Thioredoxin Mediates Oxidation-Dependent Phosphorylation of CRMP2 and Growth Cone Collapse

Abstract

Semaphorin3A (Sema3A) is a repulsive guidance molecule for axons, which acts by inducing growth cone collapse through phosphorylation of CRMP2 (collapsin response mediator protein 2). Here, we show a role for CRMP2 oxidation and thioredoxin (TRX) in the regulation of CRMP2 phosphorylation and growth cone collapse. Sema3A stimulation generated hydrogen peroxide (H2O2) through MICAL (molecule interacting with CasL) and oxidized CRMP2, enabling it to form a disulfide-linked homodimer through cysteine-504. Oxidized CRMP2 then formed a transient disulfide-linked complex with TRX, which stimulated CRMP2 phosphorylation by glycogen synthase kinase-3, leading to growth cone collapse. We also reconstituted oxidation-dependent phosphorylation of CRMP2 in vitro, using a limited set of purified proteins. Our results not only clarify the importance of H2O2 and CRMP2 oxidation in Sema3A-induced growth cone collapse but also indicate an unappreciated role for TRX in linking CRMP2 oxidation to phosphorylation.

MICAL1 facilitates breast cancer cell proliferation via ROS‐sensitive ERK/cyclin D pathway

“…MICAL proteins may oxidize actin at methionine residues directly, causing depolymerization of actin filaments 8. Microtubule assembly can also be altered indirectly by the ROS produced by MICAL 29. Oxidative stress originates from an imbalance between the generation and scavenging of ROS, activates aberrant signalling cascades and leads to tumorigenesis.…”

Identification of a Dithiol-disulfide Switch in Collapsin Response Mediator Protein 2 (CRMP2) That Is Toggled in a Model of Neuronal Differentiation

“…It was proposed that the phosphorylation state of CRMP2 may be redox regulated by formation of a mixed disulfide of CRMP2 with the N-terminal active site cysteinyl residue of Trx1, which was supposed to facilitate neuronal growth cone collapse (18). The evidence presented for this hypothesis was primarily deduced from an active site mutant of Trx1 and some faint Western blot bands.…”

“…[15][16][17]. Phosphorylation was suggested to be facilitated by interaction of CRMP2 with thioredoxin 1 (Trx1), in a redox-dependent mechanism (18).…”

Emerging roles of MICAL family proteins – from actin oxidation to membrane trafficking during cytokinesis

“…Several mechanisms have been proposed to explain how MICALs induce F-actin disassembly. As a monooxygenase enzyme, MICALs produce reactive oxygen species (ROS), such as H 2 O 2 , in vitro and in vivo (Giridharan and Caplan, 2014;Morinaka et al, 2011;Nadella et al, 2005;Zhou et al, 2011). In vitro experiments show that ROS molecules can modify cysteine, methionine and tryptophan residues of actin, which affects actin polymerization and depolymerization (Fedorova et al, 2010;Milzani et al, 2000;Nadella et al, 2005).…”

“…2). For example, MICAL proteins are required for several aspects of neuronal biology (Beuchle et al, 2007;Bron et al, 2007;Hung et al, 2013Hung et al, , 2010Kirilly et al, 2009;Lundquist et al, 2014;Luo et al, 2011;Morinaka et al, 2011;Pasterkamp et al, 2006;Schmidt et al, 2008;Terman et al, 2002;Van Battum et al, 2014), cell viability (Ashida et al, 2006;Loria et al, 2015;Zhou et al, 2011), cancer (Deng et al, 2016;Loria et al, 2015;Mariotti et al, 2016), immunity (Lee et al, 2013), skeletal muscle morphology and function (Beuchle et al, 2007;Hung et al, 2013), cardiovascular integrity , bristle development (Hung et al, 2011(Hung et al, , 2013, cell shape (Aggarwal et al, 2015;Giridharan et al, 2012b), membrane trafficking (Bachmann-Gagescu et al, 2015;Grigoriev et al, 2011) and regulation of nuclear actin (Lundquist et al, 2014). The newly described roles of MICAL family members in cytokinesis will be discussed in detail below.…”