植物V-H^+-ATP酶的昼夜活性变化规律及其A亚基的同型(isoform)表达现象  

Circadian Rhythm of Proton Transport and Isoforms of Subunit A of V-H^+-ATPase in The Vacuolar Membranes from Different Plant Species

作　　者：李平平[1] 宋玉珍[2] 徐泽恒[3] 安志刚[3] 李家磊[3] 

机构地区：[1]东北林业大学盐碱地资源环境研究中心,哈尔滨150040 [2]东北林业大学林学院,哈尔滨150040 [3]东北林业大学森林植物生态学教育部重点实验室,哈尔滨150040

出　　处：《农业生物技术学报》2011年第3期449-454,共6页Journal of Agricultural Biotechnology

基　　金：东北林业大学科研启动经费(No.220-602021)资助

摘　　要：在植物细胞内,V-H+-ATP酶通过将H+转移到液胞内形成跨膜的电化学势梯度来促进其它物质的跨膜运输交换。本研究首次就冰叶日中花(Mesembryanthemum crystallinum)、玉米(Zeamays)、芹菜(Aplumgraveolens)和胡萝卜(Daucus carota)细胞中V-H+-ATP酶活性的昼夜变化规律及其A亚基的同型表达现象用生物化学方法进行了观察和研究。多次的重复实验观察结果证明,V-H+-ATP酶活性变化在冰叶日中花叶片液泡膜中呈现2个峰值,分别在3和18h,而芹菜、胡萝卜和玉米中都出现单一峰值,芹菜和胡萝卜的峰值出现在15和12h,玉米峰值出现在15～18h。叶片组织中V-H+-ATP酶A亚基同型表达现象和冰叶日中花A亚基2个亚基表达稳定,不受盐胁迫和昼夜过程影响;玉米A亚基出现4个同型亚基,同型亚基表达多达4个,盐胁迫后A亚基同型亚基数量未发生变化,表达稳定;芹菜的昼夜样品中A亚基同型亚基数量没有变化,A亚基有3个亚基表达,盐胁迫下,A亚基出现1个同型亚基表达;胡萝卜的A亚基在昼夜过程中发生显著变化,在8h,A亚基有2个同型亚基表达,18h没有显示同型亚基表达,在盐胁迫下A亚基同型亚基数量没有变化。上述不同物种间的V-H+-ATP酶活性变化和同型亚基表达数目的不同是这些植物特有的现象,这对研究同型亚基的基因表达和沉默规律提供了直接的酶学和蛋白质学研究基础。The V-H＋-ATPase in plant cell transports can proton into the vacuole and forms the electrochemical gradients across the membranes,which energizes the secondary transport systems presented on the membranes.We applied plants Mesembryanthemum crystallinum,Zea mays,Aplum graveolens,and Daucus carota,and initially observed that the V-H＋-ATPase from different plant species performed special active peaks of the proton transportation and vary isoforms of subunit A during circadian rhythm and/or stress.Repeat experimental results showed that there were two strong peaks of proton transportation in the leaves of M.crystallinum occurred at the time of 3 and 18 o＇clock,respectively.In the leaves of A.graveolens,D.carota and Z.mays only one strong peak was observed：the active peak in the leaves of A.graveolens and D.carota was observed at 15 and 12 o＇clock,respectively;the active peaks in the leaves of Z.mays was revealed during the time periods of 15~18 o＇clock.The expressions of the isoforms of the subunit A of the V-H＋-ATPase from above plant were observed：two isoforms were revealed in the leaves of M.crystallinum,which was not affected by salt stress and day/night change;four isoforms of the subunit A were observed in the leaves of Z.mays,the number of the isoforms was not affected by salt stress;three isoform of the subunit A from the leaves of A.graveolens did not show much differences during day/night change,but appeared a new isoform after salt stress;In the leaves of D.carota,the isoform of the subunit A was changed during day/night time period,at 8 o＇clock two isoforms were observed,while at 18 o＇clock only one was revealed,the isoforms of the subunit A from D.carota were not affected by salt stress.The proton transportation and the isoforms of the subunit A of the V-H＋-ATPase from above plant species suggest the specific phenomenon related plant species,which may be an interesting base for the studies of the role of gene silencing and proteases.

关 键 词：V-H^+-ATP酶 A亚基 同型亚基 胁迫 冰叶日中花 玉米 胡萝卜 芹菜 

分 类 号：S512.1[农业科学—作物学]