El-Kady Ayman, Klenova Elena
Genetics Unit, Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK.
FEBS Lett. 2005 Feb 28;579(6):1424-34. doi: 10.1016/j.febslet.2005.01.044.
CTCF is a transcription factor involved in various aspects of gene regulation. We previously reported that CTCF function is modulated by protein kinase CK2. In this report we investigate further the role of CK2 in regulating the transcriptional properties of CTCF. We demonstrate that coexpression of CTCF with CK2 switches function of CTCF from repressor to activator. The non-phosphorylatable mutant increases repression by CTCF and potentiates the growth-suppressive ability of the protein, whereas the phospho-mimetic mutant behaves in the opposite fashion. Mutation of the individual serines reveals that Serine 612 is a critical residue in regulation of CTCF by CK2.
CTCF是一种参与基因调控多个方面的转录因子。我们之前报道过CTCF的功能受蛋白激酶CK2调节。在本报告中，我们进一步研究了CK2在调节CTCF转录特性中的作用。我们证明，CTCF与CK2共表达可使CTCF的功能从阻遏物转变为激活剂。不可磷酸化突变体增强了CTCF的阻遏作用，并增强了该蛋白的生长抑制能力，而模拟磷酸化突变体的作用则相反。对单个丝氨酸的突变分析表明，丝氨酸612是CK2调节CTCF的关键残基。
