Regular Article
Rnd1, a Novel Rho Family GTPase, Induces the Formation of Neuritic Processes in PC12 Cells,☆☆

https://doi.org/10.1006/bbrc.2000.3842Get rights and content

Abstract

Rho family GTPases have been shown to be involved in the regulation of neuronal cell morphology, including neurite extension and retraction. Rho activation leads to neurite retraction and cell rounding, whereas Rac and Cdc42 are implicated in the promotion of filopodia and lamellipodia formation in growth cones and, therefore, in neurite extension. In this study, we examined the morphological role of Rnd1, a new member of Rho family GTPases, in PC12 cells, and found that expression of Rnd1 by itself caused the formation of many neuritic processes from the cell body with disruption of the cortical actin filaments, the processes having microtubules but few filamentous actin and neurofilaments. Treatment with cytochalasin D, an inhibitor of actin polymerization, could mimic the effects of expression of Rnd1, in that this inhibitor disrupted the cortical actin filaments and induced the formation of many thin processes containing microtubules. The process formation induced by Rnd1 was inhibited by dominant negative Rac1. These results suggest that Rnd1 induces the Rac-dependent neuritic process formation in part by disruption of the cortical actin filaments.

Cited by (35)

  • Interaction characteristics of Plexin-B1 with Rho family proteins

    2013, Biochemical and Biophysical Research Communications
    Citation Excerpt :

    An important question to be addressed is whether the displacement of Rac1 from B1RBD by Rnd1 releases Rac1 for signaling via other effectors or dislodges Rac1 from its signal transduction. A previous study by Negishi and coworkers demonstrated that Rac1 activity is required for the Rnd1-induced neurite formation and that Rac1 is an integral element of the signaling pathway downstream of Rnd1 [25]. One major interest of this study was to explore the selectivity of the interaction between B1RBD and Rho proteins.

  • Different requirement for Rnd GTPases of R-Ras GAP activity of Plexin-C1 and Plexin-D1

    2009, Journal of Biological Chemistry
    Citation Excerpt :

    Chimeric Plexin-B1/C1 encoding extracellular domain of Plexin-B1 (amino acids 1–1544) and cytoplasmic domain of Plexin-C1 (amino acids 1003–1575) was obtained by PCR. Hemagglutinin (HA)-tagged Rnd1, Rnd2, Rnd3, and green fluorescent protein (GFP)-tagged Rnd1, Rnd2, Rnd3, and R-Ras were obtained as described previously (19, 29). HA-tagged human R-Ras, GST-tagged Ras-binding domain of c-Raf-1 (RBD; amino acids 53–130), and Sema4D fused to human IgG1-Fc were obtained as described (25).

  • Rndl regulates axon extension by enhancing the microtubule destabilizing activity of SCG10

    2009, Journal of Biological Chemistry
    Citation Excerpt :

    Plasmids and Antibodies—GST-Rnd1, GST-Rnd2, GST-Rnd3, human GFP-Rnd1, and expression vectors for wild type and mutant forms of SCG10 were described previously (23, 25–27). The expression vector for Myc-tagged rat Rnd1 (14) was kindly provided by Dr. Negishi (Kyoto, Japan). To clone the vector for GST-SCG10-N38, oligonucleotides encoding amino acids 87–125 of SCG10 were cloned into pGEX-4T2.

View all citing articles on Scopus

Abbreviations used: F-actin, filamentous actin; HA, hemagglutinin; FITC, fluorescein isothiocyanate; EGFP, enhanced green fluorescent protein; DMEM, Dulbecco's modified Eagle medium; PCR, polymerase chain reaction; PBS, phosphate-buffered saline; NGF, nerve growth factor.

☆☆

This work was supported in part by Grants-in-Aid for Scientific Research from the Ministry of Education, Science, Sports, and Culture of Japan (10470482, 11780579, 12053244, 12210078), and grants from Uehara Memorial Foundation and Inamori Foundation. J. Aoki is the recipient of a research fellowship from the Japan Society for the Promotion of Science for Young Scientists.

2

To whom correspondence should be addressed. Fax: +81-75-753-7688. E-mail: [email protected].

View full text