Oligodendrocytes are the myelinating cells of the central nervous system (CNS). The importance of myelination is illustrated by the neurological consequences caused by demyelination, the process or state resulting from the loss or destruction of myelin such as in multiple sclerosis (MS), the most frequent CNS chronic demyelinating disease. Failure of remyelination is thought to be the major cause of MS disease progression and may be caused by the incapacity of oligodendrocyte progenitor cells (OPC) to differentiate into myelin-competent oligodendrocytes. Rho GTPases regulate signaling pathways involved in actin cytoskeleton, microtubule dynamics, cell polarity, membrane trafficking and gene transcription. They are expressed by oligodendrocytes and are likely to be involved in some of the events leading to myelination, but their role in this process is still poorly investigated. Additionally, in the context of MS and remyelination, the modulation and/or activity of such molecules in oligodendrocytes has still not been addressed.Therefore, we intend to characterize the network of molecules associated with Rho GTPase signaling responsible for regulating oligodendrocyte cell spreading, process extension, and formation of the highly ramified processes typical of differentiating oligodendrocytes using proteomics and interference RNA-based functional assays in primary cultures and in axon-oligodendrocytes co-cultures. Additionally, we want to evaluate if and how the expression and activities of such molecules are affected by the inflammatory milieu, in vitro and in vivo using experimental autoimmune encephalomyelitis (EAE) animal models. This knowledge will allow us to gain valuable insight into the mechanisms that regulate the establishment and stabilization of oligodendrocyte-axon cell–cell interactions and how their impairment compromise remyelination in demyelinating diseases such as MS. Hopefully, this knowledge will help us to design better therapeutic strategies.