Regulation of Hh/Ci signaling by Cos2 and its partners

描述（由申请人提供）：我的实验室的长期目标是了解Hedgehog（Hh）信号是如何转导的，以控制各种各样的细胞行为。分泌蛋白家族控制着动物发育的许多方面。Hh信号传导的功能障碍与包括癌症在内的许多人类疾病有关。Hh家族成员通过进化上保守但定义不明确的信号转导级联发挥其生物学影响。Hh信号转导中的关键步骤是Cubitus interruptus（Ci）的激活，其由含有驱动蛋白相关蛋白Costal 2（Cos 2）的大蛋白复合物调节。我们已经开发了一种新的方法来检测Cos 2相互作用的蛋白在体内，并确定了几个新的组件Cos 2/Ci复合物。在拟议的研究中，我们将使用遗传，生物化学，细胞和药理学的方法相结合，以调查Cos 2和它的相互作用的蛋白质调节Ci磷酸化，活性和亚细胞定位的机制。具体而言，我们计划1）研究不同的Cos 2复合物调节Ci核转位的机制; 2）研究GSK 3/Cos 2相互作用在Ci磷酸化中的作用和调节; 3）研究酪蛋白激酶I（CKI）在Hh信号传导中的作用及其潜在机制; 4）确定新的Cos 2相互作用蛋白Koro的作用，并鉴定和表征调节Ci活性的另外的Cos 2相互作用蛋白。从拟议的研究中获得的知识将揭示Hh信号如何转导以控制细胞生长和模式，并可能为Hh信号活性的错误调节引起的癌症的诊断和治疗干预提供新的途径。

DESCRIPTION (provided by applicant): The long-term goal of my laboratory is to understand how Hedgehog (Hh) signal is transduced to control a wild variety of cellular behaviors. Hh family of secreted proteins controls many aspects of animal development. Malfunction of Hh signaling has been linked to numerous human disorders including cancers. Hh family members exert their biological influence through an evolutionarily conserved, yet poorly defined signal transduction cascade. A critical step in Hh signal transduction is the activation of Cubitus interruptus (Ci), which is regulated by large protein complexes containing the kinesin-related protein Costal2 (Cos2). We have developed a novel method for detecting Cos2 interacting proteins in vivo and have identified several novel components of Cos2/Ci complexes. In the proposed study, we will use a combination of genetic, biochemical, cellular, and pharmacological approaches to investigate the mechanisms by which Cos2 and its interacting proteins regulate Ci phosphorylation, activity, and subcellular localization. In particular, we plan to 1) investigate the mechanism by which distinct Cos2 complexes regulate Ci nuclear translocation; 2) study the role and regulation of GSK3/Cos2 interaction in Ci phosphorylation; 3) investigate the role of casein kinase I (CKI) in Hh signaling and the underlying mechanism; 4) determine the role of a novel Cos2 interacting protein, Koro, and identify and characterize additional Cos2 interacting proteins that regulate Ci activity. Knowledge gained from the proposed study shall shed light into how Hh signal is transduced to control cell growth and patterning, and may provide new avenues for diagnosis and therapeutic intervention of cancers caused by mis-regulation of Hh signaling activity.