Lamins are components of the nuclear lamina, a fibrous layer on the nucleoplasmic side of the inner nuclear membrane, which is thought to provide a framework for the nuclear envelope and may also interact with chromatin. Lamin A and C are present in equal amounts in the lamina of mammals. Plays an important role in nuclear assembly, chromatin organization, nuclear membrane and telomere dynamics. Required for normal development of peripheral nervous system and skeletal muscle and for muscle satellite cell proliferation. Required for osteoblastogenesis and bone formation. Also prevents fat infiltration of muscle and bone marrow, helping to maintain the volume and strength of skeletal muscle and bone. Required for cardiac homeostasis. Prelamin-A/C can accelerate smooth muscle cell senescence. It acts to disrupt mitosis and induce DNA damage in vascular smooth muscle cells (VSMCs), leading to mitotic failure, genomic instability, and premature senescence. Belongs to the intermediate filament family. In the arteries, prelamin-A/C accumulation is not observed in young healthy vessels but is prevalent in medial vascular smooth muscle cells (VSMCs) from aged individuals and in atherosclerotic lesions, where it often colocalizes with senescent and degenerate VSMCs. Prelamin-A/C expression increases with age and disease. In normal aging, the accumulation of prelamin-A/C is caused in part by the down-regulation of ZMPSTE24/FACE1 in response to oxidative stress. 4 alternatively spliced human isoforms have been reported. Note: This description may include information from UniProtKB.
Molecular Function: protein binding; structural molecule activity
Biological Process: cellular response to hypoxia; establishment or maintenance of microtubule cytoskeleton polarity; IRE1-mediated unfolded protein response; mitotic nuclear envelope reassembly; negative regulation of cardiac muscle hypertrophy in response to stress; negative regulation of cell proliferation; negative regulation of extrinsic apoptotic signaling pathway; negative regulation of mesenchymal cell proliferation; negative regulation of release of cytochrome c from mitochondria; positive regulation of cell aging; positive regulation of gene expression; positive regulation of histone H3-K9 trimethylation; protein import into nucleus; protein localization to nucleus; regulation of cell migration; regulation of protein localization to nucleus; regulation of protein stability; ventricular cardiac muscle cell development