Signal transduction of Proteoglycan-type protein tyrosine phosphatase, PTPS.

蛋白聚糖型蛋白酪氨酸磷酸酶（PTPS）的信号转导。

• 批准号: 13680699
• 负责人: MAEDA Nobuaki
• 金额: $ 2.3万
• 依托单位: Tokyo Metropolitan Organization for Medical Research (2002)Okazaki National Research Institutes (2001)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13680699/
• 关键词: PTPζ; proteoglycan; pleiotrophin; midkine; Purkinje cell; chondroitin sulfate; コンドロイチン硫酸; 樹状突起; プレイオトロフィン(PTN); ミッドカイン(MK); プルキンエ細胞; PTPS; GIT; 脳; ヘパリン結合性成長因子

PTPζ is a receptor-type protein tyrosine phosphatase, which is abundantly expressed in the developing brain as a chondroitin sulfate proteoglycan. PTPζ binds with pleiotrophin and midkine with high affinity. The chondroitin sulfate portion of PTPζ plays essential roles in the binding to these growth factors. Removal of chondroitin sulfate chains from PTPζ by chondroitinase ABC digestion resulted in the marked decrease of the binding affinity to pleiotrophin and midkine and the loss of signal transduction. The fine structure of chondroitin sulfate chains of PTPζ regulates its binding to these growth factors. Chondroitin sulfate chains of PIPζ contain about 1% D-unit, which seems to be the essential structure for the high affinity binding to pleiotrophin and midkine.Immunohistochemical analysis of PTPζ, pleiotrophin and chondroitin sulfate D-unit demonstrated that the expression of these molecules are highly correlated with the dendrite formation of cerebellar Purkinje cells. So, we examined the roles of PTPζ in the morphogenesis of Purkinje cells using organotypic slice culture system of rat cerebellum. Abnormal Purkinje cells with disoriented and/or multiple primary dendrites markedly increased by the additions of (1)polyclonal antibodies against PTPζ, (2) sodium vanadate, a protein tyrosine phosphatase inhibitor, (3) chondroitinase ABC, (4)chondroitin sulfate D, and (5) pleiotrophin. These results suggest that pleiotrophin-PTPζ signaling regulates the morphogenesis of Purkinje cell dendrites.We also tried to identify the substrate molecules of PTPζ using the yeast substrate-trapping system. This method is based on the yeast two-hybrid system, with two modufucations : conditional expression of v-src to tyrosine phosphorylate the prey proteins and screening by using a substrate-trap mutant of PTPζ. By this system, we identified GIT1/Cat-1 as a substrate.

PTP 是一种受体型蛋白酪氨酸磷酸酶，在发育中的大脑中以硫酸软骨素蛋白聚糖的形式大量表达。 PTPδ 以高亲和力与多效蛋白和中期因子结合。 PTP z 的硫酸软骨素部分在与这些生长因子的结合中发挥着重要作用。通过软骨素酶 ABC 消化从 PTP z 中去除硫酸软骨素链，导致与多效素和中期因子的结合亲和力显着降低以及信号转导的丧失。 PTP 硫酸软骨素链的精细结构调节其与这些生长因子的结合。 PIPδ的硫酸软骨素链含有约1%的D-单元，这似乎是与多效素和中期因子高亲和力结合的必需结构。PTPδ、多效素和硫酸软骨素D-单元的免疫组织化学分析表明，这些分子的表达与小脑浦肯野细胞树突的形成高度相关。因此，我们使用大鼠小脑的器官切片培养系统检查了 PTPδ 在浦肯野细胞形态发生中的作用。通过添加 (1) 抗 PTP 多克隆抗体、(2) 钒酸钠（一种蛋白酪氨酸磷酸酶抑制剂）、(3) 软骨素酶 ABC、(4) 硫酸软骨素 D 和 (5) 多效素，具有迷失方向和/或多发初级树突的异常浦肯野细胞显着增加。这些结果表明，多效蛋白-PTP 信号传导调节浦肯野细胞树突的形态发生。我们还尝试使用酵母底物捕获系统来鉴定 PTP 的底物分子。该方法基于酵母双杂交系统，具有两种修饰：条件表达 v-src 以使猎物蛋白酪氨酸磷酸化，并使用 PTP 的底物捕获突变体进行筛选。通过该系统，我们确定 GIT1/Cat-1 为底物。

项目成果

Tanaka, M., Maeda, N.et al.: "A chondroitin sulfate proteoglycan PTPζ/RPTP β regulates the morphogenesis of purkinje cell dendrites in the developing cerebellum"Journal of Neuroscience. (in press). (2003)

Tanaka, M., Maeda, N. 等人：“硫酸软骨素蛋白聚糖 PTP z/RPTP β 调节发育中小脑中浦肯野细胞树突的形态发生”《神经科学杂志》（2003 年出版）。

前田信明: "PTPζのシグナル伝達機構と脳の形態形成"細胞工学. 20. 1107-1113 (2001)

Nobuaki Maeda：“PTPζ信号转导机制和大脑形态发生”《细胞工程》20。1107-1113（2001）。

Kawachi, H. et al.: "Identification of GIT1/Cat-1 as substrate molecule of protein tyrosine phosphates ζ/β by the yeast substrate-trapping system"Proc. Natl. Acad. Sci. USA. 98. 6593-6598 (2001)

Kawachi, H. 等人：“通过酵母底物捕获系统鉴定 GIT1/Cat-1 作为蛋白质酪氨酸磷酸盐的底物分子”，Proc. Acad. 98. 6593-6598。 2001）

Qi, M.et al.: "Haptotactic migration induced by midkine: Involvement of protein-tyrosine phosphatase, mitogen-activated protein kinase and phosphatidylinositol 3-kinase"J. Biol. Chem.. 276. 15868-15875 (2001)

Qi, M.等：“中期因子诱导的触触迁移：蛋白酪氨酸磷酸酶、丝裂原激活蛋白激酶和磷脂酰肌醇 3-激酶的参与”J.

Kawachi, H., Fujikawa, A., Maeda, N., Noda, M.: "Identification of GITl/Cat 1 as a substrate molecule of protein tyrosid phosrphatase ζ/β by yeast substrate-trapping system"Proc Natl, Acad. Sci. USA. 98(12). 6593-6598 (2001)

Kawachi，H.，Fujikawa，A.，Maeda，N.，Noda，M.：“通过酵母底物捕获系统鉴定 GIT1/Cat 1 作为蛋白酪氨酸磷酸酶 z/β 的底物分子”Proc Natl，Acad。科学。98(12)。