4tvs
LAP1(aa356-583), H.sapiens, bound to VHH-BS1
Structural highlights
FunctionTOIP1_HUMAN Required for nuclear membrane integrity. Induces TOR1A and TOR1B ATPase activity and is required for their location on the nuclear membrane. Binds to A- and B-type lamins. Possible role in membrane attachment and assembly of the nuclear lamina.[1] Publication Abstract from PubMedLamin-associated polypeptide 1 (LAP1) resides at the nuclear envelope and interacts with Torsins, poorly understood ER-localized AAA+ ATPases, through a conserved, perinuclear domain. We determined the crystal structure of the perinuclear domain of human LAP1. LAP1 possesses an atypical AAA+ fold. While LAP1 lacks canonical nucleotide binding motifs, its strictly conserved arginine 563 is positioned exactly where the arginine finger of canonical AAA+ ATPases is found. Based on modeling and electronmicroscopic analysis we propose that LAP1 targets Torsin to the nuclear envelope by forming an alternating, heterohexameric (LAP1-Torsin)3 ring, in which LAP1 acts as the Torsin activator. The experimental data shows that mutation of arginine 563 in LAP1 reduces its ability to stimulate TorsinA ATPase hydrolysis. This knowledge may help understand the etiology of DYT1 primary dystonia, a movement disorder caused by a single glutamate deletion in TorsinA. How lamina-associated polypeptide 1 (LAP1) activates Torsin.,Sosa BA, Demircioglu FE, Chen JZ, Ingram J, Ploegh H, Schwartz TU Elife. 2014 Aug 22:e03239. doi: 10.7554/eLife.03239. PMID:25149450[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
| ||||||||||||||||||||
