植物生长素通过ABP1促进细胞膜泡的外排运输  

ABP1 Mediates Auxin Accelerating of Vesicular Exocytosis in Plant

作　　者：柳叶[1] 王亚红[1] 黄妤[1] 陈宗星[1] 赵燕[1] 张学文[1] 

机构地区：[1]湖南农业大学生物科学技术学院,长沙410128

出　　处：《中国细胞生物学学报》2014年第9期1250-1256,共7页Chinese Journal of Cell Biology

基　　金：湖南省教育厅科学研究项目(批准号:12C0156)资助的课题~~

摘　　要：为了研究植物生长素结合蛋白ABP1（auxin binding protein 1）对膜泡运输的调控,将烟草生长素结合蛋白基因ABP1 cDNA分别构建成可诱导型表达的过表达和干扰表达载体,并将绿色荧光蛋白GFP与烟草分泌载体膜蛋白SCAMP2（secretory carrier membrane protein 2）融合进行细胞的膜泡标记,转化植物模式细胞BY-2后分别获得了转ABP1和antiABP1的两类膜泡标记转基因细胞系。以雌二醇诱导ABP1、antiABP1表达后,结合生长素处理,通过扫描激光共聚焦观察了细胞的膜泡运输变化。当诱导ABP1在细胞内过量表达后,以吲哚-3-乙酸（indole-3-acetic acid,IAA）处理细胞,在细胞核膜及周围内质网膜、细胞质膜以及其他细胞内膜系统都观察到强烈的荧光信号,说明细胞内膜泡运输更为活跃;当诱导antiABP1在细胞内干扰表达时,在细胞核附近维持有较强烈的荧光信号,而细胞质膜及两细胞间隔的荧光信号明显减弱,表明抑制ABP1表达显著抑制了细胞膜泡的外排运输。在ABP1经诱导过表达后,加入IAA处理细胞,在0-6 min时间段内间隔性观察了细胞膜泡对生长素的时间响应,在这段时间内细胞核周围及内膜系统的荧光信号明显增强,细胞质膜的荧光强度没有明显的变化,表明细胞核与内膜系统间存在活跃的膜泡运输,内膜系统向细胞质膜间的外排膜泡运输也逐渐加强。因此,可以证明ABP1参与生长素信号响应,增强细胞膜泡的外排运输。In order to investigate the auxin regulation of vesicular transport in plant cell, we cloned the tobacco auxin binding protein 1 gene（ABP1） cDNA and recombined it into an inducible Ti vector pER16 in either sense or antisense direction. The vesicles labeled BY-2 were prepared by fusion secretory carrier membrane protein 2（SCAMP2） with green f luorescent protein（GFP） and the cell line was further transformed by the two recombinants. The two membrane labeled transgenic BY-2 cell line were screened out and subjected to analysis of the ABP1 mediated auxin regulation of the vesicular transport. The expressions of transgene ABP1 and antiABP1 were first induced by estradiol and then treated with auxin. The vesicles transporting were observed under laser scan confocal microscope. The results showed that the fluorescence signal was significantly enhanced in the nucleus membrane, cytoplasmic membrane, and other endomembrane system when ABP1 was overexpressed. It indicates more active vesicular transportation in intracellular membranes after indole-3-acetic acid（IAA） treatment. The f luorescence signal was only maintained stronger around the nucleus but weak in the cytoplasmic membrane and other endomembrane systems if the ABP1 expression was antisense inhibited, because the vesicular transport was significantly reduced. The phenomena demonstrated that suppression of ABP1 significantly inhibited vesicular exocytosis. After the full estradiol induction of the ABP1 overexpression cell, we carried out a 0~6 min IAA treatment interval observation. The fluorescence signal was enhanced significantly around the nucleus membrane and then into endomembrane systems but with no obvious change in cytoplasmic membrane and two cells intervals. The Results indicated that within 6 min of IAA treatment exocytose vesicular transport was activated firstly between the nucleus and the endomembrane system, and then the exocytose transport between the endomembrane system to the plasma membrane. Thus we conclude that ABP1 is involv

关 键 词：生长素 生长素结合蛋白(ABP1) 膜泡运输 

分 类 号：Q942[生物学—植物学]