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LMNA
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功能
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核纤层是真核生物细胞核中附于内核膜内侧的网络片层结构。其核纤层蛋白家族在进化中高度保守。在有丝分裂过程中，核纤层蛋白磷酸化，核纤层解聚（这一过程是可逆的）。Lamin蛋白质被认为与细胞核的稳定性、染色质的结构与基因的表达有关. Vertebrate lamins consist of two types, A and B. Through alternate splicing, this gene encodes three type A lamin isoforms._NEWLINE_Early in mitosis, MPF phosphorylates specific serine residues in all three nuclear lamins, causing depolymerization of the lamin intermediate filaments. The phosphorylated lamin B dimers remain associated with the nuclear membrane via their isoprenyl anchor.  Lamin A is targeted to the nuclear membrane by an isoprenyl group but it is cleaved shortly after arriving at the membrane.  It stays associated with the membrane through protein-protein interactions of itself and other membrane associated proteins, such as LAP1.  Depolymerization of the nuclear lamins leads to disintegration of the nuclear envelope.  Transfection experiments demonstrate that phosphorylation of human lamin A is required for lamin depolymerization, and thus for disassembly of the nuclear envelope, which normally occurs early in mitosis.
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临床意义
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Mutations in the LMNA gene are associated with several diseases, including Emery-Dreifuss muscular dystrophy, familial partial lipodystrophy, limb girdle muscular dystrophy, dilated cardiomyopathy, Charcot-Marie-Tooth disease, Restrictive dermopathy and Hutchinson-Gilford progeria syndrome. A truncated version of lamin A, commonly known as progerin, causes Hutchinson-Gilford progeria syndrome.