DAP-like kinase interacts with the rat homolog of Schizosaccharomyces pombe CDC5 protein, a factor involved in pre-mRNA splicing and required for G2/M phase transition.-猫眼课题宝

DAP 样激酶与粟酒裂殖酵母 CDC5 蛋白的大鼠同源物相互作用，CDC5 蛋白是一种参与前 mRNA 剪接且是 G2/M 相转变所需的因子。

DOI：

发表时间：

2002

期刊：

Nucleic Acids Research

影响因子：

14.9

通讯作者：

中科院分区：

生物学2区

文献类型：

作者：

H. Engemann;Volker Heinzel;G. Page;U. Preuss;K. Scheidtmann

DAP样激酶（Dlk，也称为ZIP激酶）是一种含有亮氨酸拉链的丝氨酸/苏氨酸特异性蛋白激酶，其生物学功能尚不清楚。到目前为止确定的相互作用伙伴是转录因子或蛋白质，可以支持或抵消细胞凋亡。因此，Dlk可能参与调节转录，或者更一般地，参与调节存活或凋亡。在这里，我们报告了一个新的相互作用伙伴，裂殖酵母CDC 5蛋白，一个假定的转录和剪接因子参与G（2）/M转换的大鼠同源物。在体外，大鼠CDC 5与Dlk形成复合物，但不被Dlk磷酸化。相反，它被一种相关的激酶磷酸化，这种激酶被鉴定为CK 2。Dlk的相互作用结构域被映射到亮氨酸拉链，而CDC 5的相互作用结构域被映射到残基500和802之间的C-末端区域。在体内，这两种蛋白质共定位在细胞核中不同的斑点状结构中，其中一些与早幼粒细胞白血病蛋白重叠。有趣的是，剪接因子SC 35，也存在于斑点，被部分取代后过度表达的CDC 5或Dlk，可能是由于磷酸化的Dlk。与以前的数据一起，这些结果表明Dlk可能在协调特定的转录和剪接事件中发挥作用。

DAP-like kinase (Dlk, also termed ZIP kinase) is a leucine zipper-containing serine/threonine-specific protein kinase with as yet unknown biological function(s). Interaction partners so far identified are either transcription factors or proteins that can support or counteract apoptosis. Thus, Dlk might be involved in regulating transcription or, more generally, survival or apoptosis. Here we report on a new interaction partner, the rat homolog of Schizosaccharomyces pombe CDC5 protein, a presumptive transcription and splicing factor involved in the G(2)/M transition. In vitro, rat CDC5 forms complexes with, but is not phosphorylated by, Dlk. Rather, it was phosphorylated by an associated kinase which was identified as CK2. The interaction domain of Dlk was mapped to the leucine zipper, while that of CDC5 was mapped to the C-terminal region between residues 500 and 802. In vivo, both proteins co-localize perfectly in distinct speckle-like structures in the nucleus, some of which overlap with promyelocytic leukemia protein. Interestingly, splicing factor SC35, which also resides in speckles, was partially displaced upon overexpression of either CDC5 or Dlk, perhaps due to phosphorylation by Dlk. Together with previous data, these results suggest that Dlk might play a role in coordinating specific transcription and splicing events.