Phean-o-pas Srivilai, Limpaseni Tipaporn, Buaboocha Teerapong
Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok, Thailand.
BMB Rep. 2008 Nov 30;41(11):771-7. doi: 10.5483/bmbrep.2008.41.11.771.
Calmodulin (CaM) proteins, members of the EF-hand family of Ca(2+)- binding proteins, represent important relays in plant calcium signals. Here, OsCam1-1 was isolated by PCR amplification from the rice genome. The gene contains an ORF of 450 base pairs with a single intron at the same position found in other plant Cam genes. A promoter region with a TATA box at position-26 was predicted and fused to a gus reporter gene, and this construct was used to produce transgenic rice by Agrobacterium-mediated transformation. GUS activity was observed in all organs examined and throughout tissues in cross-sections, but activity was strongest in the vascular bundles of leaves and the vascular cylinders of roots. To examine the properties of OsCaM1-1, the encoding cDNA was expressed in Escherichia coli. The electrophoretic mobility shift when incubated with Ca(2+) indicates that recombinant OsCaM1-1 is a functional Ca(2+)-binding protein. In addition, OsCaM1-1 bound the CaMKII target peptide confirming its likely functionality as a calmodulin.
钙调蛋白（CaM）是EF手型钙离子结合蛋白家族的成员，是植物钙信号传导中的重要传递者。本文通过PCR扩增从水稻基因组中分离出了OsCam1-1。该基因包含一个450个碱基对的开放阅读框，在其他植物CaM基因的相同位置有一个内含子。预测了一个在-26位置带有TATA框的启动子区域，并将其与gus报告基因融合，通过农杆菌介导的转化，利用该构建体培育出了转基因水稻。在所有检测的器官以及横切面上的整个组织中均观察到GUS活性，但在叶片的维管束和根的维管束中活性最强。为了研究OsCaM1-1的特性，将编码cDNA在大肠杆菌中表达。与Ca(2+)一起孵育时的电泳迁移率变化表明重组OsCaM1-1是一种功能性钙离子结合蛋白。此外，OsCaM1-1与CaMKII靶肽结合，证实了其作为钙调蛋白的可能功能。
