Guard cell-specific inhibition of Arabidopsis MPK3 expression causes abnormal stomatal responses to abscisic acid and hydrogen peroxide
Guard cell-specific inhibition of Arabidopsis MPK3 expression causes abnormal stomatal responses to abscisic acid and hydrogen peroxide
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DOI：
10.1111/j.1469-8137.2006.01953.x
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发表时间：
2007-01-01
期刊：
影响因子：
9.4
通讯作者：
Morris, Peter C.
中科院分区：
文献类型：
--
作者：
Gudesblat, Gustavo E.;Iusem, Norberto D.;Morris, Peter C.
MAP激酶与保卫细胞信号传导有关。已知拟南芥MAP激酶3（MPK 3）被脱落酸（阿坝）和过氧化氢（H2O2）激活，因此，我们研究了MPK 3在保卫细胞信号转导中的可能作用，这种转基因植物在保卫细胞中含有降低水平的MPK3 mRNA，并且在抑制中显示对阿坝部分不敏感。气孔开放，但正常响应这种激素在气孔关闭。然而，ABA诱导的气孔关闭减少时，细胞质碱化与丁酸钠防止与对照组相比。MPK3反义植物对外源H2O2不太敏感，无论是抑制气孔开放还是促进气孔关闭，因此MPK3是该化合物信号传导所必需的。ABA诱导的H2O2合成在这些植物中正常，表明MPK 3可能在H2O2的下游信号转导中起作用。这些结果为MPK 3在保卫细胞感受阿坝和H2O2中的重要作用提供了明确的证据。
MAP kinases have been linked to guard cell signalling. Arabidopsis thaliana MAP Kinase 3 (MPK3) is known to be activated by abscisic acid (ABA) and hydrogen peroxide (H2O2), which also control stomatal movements.We therefore studied the possible role of MPK3 in guard cell signalling through guard cell-specific antisense inhibition of MPK3 expression.Such transgenic plants contained reduced levels of MPK3 mRNA in the guard cells and displayed partial insensitivity to ABA in inhibition of stomatal opening, but responded normally to this hormone in stomatal closure. However, ABA-induced stomatal closure was reduced compared with controls when cytoplasmic alkalinization was prevented with sodium butyrate. MPK3 antisense plants were less sensitive to exogenous H2O2, both in inhibition of stomatal opening and in promotion of stomatal closure, thus MPK3 is required for the signalling of this compound. ABA-induced H2O2 synthesis was normal in these plants, indicating that MPK3 probably acts in signalling downstream of H2O2.These results provide clear evidence for the important role of MPK3 in the perception of ABA and H2O2 in guard cells.