GASP-1 Background Information GASP-1 (G-protein coupled receptor-associated sorting protein 1), also known as GPRASP1, is a 1395 amino acid member of the GPRASP protein family. In lysosomes, GASP-1 targets receptors for degredation and may also regulate lysosomal sorting and functional down-regulation of G-protein coupled receptors. Localized to the cytoplasm, GASP-1 interacts with the cytoplasmic tails of G-protein coupled receptors, such as D2DR, D4DR, ∫2-AR and DOR-1. GASP-1 has also been found to interact with Per1, a period protein that exhibits circadian rhythyms in the superchiasmatic nucleus (SCN) found in the brain. GASP-1 is expressed mainly in the brain, with lower expression in spinal chord, medulla and substantia nigra.
