Lamin B1 (LMNB1)

Lamin B1 is a type V intermediate filament protein and a member of the lamin family that forms the nuclear lamina, a network underlying the inner nuclear membrane in metazoan cells. It serves crucial roles in maintaining nuclear shape, mechanical stability, and structural support, organizes chromatin and regulates genome function and gene expression, and is essential for proper cell cycle progression, DNA replication, and DNA repair. Lamin B1 is especially important for brain development and function: duplication of the LMNB1 gene causes autosomal dominant adult-onset demyelinating leukodystrophy, while deficiency leads to developmental deficits, including neural tube defects and abnormal neuronal dendrite morphology. Lamin B1 is anchored to the nuclear envelope and is permanently farnesylated, distinguishing it from A-type lamins, and it interacts with chromatin regions called lamin-associated domains (LADs) associated with gene repression. Altered Lamin B1 levels serve as biomarkers for cellular senescence, aging, and certain neuropathological states. Although it is critical for cell viability and genome organization, it is not currently considered a direct pharmacological target.

Other names

Lamin-B1LB1Nuclear lamin B1LMNB1