TOR1AIP1
Developmental stage
Isoform 1
Expression increases during neuronal development (at protein level).
Isoform 4
Expression increases during neuronal development (at protein level).
Function
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.
Involvement in disease
Myopathy, autosomal recessive, with rigid spine and distal joint contractures
MRRSDC
An autosomal recessive degenerative myopathy characterized by muscle weakness initially involving the proximal lower limbs, followed by distal upper and lower limb muscle weakness and atrophy. Other features include joint contractures, rigid spine, and restricted pulmonary function. Cardiac involvement has been observed in some patients. Disease onset is in the first or second decades of life.
None
The disease is caused by variants affecting the gene represented in this entry.
Post-translational modifications
Phosphorylated. Dephosphorylated at Ser-309 and Ser-315 by serine/threonine-protein phosphatase PP1.
Sequence Similarities
Belongs to the TOR1AIP family.
Tissue Specificity
Expressed in muscle, liver and kidney.
Isoform 1
Major isoform present in liver, brain and heart (at protein level). Expressed at lower levels than isoform 4 in lung, kidney and spleen (at protein level). Similar levels of isoforms 1 and 4 are observed in ovary, testis and pancreas (at protein level).
Isoform 4
Expressed at higher levels than isoform 1 in lung, kidney and spleen (at protein level). Expressed at lower levels than isoform 1 in liver, brain and heart (at protein level). Similar levels of isoforms 1 and 4 are observed in ovary, testis and pancreas (at protein level).
Cellular localization
- Nucleus inner membrane
- Single-pass membrane protein
- Isoform 4
- Nucleus envelope
- Nucleus
- Found mainly in the nuclear envelope and also inside the nucleus.
Alternative names
LAP1, TOR1AIP1, Torsin-1A-interacting protein 1, Lamin-associated protein 1B, LAP1B