镉胁迫下NO对胡杨细胞Cd^(2+)吸收调控机制的研究  

Mediation of NO on Cd^(2+) uptake in Populus euphratica cells under cadmium stress

作　　者：王少杰[1] 赵楠[1] 申泽丹[1] 撒刚[1] 孙会敏[1] 赵瑞[1] 沈昕[1] 陈少良[1] 

机构地区：[1]北京林业大学生物科学与技术学院

出　　处：《北京林业大学学报》2015年第6期11-16,共6页Journal of Beijing Forestry University

基　　金：国家自然科学基金项目(31270654;31200470);教育部科学技术研究(科学技术类)项目(113013A);人事部留学人员科技活动项目择优资助经费;高等学校学科创新引智计划项目(111 Project;B13007);教育部创新团队发展计划项目(IRT13047)

摘　　要：本文研究了NO对胡杨愈伤细胞Cd2+耐受性的影响。结果表明:Cd2+(50μmol/L)显著抑制了胡杨细胞的生长,而硝普钠SNP(NO供体,25μmol/L)能明显缓解Cd2+对胡杨细胞生长的抑制作用,并减轻镉对细胞膜的伤害以及镉胁迫导致的细胞活力下降。利用非损伤微测技术等研究了NO对Cd2+动态吸收的影响。Cd Cl2(50μmol/L)处理之后,胡杨细胞表现出Cd2+内流,而SNP(25μmol/L,6 h)显著抑制了Cd2+的内流,并降低了Cd2+在细胞内的积累。研究发现,NO是通过调控钙离子通道来抑制胡杨细胞对Cd2+的吸收。镉胁迫下Cd2+内流被钙离子通道专一性抑制剂氯化镧明显抑制,表明Cd2+是通过钙离子通道转运进入细胞。并且发现,NO是通过促进Ca2+的内流来竞争性地抑制胡杨细胞对Cd2+的吸收,从而缓解了镉胁迫对胡杨细胞造成的生长抑制。We investigated the effect of nitric oxide （NO）on cadmium （Cd^2＋） tolerance in Populus euphratica cells. Results showed that 50 μmol/L Cd^2＋ significantly restricted cell growth; however, the inhibition of Cd^2＋ on cell growth was evidently alleviated by the addition of sodium nitroprusside （SNP, nitric oxide donor, 25 μmol/L）. Moreover, SNP could relieve the decline of Cd^2＋-induced cell viability and damage to membrane during the period of cadmium stress. The effect of NO on cadmium kinetics was investigated using the non-invasive micro-test technique （NMT）. After being subjected to 50 μmol/L CdCl2 solution, P. euphratica showed a substantial Cd^2＋ influx. However, the cadmium-induced Cd^2＋ influx and the subsequent accumulation were both significantly restricted by 25 μmol/L SNP. Furthermore, pharmacological experiments showed that NO mediated the Cd^2＋ entry through calcium permeable channels in P. euphratica. The Cd^2＋ influx caused by Cd^2＋ stress was strongly inhibited by lanthanum chloride, a specific inhibitor of calcium channels. Noteworthy, NO was found to increase Ca^2＋ influx, which competitively inhibited the entry of Cd^2＋ through calcium permeable channels. Consequently, the Cd^2＋ uptake and buildup were limited, and thus the growth inhibition by cadmium was alleviated in P. euphratica cells.

关 键 词：胡杨细胞 NO 镉胁迫 镉离子流 钙离子流 钙离子通道 

分 类 号：S718.43[农业科学—林学] S792.119