Dynamic RhoA-Mediated Remodeling of Ordered Membrane Domains

Abstract

The formation of ordered proteolipid membrane domains (OMDs) within the plasma membrane has emerged as a fundamental process that modifies membrane function, particularly in response to cell stresses that promote pathological states. Here, we identify a previously unrecognized role for the small GTPase RhoA to rapidly modulate OMDs, thereby linking cytoskeletal remodeling and membrane mechanics to OMD formation. Pharmacological and optogenetic manipulation of RhoA rapidly altered OMD dimensions in both human cell lines and dorsal root ganglion (DRG) nociceptors. The RhoA-dependent OMD expansion required actin remodeling, changes in membrane mechanical state, and protein palmitoylation. Furthermore, in a spared nerve injury (SNI) model of neuropathic pain associated with altered membrane mechanics, disrupted OMD organization, and neuronal hyperexcitability, RhoA activation promoted OMD remodeling and was accompanied by reduced HCN channel activity and action potential firing. These findings highlight alterations in plasma membrane physical properties, including changes in OMD organization, as key features of neuropathic stress. RhoA-driven OMD remodeling, mediated by diaphanous-related formin and Rho-associated kinase, may serve as a compensatory membrane adaptation that counteracts neuropathic hyperexcitability.