Function of NudC, a Prolactin Regulated Gene

催乳素调控基因 NudC 的功能

• 批准号: 6773586
• 负责人: LI-YUAN YU-LEE
• 金额: $ 29.27万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-03-15 至 2008-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6773586
• 关键词: RNA interference; biological signal transduction; cell cycle; cell growth regulation; cell proliferation; dynein ATPase; gene induction /repression; genetic regulation; hormone regulation /control mechanism; microscopy; microtubules; mitogens; phosphorylation; prolactin; regulatory gene; tissue /cell culture

DESCRIPTION (provided by applicant): The pituitary hormone prolactin (PRL) stimulates the growth and differentiation of many tissues and cell types. To understand a role of PRL in mitogenic signaling, we isolated a number of immediate early genes activated after PRL stimulation. One such gene, NudC, was cloned as an early growth response gene. Genetic, biochemical and cellular studies show that NudC associates with the microtubule (MT)-dependent dynein/dynactin motor complex that mediates many mitotic processes. Our studies suggest that NudC plays multiple roles in mitosis (nuclear division) and cytokinesis (cytoplasmic division). We showed that altering NudC levels by either small interference RNA (siRNA)-mediated gene silencing or adenovirus-mediated overexpression resulted in defects in cytokinesis, as reflected by an increase in the number of multinucleated cells and cells with persistent intercellular connections. MTs in the midzone and midbody matrix appeared disorganized, providing a possible clue on a cytokinesis defect. In addition, we show that NudC is a mitotic phosphoprotein and it interacts with the mitotic kinase polo-like kinase 1 (Plkl), suggesting that NudC phosphorylation may affect NudC functions during mitosis. We hypothesize that a precise level and phosphorylation state of NudC are required for mitotic progression and completion of cytokinesis, and that NudC functions by regulating the dynein/dynactin complex and MT dynamics during mitosis and cytokinesis. To delineate NudC functions in mitogenic signaling, we propose to 1) Determine NudC function in mitosis and cytokinesis by analyzing how changes in NudC levels and phosphorylation state affect mitosis progression and completion of cytokinesis, and to 2) Analyze regulation of dynein/dynactin by NudC by addressing how NudC regulates dynein complex stability and MT dynamics. These studies should contribute to a fundamental understanding of the mechanisms of PRL-mediated mitogenic signaling.

描述（由申请人提供）：垂体激素催乳素（PRL）刺激许多组织和细胞类型的生长和分化。为了了解PRL在有丝分裂信号中的作用，我们分离了PRL刺激后激活的许多早期基因。这样的基因NUDC被克隆为早期生长反应基因。遗传，生化和细胞研究表明，NUDC与微管（MT）依赖性的Dynein/dynactin运动复合物相关，可介导许多有丝分裂过程。我们的研究表明，NUDC在有丝分裂（核分裂）和细胞因子（细胞质分裂）中起多种作用。我们表明，通过小型干扰RNA（siRNA）介导的基因沉默或腺病毒介导的过表达改变NUDC水平会导致细胞因子的缺陷，这反映了多核细胞的数量增加，并且具有持久的细胞间连接。中区和中体矩阵中的MT显得混乱，为细胞因子缺陷提供了可能的线索。此外，我们表明NUDC是一种有丝分裂磷蛋白，它与有丝分裂激酶类球样激酶1（PLKL）相互作用，表明NUDC磷酸化可能会影响有丝分裂过程中的NUDC功能。我们假设NUDC的精确水平和磷酸化状态是有丝分裂进展和细胞因子的完成所必需的，并且NUDC在有丝分裂和细胞因子过程中调节Dynein/dynactin复合物和MT动力学的功能。为了在有丝分裂信号中描述NUDC的功能，我们建议1）通过分析NUDC水平的变化和磷酸化状态的变化如何影响细胞因子的进展，并通过nudc stroments nudc strongity n udc stemistion来确定有丝分裂和细胞因子的NUDC功能。这些研究应有助于对PRL介导的有丝分裂信号的机制有基本的理解。