Propagation of centromeric chromatin requires exit from mitosis.
Centromeres direct chromosomal inheritance by nucleating assembly of the kinetochore, a large multiprotein complex required for microtubule attachment during mitosis. Centromere identity in humans is epigenetically determined, with no DNA sequence either necessary or sufficient. A prime candidate for the epigenetic mark is assembly into centromeric chromatin of centromere protein A (CENP-A), a histone H3 variant found only at functional centromeres. A new covalent fluorescent pulse-chase labeling approach using SNAP tagging has now been developed and is used to demonstrate that CENP-A bound to a mature centromere is quantitatively and equally partitioned to sister centromeres generated during S phase, thereby remaining stably associated through multiple cell divisions. Loading of nascent CENP-A on the megabase domains of replicated centromere DNA is shown to require passage through mitosis but not microtubule attachment. Very surprisingly, assembly and stabilization of new CENP-A-containing nucleosomes is restricted exclusively to the subsequent G1 phase, demonstrating direct coupling between progression through mitosis and assembly/maturation of the next generation of centromeres.
Jansen
Lars E T
LE
Ludwig Institute for Cancer Research and Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA.
Black
Ben E
BE
Foltz
Daniel R
DR
Cleveland
Don W
DW
D001324:Autoantigens / Q000032:analysis / Q000378:metabolism* / Q000502:physiology; D002503:Centromere / Q000378:metabolism* / Q000648:ultrastructure; D000076247:Centromere Protein A; D002843:Chromatin / Q000378:metabolism* / Q000648:ultrastructure; D002868:Chromosomal Proteins, Non-Histone / Q000032:analysis / Q000378:metabolism* / Q000502:physiology; D004261:DNA Replication; D044127:Epigenesis, Genetic; D016193:G1 Phase / Q000502:physiology; D006801:Humans; D008870:Microtubules / Q000378:metabolism / Q000648:ultrastructure; D008938:Mitosis / Q000502:physiology*; D008957:Models, Genetic; D011993:Recombinant Fusion Proteins / Q000032:analysis
D001324:Autoantigens; C000619700:CENPA protein, human; D000076247:Centromere Protein A; D002843:Chromatin; D002868:Chromosomal Proteins, Non-Histone; D011993:Recombinant Fusion Proteins