Alternative titles; symbols
HGNC Approved Gene Symbol: TOR1AIP2
Cytogenetic location: 1q25.2 Genomic coordinates (GRCh38) : 1:179,839,976-179,877,803 (from NCBI)
By searching a database for sequences similar to LAP1 (TOR1AIP1; 614512), Goodchild and Dauer (2005) identified TOR1AIP2, which they called LULL1. The deduced 473-amino acid protein has a transmembrane domain. Transfected baby hamster kidney (BHK) cells and HeLa cells expressed mouse Lull1 in the endoplasmic reticulum (ER). RT-PCR analysis revealed variable expression of Lull1 in all mouse tissues examined.
Goodchild and Dauer (2005) found that mouse torsin-1A (TOR1A; 605204) interacted with both Lap1 and Lull1 in transfected BHK cells. An ATPase-dead torsin-1A mutant and torsin-1A with a glutamate deletion (605204.0001) associated with early-onset torsion dystonia (DYT1; 128100) showed enhanced interaction with Lap1 and Lull1. Mutation analysis revealed that the C-terminal domain of Lap1 or Lull1 was required for interaction with torsin-1A.
Vander Heyden et al. (2009) found that overexpression of LULL1 in human osteosarcoma cells caused redistribution of TOR1A and a smaller portion of LULL1 from the ER to the nuclear envelope. Accumulation of TOR1A at the nuclear envelope caused displacement of SUN2 (613569), nesprin-2 (SYNE2; 608442), and nesprin-3 (610861), but not SUN1 (607723), from the nuclear envelope. LULL1 also caused redistribution of TOR1A with the dystonia-associated glutamate deletion to the nuclear envelope, but mutant TOR1A was less efficient in displacing SUN2. Mutation analysis revealed that the N terminus of TOR1A was required for interaction of TOR1A with LULL1.
By genomic sequence analysis, Goodchild and Dauer (2005) mapped the TOR1AIP2 gene to chromosome 1q24, adjacent to the TOR1AIP1 gene. These genes appeared to have arisen from a gene duplication event.
Goodchild, R. E., Dauer, W. T. The AAA+ protein torsinA interacts with a conserved domain present in LAP1 and a novel ER protein. J. Cell Biol. 168: 855-862, 2005. [PubMed: 15767459] [Full Text: https://doi.org/10.1083/jcb.200411026]
Vander Heyden, A. B., Naismith, T. V., Snapp, E. L., Hodzic, D., Hanson, P. I. LULL1 retargets torsinA to the nuclear envelope revealing an activity that is impaired by the DYT1 dystonia mutation. Molec. Biol. Cell 20: 2661-2672, 2009. [PubMed: 19339278] [Full Text: https://doi.org/10.1091/mbc.e09-01-0094]