Rho-ROCK signal pathway regulates microtubule-based process formation of cultured podocytes - Inhibition of ROCK promoted process elongation
Rho-ROCK signal pathway regulates microtubule-based process formation of cultured podocytes - Inhibition of ROCK promoted process elongation
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DOI：
10.1159/000078406
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发表时间：
2004-01-01
影响因子：
--
通讯作者：
Kobayashi, N
中科院分区：
文献类型：
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作者：
Gao, SY;Li, CY;Kobayashi, N
背景：足细胞是肾小球内脏上皮细胞，有两种突起，即含有微管的主突起(MTS)和含有肌动蛋白细丝的足突(AFS)。本研究探讨了足细胞形成过程中Rho-Rock信号转导通路是如何组织MT的。方法：条件永生化小鼠足细胞经诱导分化后，分别用ROCK的特异性抑制剂Y-27632、RhoA的外酶C3和抑制RhoA的Forsklin处理，以抑制Rho-ROCK通路。结果：岩石抑制显著促进了含MT束的粗突的形成。Y27632促进突起的形成，即使在存在破坏AFS的LATRUNC A的情况下，强烈表明ROCK直接调节MT组装。Y-27632处理提高了MT的稳定性，且稳定的MT优先定位于足突。此外，当Y-27632和Forsklin以及Y-27632和C3联合处理时，足细胞不仅形成基于MT的厚突起，而且还形成基于AF的薄突起。结论：这些数据表明MT组织中的岩石有助于促进足突的形成，尽管最初认为它调节房颤的组装。以房颤为基础的薄投射似乎主要是由抑制RhoA和ROCK诱导的。本研究揭示了Rho-Rock信号通路在足细胞形成过程中MTS和AFS重组中的重要作用。版权所有(C)2004 S.Karger AG，巴塞尔。
Background: Podocytes, renal glomerular visceral epithelial cells, have two kinds of processes, namely major processes containing microtubules (MTs) and foot processes with actin filaments (AFs). The present study investigated how MTs are organized by the Rho-ROCK signal transduction pathway during process formation of podocytes. Method: After induction of differentiation, podocytes of the conditionally immortalized mouse cell line were treated with Y-27632, a specific inhibitor of ROCK, and exoenzyme C3, an inhibitor of RhoA, as well as with forskolin whose effects include inhibition of RhoA, in order to inhibit the Rho-ROCK pathway. Results: Inhibition of ROCK significantly enhanced the formation of thick processes containing MT bundles. Y27632 promoted process formation even in the presence of latrunculin A which disrupts AFs, strongly suggesting that ROCK directly regulates MT assembly. Treatment with Y-27632 increased MT stability, and stabilized MTs preferentially localized in podocyte processes. Moreover, when treated with a combination of Y-27632 and forskolin, and with Y-27632 and C3 as well, podocytes developed not only MT-based thick processes but also AF-based thin projections. Conclusions: These data indicate a contribution of ROCK in MT organization to promote podocyte process formation, although it was originally thought to regulate AF assembly. AF-based thin projections seem to be induced mainly by inhibition of RhoA and ROCK. The present study reveals a significant role of the Rho-ROCK signal pathway in the reorganization of both MTs and AFs during process formation of podocytes. Copyright (C) 2004 S. Karger AG, Basel.