Dynamics of epithelial cells and neurons through regulation of dephosphorylation and reactivation of cofilin

通过调节肌动蛋白丝切蛋白的去磷酸化和重新激活来调节上皮细胞和神经元的动力学

• 批准号: 17370069
• 负责人: UEMURA Tadashi
• 金额: $ 9.28万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17370069/
• 关键词: cofilin; actin; epithelium; neuronal process; mouse

Cofilin, a key regulator of actin filament dynamics, is inactivated by phosphorylation at Ser-3 by LIM-kinases and is reactivated by dephosphorylation by a family of protein phosphatases, termed Slingshot (SSH). The human or mouse genome has three copies of Ssh genes (Ssh1-Ssh3). Previous in situ hybridization analyses revealed characteristic patterns of expression of each of the mouse ssh genes in both neuronal and non-neuronal tissues. Here we studied levels of endogenous expression of individual gene products and showed that expression of Ssh-2 and that of Ssh-3 are high in neural and epithelial tissues, respectively. To explore roles of Ssh-3 in epithelial tissues, we isolated derivatives of MDCK cells in which Ssh-3 can be knocked down upon addition of doxycycline. Because we detected Ssh-1 in MDCK cells, we further isolated sublines in which both Ssh-1 and Ssh-3 are knocked down and have been studying phenotypes of cell shape. To examine in vivo roles of Ssh-3 in epithelial morphogenesis, we generated Ssh-3-knock out mice. The Ssh-3-knock out mice are viable and fertile in two different backgrounds and we have been hunting for phenotypes of various epithelial tissues, such as mammary glands and kidney.

Cofilin 是肌动蛋白丝动力学的关键调节因子，可通过 LIM 激酶在 Ser-3 处磷酸化而失活，并通过称为 Slingshot (SSH) 的蛋白磷酸酶家族去磷酸化而重新激活。人类或小鼠基因组具有三个 Ssh 基因拷贝 (Ssh1-Ssh3)。先前的原位杂交分析揭示了每个小鼠 ssh 基因在神经元和非神经元组织中的特征表达模式。在这里，我们研究了单个基因产物的内源表达水平，并表明 Ssh-2 和 Ssh-3 的表达分别在神经和上皮组织中较高。为了探索 Ssh-3 在上皮组织中的作用，我们分离了 MDCK 细胞的衍生物，其中添加强力霉素后可以敲低 Ssh-3。因为我们在MDCK细胞中检测到了Ssh-1，所以我们进一步分离了Ssh-1和Ssh-3都被敲低的亚系，并一直在研究细胞形状的表型。为了检查 Ssh-3 在上皮形态发生中的体内作用，我们生成了 Ssh-3 敲除小鼠。 Ssh-3 敲除小鼠在两种不同的背景下均能存活且具有生育能力，我们一直在寻找各种上皮组织（例如乳腺和肾脏）的表型。