The p150N domain of chromatin assembly factor-1 regulates Ki-67 accumulation on the mitotic perichromosomal layer.
Chromatin assembly factor 1 (CAF-1) deposits histones during DNA synthesis. The p150 subunit of human CAF-1 contains an N-terminal domain (p150N) that is dispensable for histone deposition but promotes the localization of specific loci (nucleolar-associated domains [NADs]) and proteins to the nucleolus during interphase. One of the p150N-regulated proteins is proliferation antigen Ki-67, whose depletion also decreases the nucleolar association of NADs. Ki-67 is also a fundamental component of the perichromosomal layer (PCL), a sheath of proteins surrounding condensed chromosomes during mitosis. We show here that a subset of p150 localizes to the PCL during mitosis and that p150N is required for normal levels of Ki-67 accumulation on the PCL. This activity requires the sumoylation-interacting motif within p150N, which is also required for the nucleolar localization of NADs and Ki-67 during interphase. In this manner, p150N coordinates both interphase and mitotic nuclear structures via Ki67.
Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605.
Timothy D
TD
Matheson
Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605 paul.kaufman1@umassmed.edu.
Paul D
PD
Kaufman
D002453:Cell Cycle / Q000502:physiology; D002466:Cell Nucleolus / Q000378:metabolism; D002843:Chromatin / Q000378:metabolism; D056504:Chromatin Assembly Factor-1 / Q000235:genetics / Q000378:metabolism*; D022004:Chromosome Structures / Q000378:metabolism; D002875:Chromosomes / Q000378:metabolism; D006367:HeLa Cells; D006657:Histones / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007399:Interphase / Q000502:physiology; D019394:Ki-67 Antigen / Q000235:genetics / Q000378:metabolism*; D008938:Mitosis / Q000502:physiology; D014157:Transcription Factors
C489780:CNOT8 protein, human; D002843:Chromatin; D056504:Chromatin Assembly Factor-1; D006657:Histones; D019394:Ki-67 Antigen; D014157:Transcription Factors