Repulsive Guidance Molecule A (RGMA) is a member of the RGM family, which also includes RGMb (DRAGON) and RGMc (hemojuvelin). It is a glycosylphosphatidylinositol (GPI)-anchored protein characterized by a von Willebrand factor type D domain and a GPI-anchor, facilitating membrane association and soluble forms¹ ². This dual functional nature enables RGMA to act both as a localized, membrane-bound signal and as a long-range soluble signaling molecule, expanding its versatility in biological processes³.

RGMA plays a critical role in axonal guidance, neuronal differentiation, and survival, primarily by interacting with the receptor neogenin. This interaction also regulates apoptosis via Akt pathway dephosphorylation. RGMA acts as a Bone Morphogenetic Protein (BMP) co-receptor, enhancing Smad-dependent signaling pathways² ³. It is expressed in the central nervous system (CNS), particularly in retinal ganglion cells, midbrain dopaminergic neurons, and the spinal cord, with roles extending from embryonic development to adult neuroplasticity¹ ³ ⁴.

RGMA is implicated in several biological processes, including axonal regeneration and inhibition, neuronal survival, and inflammatory responses. Pathological upregulation of RGMA has been linked to neurodegenerative disorders like multiple sclerosis (MS) and Parkinson’s disease. In MS, RGMA inhibits axonal regeneration, while in Parkinson’s, it contributes to dopaminergic neuron degeneration¹ ⁴ ⁵. Research areas benefiting from RGMA immunodetection include neuroregeneration, CNS repair, and therapeutic strategies for neurodegenerative diseases⁴ ⁵.