chromatin assembly factor 1 subunit B; CAF-1 subunit B; chromatin assembly factor I p60 subunit; CAF-I 60 kD subunit; CAF-Ip60; M-phase phosphoprotein 7 (CHAF1B, CAF1A, CAF1P60, MPHOSPH7, MPP7)

Function

• thought to mediate chromatin assembly in DNA replication & DNA repair
  • assembles histone octamers onto replicating DNA in vitro
  • performs 1st step of nucleosome assembly, bringing newly synthesized histones H3 & H4 to replicating DNA
  • histones H2A/H2B can bind to this chromatin precursor subsequent to DNA replication to complete the histone octamer
• component of nuclear complexes:
  • CCR4-NOT core complex
  • chromatin assembly factor 1 (CAF-1 complex)
• differentially phosphorylated during cell cycle
• during mitosis, CHAF1B is hyperphosphorylated & translocates to the cytosol
• progressively dephosphorylated from G1 to S & G2 phase
• phosphorylated CHAF1B is recruited to chromatin undergoing DNA repair after UV irradiation in G1, S or G2 phases

Structure

• belongs to the WD repeat HIR1 family
• contains 7 WD repeats

Compartment

• nucleus, DNA replication foci, cytoplasmic in M phase

Expression

• active complex is found in G1, S & G2 phases

More general terms

• protein subunit
• M-phase phosphoprotein

Component of

• CCR4-NOT core complex
• chromatin assembly factor 1 (CAF-1)

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=8208
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:8208
• OMIM: https://mirror.omim.org/entry/601245
• UniProt: http://www.uniprot.org/uniprot/Q13112.html