title: The role of lamin B1 for the maintenance of nuclear structure and function.
abstract: Lamins constitute an integral structural component of the nuclear lamina. However, their impact on the structure and stability of chromosome territories, and on the regulation of gene expression is explored to a lesser extent. By 3D-FISH, Camps and colleagues showed that lamin B1 (LMNB1) is required for proper chromosome condensation in interphase nuclei, and deficiency of LMNB1 triggers the relocation of the epigenetic mark of facultative heterochromatin, H3K27me3, toward the interior of the nucleus. Additionally, LMNB1 repression slowed cellular growth due to S-phase delays and increased genomic instability. Finally, silencing of LMNB1 resulted in enlarged nuclear speckles and in extensive changes in alternative splicing of multiple genes. Altogether, the data suggest a central role of LMNB1 for the condensation of chromosome territories, for the distribution of heterochromatin, and for the regulation of gene expression and splicing.
authors.affiliation: a Laboratory of Gastrointestinal and Pancreatic Oncology; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) ; Hospital Clínic of Barcelona, CIBERehd ; Barcelona , Spain.
authors.forename: Jordi
authors.initials: J
authors.lastname: Camps
authors.forename: Michael R
authors.initials: MR
authors.lastname: Erdos
authors.forename: Thomas
authors.initials: T
authors.lastname: Ried
mesh_terms: D021581:Active Transport, Cell Nucleus; D000818:Animals; D002875:Chromosomes / Q000378:metabolism*; D004261:DNA Replication; D005786:Gene Expression Regulation; D006801:Humans; D034921:Lamin Type B / Q000378:metabolism*; D034881:Nuclear Lamina / Q000378:metabolism*
chemical_list: D034921:Lamin Type B
keywords: B1; DNA replication; Lamin LMNB1; S-phase; alternative splicing; chromatin decondensation; chromosome territories; histone modifications; nuclear organization