Torsin-1A-interacting proteins 1 and 2 (TOIP 1/2), also known as LAP1 proteins (Lamina-associated polypeptide 1) are type 2 integral membrane proteins with a single membrane-spanning region of the inner nuclear membrane [1,2]. These proteins interact ...
Torsin-1A-interacting proteins 1 and 2 (TOIP 1/2), also known as LAP1 proteins (Lamina-associated polypeptide 1) are type 2 integral membrane proteins with a single membrane-spanning region of the inner nuclear membrane [1,2]. These proteins interact with and activate Torsin A, an AAA+ ATPase localised to the endoplasmic reticulum (ER) through a perinuclear domain and forms a heterohexameric (LAP1-Torsin)3 ring that targets Torsin to the nuclear envelope. LAP1 has an atypical AAA+ fold and provides an arginine finger to the Torsin A active site to promote its ATPase activity [3,4]. A single mutation in Torsin A causes early onset primary dystonia, a painful and severely disabling neuromuscular disease [3,4]. This entry represents the C-terminal AAA+ activator domain of LAP1.
This domain is found at the C-terminal end of Torsin-1A from humans (TOR1A), an AAA+ ATPase that resides in the endoplasmic reticulum and the contiguous perinuclear space primarily in nerve cells. TOR1A needs the AAA+-like proteins Lamina-associated ...
This domain is found at the C-terminal end of Torsin-1A from humans (TOR1A), an AAA+ ATPase that resides in the endoplasmic reticulum and the contiguous perinuclear space primarily in nerve cells. TOR1A needs the AAA+-like proteins Lamina-associated protein 1 (LAP1) or Luminal domain like LAP1 (LULL1) to catalyze ATP hydrolysis. A single amino acid deletion in the domain represented in this entry is known to be at the root of primary dystonia, probably by weakening these interactions. This small domain forms a three-helix bundle [1].
