassava

本文以3个亲缘关系较远的高产木薯品种(SC124,SC8和Arg7)为材料,对块根发育过程中的AGPase活性和淀粉含量进行了测定,并利用AGPase同工酶电泳技术(非变性聚丙烯酰胺凝胶电泳)对AGPase酶活性较高时期同工酶位点进行检测,旨在分析木薯块根AGPase同工酶位点与AGPase酶活性和淀粉积累的关系。结果表明:木薯块根发育过程中AGPase酶活性和淀粉含量呈极显著正相关(R=0.80212),Arg7的AGPase酶活性和淀粉含量在块根发育都显著高于SC124和SC8。同工酶分析表明,木薯至少有6个同工酶位点(AGPa,AGPb,AGPc,AGPd,AGPe和AGPf),且品种间具有多态性。其中,3个品种共有的4个同工酶位点分别为AGPa、AGPc、AGPd和AGPf,AGPe位点只在Arg7中出现,初步判断同工酶位点AGPe可能与其较高的酶活性和淀粉含量有关。本研究为系统研究木薯品种间AGPase酶活性与淀粉积累的关系提供了参考。

To explore the relationship of AGPase isozyme locus with its enzyme activity and starch content in cassava （Manihot esculenta Crantz） storage root, in this paper, we employed three high-yield and distant relatived cassava cultivars （SC124, SC8, Arg7） as the tested materials to measure the enzyme activity and starch content of AGPase during the root development processing, and also determined the isozyme loci of AGPase during the period of its enzyme activity relatively higher by using AGPase isozyme electrophoresis technique, which was non-denaturing polyacrylamide gel electrophoresis. The results showed that the activity of AGPase extremely significant positive correlation with starch content （R=0.802 12）, and the enzyme activity and starch content of AG- Pase in Arg7 were both remarkably higher than SC124 and SC8. The isozyme analysis demonstrated that there were at least six isozyme loci （AGPa, AGPb, AGPc, AGPd, AGPe and AGPf） in cassava and manifested polymorphic among the three cultivars, Among of the six loci, there were four isozyme loci in the three cultivars, which was AGPa, AGPc, AGPd and AGPf respectively, interestingly, only Arg7 had the locus of AGPe, therefore, we pri- marily estimated the isozyme loci of AGPe might have same relation with its higher enzyme activity and starch content. This research would provide the refference for systematically investigating the relation between AGPase enzyme activity and starch content among cassava cultivars.