Arabidopsis thaliana CML25 mediates the Ca(2+) regulation of K(+) transmembrane trafficking during pollen germination and tube elongation.
Arabidopsis thaliana CML25 mediates the Ca(2+) regulation of K(+) transmembrane trafficking during pollen germination and tube elongation.
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DOI：
10.1111/pce.12559
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发表时间：
2015-11
期刊：
影响因子：
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通讯作者：
Shuang-Shuang Wang-Shuang;Wenzhu Diao;Xue Yang;Zhu Qiao;Meirong Wang;B. Acharya;Wei Zhang
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文献类型：
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作者：
Shuang-Shuang Wang-Shuang;Wenzhu Diao;Xue Yang;Zhu Qiao;Meirong Wang;B. Acharya;Wei Zhang
胞内游离钙离子（[Ca（2+）]cyt）是植物中常见的第二信使，在花粉萌发和花粉管伸长过程中起着重要作用。在这里，我们证明了CML 25，钙调素样蛋白的成员，具有Ca（2+）结合活性，并在花粉粒萌发，管伸长和结实的作用。CML 25在成熟的花粉粒和花粉管中表达丰富，其产物CML 25蛋白主要定位于细胞质中。两个独立的CML 25功能丧失T-DNA插入突变体遭受了花粉萌发率和花粉管伸长的主要减少。同时，突变体花粉对外界K（+）和Ca（2+）浓度的敏感性也低于野生型花粉。CML 25的破坏增加了花粉粒和花粉管中的[Ca（2+）]cyt，这反过来又削弱了由这些材料（花粉粒和花粉管）制备的原生质体中全细胞内向K（+）电流的Ca（2+）依赖性抑制。cml 25 -1突变体的互补导致野生型表型的恢复。我们的研究结果表明，在花粉萌发和花粉管伸长过程中，CML 25是Ca（2+）介导的K（+）内流调节的一个重要转导子。
The concentration alteration of cytosolic-free calcium ([Ca(2+) ]cyt ) is a well-known secondary messenger in plants and plays important roles during pollen grain germination and tube elongation. Here we demonstrate that CML25, a member of calmodulin-like proteins, has Ca(2+) -binding activity and plays a role in pollen grain germination, tube elongation and seed setting. CML25 transcript was abundant in mature pollen grains and pollen tubes, and its product CML25 protein was primarily directed to the cytoplasm. Two independent CML25 loss-of-function T-DNA insertion mutants suffered a major reduction in both the rate of pollen germination and the elongation of the pollen tube. Also, pollen grains of cml25 mutants were less sensitive to the external K(+) and Ca(2+) concentration than wild-type pollen. The disruption of CML25 increased the [Ca(2+) ]cyt in both the pollen grain and the pollen tube, which in turn impaired the Ca(2+) -dependent inhibition of whole-cell inward K(+) currents in protoplasts prepared from these materials (pollen grain and pollen tube). Complementation of cml25-1 mutant resulted in the recovery of wild-type phenotype. Our findings indicate that CML25 is an important transducer in the Ca(2+) -mediated regulation of K(+) influx during pollen germination and tube elongation.