Studies on the Role of DIk/ZIP-Kinase in Mitosis and Cytokinesis

Dlk，或更常被称为ZIP激酶，在调节细胞运动，收缩性和有丝分裂，特别是细胞分裂中起关键作用。在有丝分裂过程中，ZIP激酶与中心体、着丝粒、收缩环和中间体结合。突变体AC2NLS最近揭示的数据表明，ZIP激酶在纺锤体组装和有丝分裂和细胞质分裂的协调中起作用，这些功能涉及与着丝粒的相互作用。在接下来的提案中，我们希望进一步阐明ZIP激酶在着丝粒中的作用以及着丝粒特异性H3T11磷酸化的意义。我们提出ZIP激酶在T11磷酸化组蛋白H3，这种修饰要么是着丝粒特异性组蛋白代码的一部分，要么是随后将CENP-A纳入染色质的信号。为了证明这些假设，我们希望1}以诱导方式表达突变体AC2NLS，并在同步条件下观察其影响；2)确定ZIP激酶在有丝分裂结构中的相互作用伙伴；3)建立诱导敲除系统；4)研究染色体定向纺锤体组装；5)研究H3T11磷酸化的作用。

Dlk, or more commonly termed ZIP kinase, plays a key role in regulation of cell motility, contractility, and mitosis, particularly cytokinesis. During mitosis, ZIP kinase associates with centrosomes, centromeres, the contractile ring and the midbody. Recent data revealed by mutant AC2NLS suggest that ZIP kinase plays a role in spindle assembly and in coordination of mitosis and cytokinesis and that these functions involve interaction with centromeres. In the following proposal we want to further elucidate the role of ZIP kinase at centromeres and the significance of centromere-specific H3T11 phosphorylation. We propose that ZIP kinase phosphorylates histone H3 at T11 and that this modification is either part of a centromere-specific histone code or that it is a signal for subsequent incorporation of CENP-A into chromatin. To proof these assumptions we want to 1} express mutant AC2NLS in an inducible fashion and follow its effects under synchronous conditions, 2) identify the interaction partners of ZIP kinase at mitotic structures, 3) establish inducible knockout systems 4) investigate chromosome-directed spindle assembly 5) investigate the role of H3T11 phosphorylation.