Domain organization of human chromosomes revealed by mapping of nuclear lamina interactions.
The architecture of human chromosomes in interphase nuclei is still largely unknown. Microscopy studies have indicated that specific regions of chromosomes are located in close proximity to the nuclear lamina (NL). This has led to the idea that certain genomic elements may be attached to the NL, which may contribute to the spatial organization of chromosomes inside the nucleus. However, sequences in the human genome that interact with the NL in vivo have not been identified. Here we construct a high-resolution map of the interaction sites of the entire genome with NL components in human fibroblasts. This map shows that genome-lamina interactions occur through more than 1,300 sharply defined large domains 0.1-10 megabases in size. These lamina-associated domains (LADs) are typified by low gene-expression levels, indicating that LADs represent a repressive chromatin environment. The borders of LADs are demarcated by the insulator protein CTCF, by promoters that are oriented away from LADs, or by CpG islands, suggesting possible mechanisms of LAD confinement. Taken together, these results demonstrate that the human genome is divided into large, discrete domains that are units of chromosome organization within the nucleus.
Guelen
Lars
L
Division of Molecular Biology, Netherlands Cancer Institute, Plesmanlaan 121, Amsterdam, The Netherlands.
Pagie
Ludo
L
Brasset
Emilie
E
Meuleman
Wouter
W
Faza
Marius B
MB
Talhout
Wendy
W
Eussen
Bert H
BH
de Klein
Annelies
A
Wessels
Lodewyk
L
de Laat
Wouter
W
van Steensel
Bas
B
D000076246:CCCTC-Binding Factor; D002460:Cell Line; D002843:Chromatin / Q000235:genetics / Q000378:metabolism; D045584:Chromosome Positioning; D002877:Chromosomes, Human / Q000235:genetics / Q000378:metabolism*; D018899:CpG Islands / Q000235:genetics; D004268:DNA-Binding Proteins / Q000378:metabolism; D005347:Fibroblasts; D015894:Genome, Human; D006801:Humans; D034921:Lamin Type B / Q000378:metabolism; D034881:Nuclear Lamina / Q000737:chemistry / Q000378:metabolism*; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding; D012097:Repressor Proteins / Q000378:metabolism
D000076246:CCCTC-Binding Factor; C000619697:CTCF protein, human; D002843:Chromatin; D004268:DNA-Binding Proteins; D034921:Lamin Type B; D012097:Repressor Proteins