to have some regulative part in the replication process. DNA repair Repair of DNA double-strand breaks can occur by either of two processes, non-homologous end joining (NHEJ) or homologous recombination (HR). A-type lamins promote genetic stability by maintaining levels of proteins that have key roles in NHEJ and HR. Mouse cells deficient for maturation of prelamin A show increased DNA damage and chromosome aberrations and are more sensitive to DNA damaging agents. Apoptosis Apoptosis is a form of programmed cell death that is critical in tissue homeostasis, and in defending the organism against invasive entry of pathogens. Apoptosis is a highly regulated process in which the nuclear lamina is disassembled in an early stage. In contrast to the phosphorylation-induced disassembly during mitosis, the nuclear lamina is degraded by proteolytic cleavage, and both the lamins and the nuclear lamin-associated membrane proteins are targeted. This proteolytic activity is performed by members of the caspase-protein family who cleave the lamins after aspartic acid (Asp) residues. Laminopathies Defects in the genes encoding for nuclear lamin (such as lamin A and lamin B1) have been implicated in a variety of diseases (laminopathies) such as: Emery–Dreifuss muscular dystrophy - A muscle wasting disease Progeria - Premature aging Restrictive dermopathy - A disease associated with extremely tight skin and other severe neonatal abnormalities References Ayelet Margalit, Sylvia Vlcek, Yozef Gruenbaum, Roland Foisner (2005). Breaking and Making of the Nuclear Envelope. Journal of Cellular Biochemistry 95, 454-465 Bruce Alberts, et al. Molecular Biology of the Cell (4th edition). Garland Science 676-677 Geoffrey M. Cooper, Robert E. Hausman. The Cell, A Molecular Approach (4th edition). Sinauer Associates 356-360 Goldman et al.(2002). "Nuclear lamins: building blocks of nuclear architecture". Genes and Development 16,533-547 Joanna M. Bridger, Nicole Foeger, Ian R. Kill, Harald Herrmann (2007). The Nuclear Lamina: both a structural framework and a platform for genome organization. FEBS Journal 274, 1354–1361 Nico Stuurman, Susanne Heins, Ueli Aebi (1998). Nuclear Lamins: Their Structure, Assembly and Interactions. Journal of Structural Biology 122, 42-46 Tripathi K, Muralikrishna B and Parnaik VK (2009) Differential dynamics and stability of lamin A rod domain mutants IJIB, 5(1), 1-8 Yozef Gruenbaum, Katherine L. Wilson, Amnon Harel, Michal Goldberg, Merav Cohen (2000). Nuclear Lamins – Structural Proteins with fundamental functions. Journal of Structural Biology 129, 313-323 External links Cell biology