生长素作用方式的分子动力学模拟研究  

Molecular Dynamics Simulation Study on the Interaction Mode of Auxin Perception

作　　者：贾雪冰[1] 张鋆[1] 孙宏伟[1] 陈兰[1] 沈荣欣[1] 赖城明[1] 

机构地区：[1]南开大学化学学院,天津300071

出　　处：《化学学报》2010年第24期2500-2508,共9页Acta Chimica Sinica

基　　金：国家高技术研究发展专项经费(No.2006AA10A213)资助项目

摘　　要：针对植物生长素、受体TIR1、辅酶InsP6和IAA7底物多肽链进行5组14个体系的分子动力学模拟研究,比较分析了4个生长素分子IAA,1-NAA,2,4-D和2-NAA与受体TIR1之间的相互作用方式以及辅酶InsP6和IAA7底物多肽链在早期生长素反应中所起的作用.计算结果表明,生长素与TIR1的结合能力与生长素活性顺序一致,生长素的分子结构对于反应活性具有重要影响;中心水分子与生长素之间的氢键作用使得生长素的位置取向有利于与TIR1形成强相互作用;辅酶InsP6与TIR1形成多个氢键使活性口袋结构稳定,保证生长素有效地与活性位点结合;在结合生长素后,IAA7运动加剧,使得生长素犹如激活IAA7多肽活性的"引发器",进而引发进一步的生长素反应.The molecular dynamics simulation studies on the 14 auxin perception systems that comprise auxins,receptor TIR1,cofactor InsP6 and IAA7 substrate peptide are carried out to investigate the interaction mode between receptor TIR1 and the four auxins of IAA,1-NAA,2,4-D and 2-NAA,respectively.The importance of cofactor InsP6 and IAA7 substrate peptide in early auxin perception was also discussed.MD simulations show that the binding intensity between auxins and TIR1 is consistent with auxin activity;the molecular structure has an important impact on auxin activity;multiple center-waters pull auxins to suitable position where auxins can strongly bind with TIR1 through the hydrogen bonds;the hydrogen bonds between InsP6 and TIR1 make the binding pocket stable to ensure auxins to bind effectly;in addition,IAA7 becomes more active after binding with auxins,which means auxins ignite the activity of IAA7 as the trigger to induce the further gene expression of auxin perception.

关 键 词：生长素反应 受体TIR1 IAA7底物多肽 分子动力学模拟 

分 类 号：Q946[生物学—植物学]