板栗野生和芽变雄花序赤霉素合成关键酶基因比较分析

为探明芽变雄花序赤霉素含量降低的分子机制,对板栗野生和芽变雄花序赤霉素合成关键酶基因古巴焦磷酸合成酶(CPS)、贝壳杉烯合成酶(KS)、贝壳杉烯氧化酶(KO)、贝壳杉烯酸氧化酶(KAO)、赤霉素20-氧化酶1(GA20ox1)和赤霉素3-氧化酶1(GA3ox1)的cDNA序列,以及KO基因DNA序列进行了比对,结果表明:两类花序中KO基因在开放阅读框的872、1 115和1 150bp存在3处碱基差异,分别造成了氨基酸由Glu、Tyr和Tyr突变为Gly、Phe和His,最终导致了跨膜区的改变,且发现cDNA上碱基突变是由DNA的碱基差异造成的。推测KO基因的这种突变导致板栗短雄花序性状。

Comparation of key enzymes of gibberellin biosynthesis between normal catkin and short catkin in Castanea mollissima Bl.

This paper is concerned on the molecular mechanisms of gibberellin decrease in mutant catkins.We used cDNA sequence alignment of the gibberellin biosynthesis key enzymes ent-copalyl diphosphate synthase(CPS),ent-kaurene synthase(KS),ent-kaurene oxidase(KO),ent-kaurenoic acid oxidase(KAO),GA 20-oxidase 1(GA20ox1) and GA 3-oxidase 1(GA3ox1),and KO DNA sequence alignment between wild type and mutant catkins.The result revealed that there were three different bases in 872,1 115 and 1 150 bp in KO open reading frame,which converted Glu,Tyr,Tyr to Gly,Phe,His,leding to the change of the transmembrane region.The cDNA point mutations were caused by sequence differences of DNA.It is speculated that the short catkin may be caused by the mutation of the KO gene.