Kidins220/ARMS regulates Rac1-dependent neurite outgrowth by direct interaction with the RhoGEF Trio

Abstract

SummaryNeurite extension depends on extracellular signals that lead to changes in gene expression and rearrangement of the actin cytoskeleton. A factor that might orchestrate these signalling pathways with cytoskeletal elements is the integral membrane protein Kidins220/ARMS, a downstream target of neurotrophins. Here, we identified Trio, a RhoGEF for Rac1, RhoG and RhoA, which is involved in neurite outgrowth and axon guidance, as a binding partner of Kidins220. This interaction is direct and occurs between the N-terminus of Trio and the ankyrin repeats of Kidins220. Trio and Kidins220 colocalise at the tips of neurites in NGF-differentiated PC12 cells, where F-actin and Rac1 also accumulate. Expression of the ankyrin repeats of Kidins220 in PC12 cells inhibits NGF-dependent and Trioinduced neurite outgrowth. Similar results are seen in primary hippocampal neurons. Our data indicate that Kidins220 might localise Trio to specific membrane sites and regulate its activity, leading to Rac1 activation and neurite outgrowth.

Tyrosine Phosphorylation of the Rho Guanine Nucleotide Exchange Factor Trio Regulates Netrin-1/DCC-Mediated Cortical Axon Outgrowth

“…Recombinant proteins corresponding to Trio fragments 1 to 8 were expressed in E. coli BL21(DE3) cells, except for fragment 2, which was expressed in E. coli Rosetta, and were purified as described previously (41). Briefly, 1 liter of log-phase bacteria was induced with 1 mM isopropylthiogalactopyranoside (IPTG) and shaken overnight at 22°C.…”

Cell surface dynamics – how Rho GTPases orchestrate the interplay between the plasma membrane and the cortical cytoskeleton

“…A crucial aspect of Rac1 and Cdc42 activity is their activationdependent accumulation at discrete sites in the plasma membrane. At these sites, they colocalize with other proteins, including their GEFs, for example TRIO (triple functional domain protein), VAV, DOCK1 (dedicator of cytokinesis 1) and PREX1 (for phosphatidylinositol 3,4,5-trisphosphate-dependent Rac exchanger 1) (see, among others, Premkumar et al, 2010;Neubrand et al, 2010;Tolias et al, 2011;Citi et al, 2011). As expected, downregulation of these GEFs results in the inhibition of Rac1-and/or Cdc42-dependent processes (Côté and Vuori, 2007).…”

ARMS/Kidins220 and synembryn-B levels regulate NGF-mediated secretion

“…ARMS has been directly linked to NGF-mediated signaling (Arévalo et al, 2006(Arévalo et al, , 2004Neubrand et al, 2010) and NGF elicits regulated secretion (Canossa et al, 1997;Kruttgen et al, 1998). To investigate the role of ARMS, we utilized PC12 cells because they respond to NGF (Greene and Tischler, 1976) and are a model widely used to study secretion (Westerink and Ewing, 2008).…”

“…In order to determine how ARMS and synembryn-B could modulate secretion, we took into account that NGF treatment leads to Rac1 activation (Nusser et al, 2002;Yamaguchi et al, 2001) and that ARMS has been shown to modulate Rac1 activation through the GEF Trio (Neubrand et al, 2010). Because Ric-8 regulates Trio through Gαq (Williams et al, 2007), we assessed whether ARMS and synembryn-B regulated Rac1 activity in response to NGF.…”

“…Among other functions, ARMS has been implicated in the sustained activation of ERK1/2 in response to NGF (Arévalo et al, 2006(Arévalo et al, , 2004Hisata et al, 2007;Neubrand et al, 2010), in synaptic modulation (Arévalo et al, 2010;Cesca et al, 2015;Cortés et al, 2007;LopezMenendez et al, 2009;Sutachan et al, 2010;Wu et al, 2009), in dendritic arborization Chen et al, 2012;Wu et al, 2009), in excitotoxicity (Lopez-Menendez et al, 2009), in tumor progression in melanoma cells (Liao et al, 2011), in T cell activation (Deswal et al, 2013) and in the regulation of B cell development (Fiala et al, 2015). In addition, ARMS has been implicated in the secretion of the neurotensin hormone in BON cells, a cell line derived from a human pancreatic carcinoid tumor, in response to phorbol esters located downstream of PKD (Li et al, 2008(Li et al, , 2012.…”