摘要： 为了研究拟南芥CPK6基因在钙离子信号转导过程中的生理功能，进一步明确植物适应缺钙环境的分子机制，首先对CPK6基因缺失突变体（cpk6）进行纯合鉴定，获得了2种纯合突变体：cpk6-2和cpk6-3。通过分析野生型拟南芥Col-0和cpk6突变体在Ca²⁺、Fe²⁺、Mg²⁺、Zn²⁺、Mn²⁺二价阳离子缺失培养基上的生长表型，结果发现，拟南芥cpk6突变体在缺Ca²⁺条件下，相对野生型Col-0，表现出生长受抑制的表型。构建含有CPK6启动子驱动β-葡萄糖苷酸酶基因（GUS）的转基因材料，通过GUS组织化学染色法，发现CPK6启动子在叶片生长点部位和根上有活性，并且在缺Ca²⁺条件下，CPK6启动子在叶片中的活性明显增强。通过原子吸收光谱法，发现拟南芥野生型Col-0和cpk6突变体之间，在对照和缺Ca²⁺条件下，总钙含量没有显著差别，表明CPK6基因不影响植物对钙的吸收和积累。利用组织化学染色法和荧光探针，结果发现，缺Ca²⁺条件下，cpk6突变体根和叶中H₂O₂的积累量明显高于Col-0，表明CPK6是介导缺Ca²⁺诱导植物积累H₂O₂的负调控因子。

关键词: Ca²⁺, 拟南芥, CPK6, GUS, H₂O₂

Abstract: The objective was to research the physiological function of CPK6 in Ca²⁺ signal transduction and to reveal the mechanism of plants to adapt to Ca²⁺ deficient environment. By homozygous identification of the CPK6 deletion mutant (cpk6), two homozygous mutants, cpk6-2 and cpk6-3 were obtained. And the growth phenotype of wild-type Arabidopsis Col-0 and cpk6 mutants in the deficiency of Ca²⁺, Fe²⁺, Mg²⁺, Zn²⁺ and Mn²⁺ were analyzed. The results showed that the mutants showed a growth-inhibiting phenotype relative to wild-type Col-0 in the deficiency of Ca²⁺. The Arabidopsis transgenic material expressing CPK6 promoter-driven β-glucuronidase were obtained. Using GUS histochemical staining, it was found that CPK6 promoter had activity in the roots and the growth point of the leaves. And the activity of CPK6 promoter in leaves was visibly enhanced under Ca²⁺ deficient condition. The total Ca content of Col-0 and cpk6 was determined by atomic absorption spectrometry (AAS). It was found that there was no significant difference in Ca content between Col-0 and cpk6 under control and Ca²⁺ deficiency conditions. The results indicated that CPK6 gene did not participate in the absorption and accumulation of Ca in Arabidopsis. Using histochemical staining and fluorescent probes methods, it was found that the accumulation of H₂O₂ in the leaves and roots of cpk6 was visibly higher than that in Col-0 under Ca²⁺ deficient condition. The results showed that CPK6 was a negative regulator of the accumulation of H₂O₂ induced by Ca²⁺ deficiency in plants.

Key words: Ca²⁺, Arabidopsis thaliana, CPK6, GUS, H₂O₂

中图分类号: 

• Q945.78