Journal Mobile Options
Table of Contents
Vol. 97, No. 2, 2004
Issue release date: June 2004
Nephron Exp Nephrol 2004;97:e49–e61

Rho-ROCK Signal Pathway Regulates Microtubule-Based Process Formation of Cultured Podocytes – Inhibition of ROCK Promoted Process Elongation

Gao S.-Y. · Li C.-Y. · Chen J. · Pan L. · Saito S. · Terashita T. · Saito K. · Miyawaki K. · Shigemoto K. · Mominoki K. · Matsuda S. · Kobayashi N.
Department of aAnatomy and Embryology, bDepartment of Hygiene, School of Medicine, and cDepartment of Biological Resources, Integrated Center for Science, Ehime University, Ehime, Japan

Individual Users: Register with Karger Login Information

Please create your User ID & Password

Contact Information

I have read the Karger Terms and Conditions and agree.

To view the fulltext, please log in

To view the pdf, please log in


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. Y-27632 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 / Drug Dosage

Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher or, in the case of photocopying, direct payment of a specified fee to the Copyright Clearance Center.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in goverment regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.


  1. Kriz W, Kobayashi N, Elger M: New aspects of podocyte structure, function and pathology. Clin Exp Nephrol 1998;2:85–99.
  2. Pavenstadt H, Kriz W, Kretzler M: Cell biology of the glomerular podocyte. Physiol Rev 2003;83:253–307.
  3. Mundel P, Shankland SJ: Podocyte biology and response to injury. J Am Soc Nephrol 2002;13:3005–3015.
  4. Kreidberg JA: Podocyte differentiation and glomerulogenesis. J Am Soc Nephrol 2003;14:806–814.
  5. Kobayashi N, Mundel P: A role of microtubules during the formation of cell processes in neuronal and non-neuronal cells. Cell Tissue Res 1998;291:163–174.
  6. Kobayashi N: Mechanism of the process formation: Podocytes versus neurons. Microsc Res Tech 2002;57:217–223.
  7. Ichimura K, Kurihara H, Sakai T: Actin filament organization of foot processes in rat podocytes. J Histochem Cytochem 2003;51:1589–1600.
  8. Mundel P, Reiser J, Zuniga Mejia Borja A, Pavenstadt H, Davidson GR, Kriz W, Zeller R: Rearrangements of the cytoskeleton and cell contacts induce process formation during differentiation of conditionally immortalized mouse podocyte cell lines. Exp Cell Res 1997;236:248–258.
  9. Kobayashi N, Reiser J, Kriz W, Kuriyama R, Mundel P: Nonuniform microtubular polarity established by CHO1/MKLP1 motor protein is necessary for process formation of podocytes. J Cell Biol 1998;143:1961–1970.
  10. Kobayashi N, Mominoki K, Wakisaka H, Shimazaki Y, Matsuda S: Morphogenetic activity of extracellular matrices on cultured podocytes. Laminin accelerates podocyte process formation in vitro. Ital J Anat Embryol 2001;106(suppl 1):423–430.
  11. Takai Y, Sasaki T, Matozaki T: Small GTP-binding proteins. Physiol Rev 2001;81:153–207.
  12. Etienne-Manneville S, Hall A: Rho GTPases in cell biology. Nature 2002;420:629–635.
  13. Hirose M, Ishizaki T, Watanabe N, Uehata M, Kranenburg O, Moolenaar WH, Matsumura F, Maekawa M, Bito H, Narumiya S: Molecular dissection of the Rho-associated protein kinase (p160ROCK)-regulated neurite remodeling in neuroblastoma N1E-115 cells. J Cell Biol 1998;141:1625–1636.
  14. Scaife RM, Job D, Langdon WY: Rapid microtubule-dependent induction of neurite-like extensions in NIH 3T3 fibroblasts by inhibition of ROCK and Cbl. Mol Biol Cell 2003;14:4605–4617.
  15. Yuan XB, Jin M, Xu X, Song YQ, Wu CP, Poo MM, Duan S: Signalling and crosstalk of Rho GTPases in mediating axon guidance. Nat Cell Biol. 2003;5:1–8.
  16. Andrews PM: The effect of vinblastine-induced microtubule loss on kidney podocyte morphology. Am J Anat 1977;150:53–61.
  17. Kobayashi N, Reiser J, Schwarz K, Sakai T, Kriz W, Mundel P: Process formation of podocytes: Morphogenetic activity of microtubules and regulation by protein serine/threonine phosphatase PP2A. Histochem Cell Biol 2001;115:255–266.
