LMNB1
Function
Lamins are intermediate filament proteins that assemble into a filamentous meshwork, and which constitute the major components of the nuclear lamina, a fibrous layer on the nucleoplasmic side of the inner nuclear membrane (PubMed:28716252, PubMed:32910914). Lamins provide a framework for the nuclear envelope, bridging the nuclear envelope and chromatin, thereby playing an important role in nuclear assembly, chromatin organization, nuclear membrane and telomere dynamics (PubMed:28716252, PubMed:32910914). The structural integrity of the lamina is strictly controlled by the cell cycle, as seen by the disintegration and formation of the nuclear envelope in prophase and telophase, respectively (PubMed:28716252, PubMed:32910914).
Involvement in disease
Leukodystrophy, demyelinating, autosomal dominant, adult-onset
ADLD
A slowly progressive and fatal demyelinating leukodystrophy, presenting in the fourth or fifth decade of life. Clinically characterized by early autonomic abnormalities, pyramidal and cerebellar dysfunction, and symmetric demyelination of the CNS. It differs from multiple sclerosis and other demyelinating disorders in that neuropathology shows preservation of oligodendroglia in the presence of subtotal demyelination and lack of astrogliosis.
None
The disease is caused by variants affecting the gene represented in this entry.
Microcephaly 26, primary, autosomal dominant
MCPH26
A form of microcephaly, a disease defined as a head circumference more than 3 standard deviations below the age, sex and ethnically matched mean. Brain weight is markedly reduced and the cerebral cortex is disproportionately small. MCPH26 is an autosomal dominant, progressive form apparent at birth or in early infancy. It is associated with relative short stature, variable severity of intellectual disability, and neurological features as the core symptoms. Brain imaging shows a simplified gyral pattern of the cortex and abnormal corpus callosum in some patients.
None
The disease is caused by variants affecting the gene represented in this entry.
Post-translational modifications
B-type lamins undergo a series of modifications, such as farnesylation and phosphorylation. Increased phosphorylation of the lamins occurs before envelope disintegration and probably plays a role in regulating lamin associations.
Phosphorylation plays a key role in lamin organization, subcellular localization and nuclear envelope disintegration. Phosphorylation by CDK1 at Ser-23 and Ser-393 at the onset of mitosis drives lamin disassembly and nuclear envelope breakdown.
Sequence Similarities
Belongs to the intermediate filament family.
Cellular localization
- Nucleus lamina
Alternative names
LMN2, LMNB, LMNB1, Lamin-B1