摘要
ROP2(Rho-related GTPases from plant)为植物中特有的小G蛋白Rho家族的成员,参与植物细胞信号转导过程。为了探讨其在生长素信号响应过程中对细胞膜泡运输的调控作用,构建了拟南芥ROP2过表达(OX-ROP2)、组成激活型表达(CA-rop2)和显性失活型表达(DN-rop2)的载体,分别转化到膜泡标记和生长素结合蛋白ABP1(auxin binding protein 1)调控表达的烟草BY2细胞系,结合生长素处理开展了ROP2对细胞生长素作用下膜泡运输的调控。在生长素IAA作用下,ROP2的过表达和组成激活型表达都能明显促进细胞的膜泡外排运输,而ROP2的显性失活型表达则抑制细胞膜泡外排运输。如果同时诱导细胞中ABP1过表达,能显著增强ROP2对膜泡外排运输的促进作用,而ABP1受干扰抑制表达时,ROP2的过表达及组成型激活表达对膜泡外排的促进作用都受到明显抑制。IAA处理细胞2 min时就可以观察到细胞对IAA信号响应的膜泡运输明显变化,此时细胞核向内膜系统、内膜系统向细胞质膜之间的膜泡外排运输逐渐增强,外排运输的方向趋向于生长素高浓度方向更活跃。该研究说明,植物ROP2参与生长素快速响应的信号转导途径,能促进膜泡朝向生长素浓度较高的一侧外排运输。
The ROP2 （Rho-related GTPases from plant）, a member of the small G protein Rho family, are only found in plant and involved in cell signal transduction. In order to investigate the auxin signal response to regulating the cell vesicle transport, we cloned the cDNA of ROP2 from Arabidopsis and constructed the over ex- pression （OX-ROP2） and constitutively active expression （CA-rop2） and the dominant negative （DN-rop2） vectors, and then transformed into membrane labeled BY-2 cell lines in which the expression auxin binding protein 1 （ABP1） is inducible. With the treatment of IAA that the over expression of ROP2 and the expression of constitutively active CA-rop2 the cell vesicular exocytosis were obliviously enhanced in the cells. The vesicular exocytosis became even more active when ABP 1 was induced to over expression previously. However, the expression of dominant-negative DN-rop2 inhibited the vesicular transport even the ABP1 was induced to over expression previously. The promotion of vesicular transport by OX-ROP2 and CA-rop2 was suppressed in ABP1 inhibited BY2 cells. Time-lapse observation suggested that vesicular transport induced by auxin occurred within 2 minutes only. When the cells were treated with a grade IAA, the vesicular transport from nucleus membrane to cytoplasm systems and then to plasma mem- ber appeared active and moved to auxin higher concentration side in CA-rop2 and ABP1 over expressed BY2 cells.These results indicate that ROP2 is involved in the ABP1 mediated vesicular transport response in plant cell.
出处
《中国细胞生物学学报》
CAS
CSCD
2016年第5期510-518,共9页
Chinese Journal of Cell Biology
基金
湖南省教育厅科学研究项目(批准号:15K060)资助的课题~~