  18. Mundel P, Heid HW, Mundel TM, Kruger M, Reiser J, Kriz W: Synaptopodin: An actin-associated protein in telencephalic dendrites and renal podocytes. J Cell Biol 1997;139:193–204.
  19. Uehata M, Ishizaki T, Satoh H, Ono T, Kawahara T, Morishita T, Tamakawa H, Yamagami K, Inui J, Maekawa M, Narumiya S: Calcium sensitization of smooth muscle mediated by a Rho-associated protein kinase in hypertension. Nature 1997;389:990–994.
  20. Morii N, Narumiya S: Preparation of native and recombinant Clostridium botulinum C3 ADP-ribosyltransferase and identification of Rho proteins by ADP ribosylation. Methods Enzymol 1995;256:196–206.
  21. Endlich N, Endlich K: cAMP Pathway in podocytes. Microsc Res Tech 2002;57:228–231.
  22. Dong JM, Leung T, Manser E, Lim L: cAMP-induced morphological changes are counteracted by the activated RhoA small GTPase and the Rho kinase ROKα. J Biol Chem 1998;273:22554–22562.
  23. Ellerbroek SM, Wennerberg K, Burridge K: Serine phosphorylation negatively regulates RhoA in vivo. J Biol Chem 2003;278:19023–19031.
  24. Wessel D, Fluegge UI: A method for the quantitative recovery of proteins in dilute solution in the presence of detergents and lipids. Anal Biochem 1984;138:141–143.
  25. Katoh K, Kano Y, Amano M, Kaibuchi K, Fujiwara K: Stress fiber organization regulated by MLCK and Rho-kinase in cultured human fibroblasts. Am J Physiol 2001;280:C1669–C1679.
  26. Edson K, Weisshaar B, Matus A: Actin depolymerization induces process formation on MAP2-transfected non-neuronal cells. Development 1993;117:689–700.
  27. Westermann S, Weber K: Post-translational modifications regulate microtubule function. Nat Rev Mol Cell Biol 2003;4:938–947.
  28. Kobayashi N, Shimazaki Y, Wakisaka H, Saito S, Mominoki K, Matsuda S, Mundel P: Inhibition of Rho small GTPase induces actin-based projections of cultured podocytes (abstract). J Am Soc Nephrol 2000;11:378A.
  29. Wong WT, Faulkner-Jones BE, Sanes JR, Wong RO: Rapid dendritic remodeling in the developing retina: Dependence on neurotransmission and reciprocal regulation by Rac and Rho. J Neurosci 2000;20:5024–5036.
  30. Leemhuis J, Boutillier S, Barth H, Feuerstein TJ, Brock C, Nuernberg B, Aktories K, Meyer DK: Rho GTPases and phosphoinositide 3-kinase organize formation of branched dendrites. J Biol Chem 2004;279:585–596 (Epub Oct 24, 2003).
  31. Everett AD, Xue C, Stoops T: Developmental expression of protein phosphatase 2A in the kidney. J Am Soc Nephrol 1999;10:1737–1745.
  32. Svennilson J, Sandberg-Nordqvist A, Aperia A: Age-dependent expression of protein phosphatase 2A in the developing rat kidney. Pediatr Nephrol 1999;13:800–805.
  33. Sayas CL, Moreno-Flores MT, Avila J, Wandosell F: The neurite retraction induced by lysophosphatidic acid increases Alzheimer’s disease-like tau phosphorylation. J Biol Chem 1999;274:37046–37052.
  34. Kobayashi N, Heid H, Sakai T, Kriz W, Mundel P: Molecular characterization reveals the identity of microtubule associated proteins MAP3 and MAP4. Biochem Biophys Res Commun 2000;268:306–309.
  35. Hida M, Fujita H, Omori S, Awazu M: Expression and role of RhoA/ROCK in renal development (abstract). J Am Soc Nephrol 2002;13:100.
  36. Shirato I, Sakai T, Kimura K, Tomino Y, Kriz W: Cytoskeletal changes in podocytes associated with foot process effacement in Masugi nephritis. Am J Pathol 1996;148:1283–1296.
  37. Togawa A, Miyoshi J, Ishizaki H, Tanaka M, Takakura A, Nishioka H, Yoshida H, Doi T, Mizoguchi A, Matsuura N, Niho Y, Nishimune Y, Nishikawa Si, Takai Y: Progressive impairment of kidneys and reproductive organs in mice lacking Rho GDIα. Oncogene 1999;18:5373–5380.
  38. Scott EK, Reuter JE, Luo L: Small GTPase Cdc42 is required for multiple aspects of dendritic morphogenesis. J Neurosci 2003;23:3118–3123.

Pay-per-View Options
Direct payment This item at the regular price: USD 38.00
Payment from account With a Karger Pay-per-View account (down payment USD 150) you profit from a special rate for this and other single items.
This item at the discounted price: USD 26.50