CHAF1b, chromatin assembly factor-1 subunit b, is essential for mouse preimplantation embryos

Chromatin assembly factor-1 (CAF-1) is a three-subunit protein complex conserved throughout eukaryotes that deposits histones during DNA synthesis. Here we present a novel role for the human p150 subunit in regulating nucleolar macromolecular interactions. Acute depletion of p150 causes redistribution of multiple nucleolar proteins and reduces nucleolar association with several repetitive element–containing loci. Of note, a point mutation in a SUMO-interacting motif (SIM) within p150 abolishes nucleolar associations, whereas PCNA or HP1 interaction sites within p150 are not required for these interactions. In addition, acute depletion of SUMO-2 or the SUMO E2 ligase Ubc9 reduces α-satellite DNA association with nucleoli. The nucleolar functions of p150 are separable from its interactions with the other subunits of the CAF-1 complex because an N-terminal fragment of p150 (p150N) that cannot interact with other CAF-1 subunits is sufficient for maintaining nucleolar chromosome and protein associations. Therefore these data define novel functions for a separable domain of the p150 protein, regulating protein and DNA interactions at the nucleolus.

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Essential Role of Chromatin Assembly Factor-1–mediated Rapid Nucleosome Assembly for DNA Replication and Cell Division in Vertebrate Cells

Molecular Biology of the Cell ◽

10.1091/mbc.e06-05-0426 ◽

2007 ◽

Vol 18 (1) ◽

pp. 129-141 ◽

Cited By ~ 53

Author(s):

Yasunari Takami ◽

Tatsuya Ono ◽

Tatsuo Fukagawa ◽

Kei-ichi Shibahara ◽

Tatsuo Nakayama

Keyword(s):

Dna Replication ◽

Essential Role ◽

Chromatin Assembly ◽

Nuclear Antigen ◽

Nucleosome Assembly ◽

Chromatin Assembly Factor ◽

Assembly Factor

Chromatin assembly factor-1 (CAF-1), a complex consisting of p150, p60, and p48 subunits, is highly conserved from yeast to humans and facilitates nucleosome assembly of newly replicated DNA in vitro. To investigate roles of CAF-1 in vertebrates, we generated two conditional DT40 mutants, respectively, devoid of CAF-1p150 and p60. Depletion of each of these CAF-1 subunits led to delayed S-phase progression concomitant with slow DNA synthesis, followed by accumulation in late S/G2 phase and aberrant mitosis associated with extra centrosomes, and then the final consequence was cell death. We demonstrated that CAF-1 is necessary for rapid nucleosome formation during DNA replication in vivo as well as in vitro. Loss of CAF-1 was not associated with the apparent induction of phosphorylations of S-checkpoint kinases Chk1 and Chk2. To elucidate the precise role of domain(s) in CAF-1p150, functional dissection analyses including rescue assays were preformed. Results showed that the binding abilities of CAF-1p150 with CAF-1p60 and DNA polymerase sliding clamp proliferating cell nuclear antigen (PCNA) but not with heterochromatin protein HP1-γ are required for cell viability. These observations highlighted the essential role of CAF-1–dependent nucleosome assembly in DNA replication and cell proliferation through its interaction with PCNA.

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Chromatin Assembly Factor-1/p60 overexpression: a potential index of psoriasis severity

European Journal of Dermatology ◽

10.1684/ejd.2014.2385 ◽

2014 ◽

Vol 24 (4) ◽

pp. 509-511 ◽

Cited By ~ 1

Author(s):

Massimo Mascolo ◽

Fabio Ayala ◽

Gennaro Ilardi ◽

Anna Balato ◽

Serena Lembo

Keyword(s):

Chromatin Assembly ◽

Chromatin Assembly Factor ◽

Potential Index ◽

Assembly Factor ◽

Psoriasis Severity

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CAF (chromatin assembly factor)

Encyclopedia of Genetics, Genomics, Proteomics and Informatics ◽

10.1007/978-1-4020-6754-9_2182 ◽

2008 ◽

pp. 250-250

Keyword(s):

Chromatin Assembly ◽

Chromatin Assembly Factor ◽

Assembly Factor

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Chromatin Assembly Factor 1 (CAF-1) facilitates the establishment of facultative heterochromatin during pluripotency exit

Nucleic Acids Research ◽

10.1093/nar/gkz858 ◽

2019 ◽

Vol 47 (21) ◽

pp. 11114-11131 ◽

Cited By ~ 10

Author(s):

Liang Cheng ◽

Xu Zhang ◽

Yan Wang ◽

Haiyun Gan ◽

Xiaowei Xu ◽

...

Keyword(s):

Cell Fate ◽

Embryonic Stem ◽

Chromatin Assembly ◽

Nuclear Antigen ◽

Gene Promoters ◽

Cell Fate Determination ◽

Nucleosome Assembly ◽

Fate Determination ◽

Chromatin Assembly Factor ◽

Assembly Factor

Abstract Establishment and subsequent maintenance of distinct chromatin domains during embryonic stem cell (ESC) differentiation are crucial for lineage specification and cell fate determination. Here we show that the histone chaperone Chromatin Assembly Factor 1 (CAF-1), which is recruited to DNA replication forks through its interaction with proliferating cell nuclear antigen (PCNA) for nucleosome assembly, participates in the establishment of H3K27me3-mediated silencing during differentiation. Deletion of CAF-1 p150 subunit impairs the silencing of many genes including Oct4, Sox2 and Nanog as well as the establishment of H3K27me3 at these gene promoters during ESC differentiation. Mutations of PCNA residues involved in recruiting CAF-1 to the chromatin also result in defects in differentiation in vitro and impair early embryonic development as p150 deletion. Together, these results reveal that the CAF-1-PCNA nucleosome assembly pathway plays an important role in the establishment of H3K27me3-mediated silencing during cell fate determination.

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