State Key Laboratory for Ecological Pest Control of Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China.
Institute of Oceanography, Minjiang University, Fuzhou, China.
Appl Environ Microbiol. 2020 Jan 7;86(2). doi: 10.1128/AEM.02191-19.
CK2, a serine/threonine (Ser/Thr) kinase present in eukaryotic cells, is known to have a vast number of substrates. We have recently shown that it localizes to nuclei and at pores between hyphal compartments in We performed a pulldown proteomics analysis of CK2 catalytic subunit MoCKa to detect interacting proteins. The MoCKa pulldown was enriched for septum and nucleolus proteins and intrinsically disordered proteins (IDPs) containing a CK2 phosphorylation motif that is proposed to destabilize and unfold α-helices. This points to a function for CK2 phosphorylation and corresponding phosphatase dephosphorylation in the formation of functional protein-protein aggregates and protein-RNA/DNA binding. To test this as widely as possible, we used secondary data downloaded from databases from a large range of experiments, as well as data for a relatively closely related plant-pathogenic fungus, We found that CKa expression was strongly positively correlated with Ser/Thr phosphatases, as well as with disaggregases (HSP104, YDJ1, and SSA1) and an autophagy-indicating protein (ATG8). The latter points to increased protein aggregate formation at high levels of CKa expression. Our results suggest a general role for CK2 in chaperoning aggregation and disaggregation of IDPs and their binding to proteins, DNA, and RNA. CK2 is a eukaryotic conserved kinase enzyme complex that phosphorylates proteins. CK2 is known to phosphorylate a large number of proteins and is constitutively active, and thus a "normal" role for a kinase in a signaling cascade might not be the case for CK2. Previous results on localization and indications from the literature point to a function for CK2 phosphorylation in shaping and folding of proteins, especially intrinsically disordered proteins, which constitute about 30% of eukaryotic proteins. We used pulldown of interacting proteins and data downloaded from a large range of transcriptomic experiments in and complemented these with data downloaded from a large range of transcriptomic experiments in We found support for a general role for CK2 in aggregation and disaggregation of IDPs and their binding to proteins, DNA, and RNA-interactions that could explain the importance of CK2 in eukaryotic cell function and disease.
CK2 是一种存在于真核细胞中的丝氨酸/苏氨酸（Ser/Thr）激酶，已知其具有大量的底物。我们最近表明，它定位于核内和菌丝隔室之间的孔中。我们进行了 CK2 催化亚基 MoCKa 的下拉蛋白质组学分析，以检测相互作用的蛋白质。MoCKa 的下拉富集了隔膜和核仁蛋白以及含有 CK2 磷酸化模体的无规卷曲蛋白（IDP），该模体被提议使α-螺旋不稳定和展开。这表明 CK2 磷酸化及其相应的磷酸酶去磷酸化在功能性蛋白质-蛋白质聚集体和蛋白质-RNA/DNA 结合的形成中具有功能。为了尽可能广泛地验证这一点，我们使用从大量实验数据库下载的二级数据以及相对密切相关的植物病原真菌的数据库中的数据进行了测试。我们发现 CKa 的表达与 Ser/Thr 磷酸酶以及解聚酶（HSP104、YDJ1 和 SSA1）和自噬指示蛋白（ATG8）呈强烈正相关。后者表明在 CKa 表达水平较高时，蛋白质聚集体的形成增加。我们的结果表明 CK2 在 IDP 的伴侣聚集和去聚集及其与蛋白质、DNA 和 RNA 的结合中具有普遍作用。CK2 是一种真核保守的激酶酶复合物，可磷酸化蛋白质。CK2 已知可磷酸化大量蛋白质，并且是组成性激活的，因此激酶在信号级联中的“正常”作用可能不适用于 CK2。以前关于定位的结果和文献中的迹象表明 CK2 磷酸化在蛋白质的形成和折叠中的作用，特别是在构成约 30%的真核蛋白质的无规卷曲蛋白质中。我们使用相互作用蛋白质的下拉和从大量转录组实验中下载的数据，并将其与从大量转录组实验中下载的数据进行补充。我们发现 CK2 在 IDP 的聚集和去聚集及其与蛋白质、DNA 和 RNA 的结合中具有普遍作用的证据，这些证据可以解释 CK2 在真核细胞功能和疾病中的重要性。
