CRABP1 (cellular retinoic acid binding protein 1) is a cytosolic protein that mediates both canonical and non-canonical activities of retinoic acid (RA). The protein's primary function involves regulating cellular responses to RA through the formation of specialized protein complexes called "CRABP1 signalosomes" 1. CRABP1 binds RA with high affinity and forms distinct signaling complexes including CRABP1-MAPK and CRABP1-CaMKII, which mediate rapid, non-genomic effects independent of nuclear RA receptors 23. These signalosomes regulate diverse cellular processes including stem cell proliferation, neuronal function, and cardiac health 2. In the nervous system, CRABP1-expressing neurons in the arcuate nucleus play crucial roles in energy homeostasis regulation, with ablation leading to obesity and diabetic phenotypes in mice 4. The protein also modulates exosome secretion through interactions with actin cytoskeletal dynamics and kinase signaling pathways 5. Clinically, CRABP1 dysfunction is implicated in neurodegenerative diseases, with reduced expression observed in ALS and SMA patient motor neurons 1. Additionally, polymorphisms in genes involved in RA metabolism, including those affecting CRABP1 pathways, may influence neural tube defect risk 6. The protein represents a therapeutic target for neurodegeneration management through CRABP1-selective compounds that avoid RAR-mediated toxicity 1.