Protein kinase CK2 interacts with and phosphorylates the Arabidopsis circadian clock-associated 1 protein.
Protein kinase CK2 interacts with and phosphorylates the Arabidopsis circadian clock-associated 1 protein.
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DOI：
10.1073/pnas.95.18.11020
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发表时间：
1998-09
影响因子：
11.1
通讯作者：
Shoji Sugano;Christos Andronis;Rachel M. Green;Zhi-Yong Wang;Elaine M. Tobin
中科院分区：
文献类型：
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作者：
Shoji Sugano;Christos Andronis;Rachel M. Green;Zhi-Yong Wang;Elaine M. Tobin
在拟南芥中，生物钟相关1 （CCA1）基因编码myb相关转录因子，该转录因子已被证明参与光敏色素调控Lhcb1*3基因的表达和昼夜节律振荡器的功能。通过酵母相互作用筛选来鉴定与CCA1相互作用的蛋白，我们分离出一个编码蛋白激酶CK2调控亚基的cDNA克隆，并将其命名为CKB3。CKB3是在任何生物体中发现的CK2的第三个β亚基的唯一报道的例子。在酵母双杂交系统和体外相互作用试验中，CKB3与CCA1特异性相互作用。CK2的其他亚基在体外也显示出与CCA1的相互作用。CK2 β亚基刺激CCA1与Lhcb1*3基因启动子上的CCA1结合位点结合，重组CK2能够在体外磷酸化CCA1。此外，拟南芥植物提取物含有ck2样活性，影响含有CCA1的dna -蛋白复合物的形成。这些结果表明，CK2可以通过直接相互作用和磷酸化CCA1蛋白来调节CCA1的活性，CK2可能在体内的CCA1功能中发挥作用。
The circadian clock-associated 1 (CCA1) gene encodes a Myb-related transcription factor that has been shown to be involved in the phytochrome regulation of Lhcb1*3 gene expression and in the function of the circadian oscillator in Arabidopsis thaliana. By using a yeast interaction screen to identify proteins that interact with CCA1, we have isolated a cDNA clone encoding a regulatory (beta) subunit of the protein kinase CK2 and have designated it as CKB3. CKB3 is the only reported example of a third beta-subunit of CK2 found in any organism. CKB3 interacts specifically with CCA1 both in a yeast two-hybrid system and in an in vitro interaction assay. Other subunits of CK2 also show an interaction with CCA1 in vitro. CK2 beta-subunits stimulate binding of CCA1 to the CCA1 binding site on the Lhcb1*3 gene promoter, and recombinant CK2 is able to phosphorylate CCA1 in vitro. Furthermore, Arabidopsis plant extracts contain a CK2-like activity that affects the formation of a DNA-protein complex containing CCA1. These results suggest that CK2 can modulate CCA1 activity both by direct interaction and by phosphorylation of the CCA1 protein and that CK2 may play a role in the function of CCA1 in vivo.