Signal-induced proliferation-associated 1-like protein 2 (SIPA1L2)

Signal-induced proliferation-associated 1-like protein 2 (SIPA1L2) is a cytosolic regulatory protein with RapGAP activity, meaning it promotes the inactivation of the small GTPases Rap1 and Rap2 through stimulation of their intrinsic GTPase activities[2][3]. SIPA1L2 contains a GTPase-activating domain, a PDZ domain, and a coiled-coil domain featuring a leucine zipper[2]. Most abundantly expressed in granule cells of the hippocampus and cerebellum, SIPA1L2 is critical for retrograde trafficking and local signaling of the BDNF/TrkB receptor complex, essential for synaptic plasticity including long-term potentiation[3]. SIPA1L2 directly binds TrkB, Snapin, and LC3, forming complexes necessary for proper neuronal transport and signaling at synapses[3][4]. Mutations or loss of function in SIPA1L2 have been implicated in rare neurodevelopmental and neurodegenerative diseases[2][3]. If any new data emerges regarding direct pharmacological modulation or expanded roles in disease, molecular classification may be updated but as of now, SIPA1L2 is considered a signaling enzyme/regulator, not a direct drug target.

Other names

SPAR2SPAL2KIAA1389SIPA1-like protein 2SPA-1-like 2Spine-associated RapGAP 2Signal induced proliferation associated 1 like 2SIPA1L2

Not applicable; since no drugs directly target SIPA1L2, mechanisms of action are not established