title: The p150 subunit of CAF-1 causes association of SUMO2/3 with the DNA replication foci.
abstract: The small ubiquitin-related modifier 2/3 (SUMO2/3) can be post-translationally conjugated to a wide variety of proteins constituting chromatin, the platform for genetic and epigenetic regulation. Nevertheless, it is unclear how SUMO2/3 and SUMO2/3-modified proteins are delivered to the chromatin fibers. Here we report that the largest subunit of chromatin assembly factor 1 (CAF-1), human p150, interacts directly and preferentially with SUMO2/3. Amino acid residue of 98-105 in p150 is essential and sufficient for SUMO2/3 interaction. p150-SUMO2/3 interaction coincided with regions that replicate chromatin fibers, because accumulation of the proliferating cell nuclear antigen (PCNA), and incorporation of bromodeoxyuridine (BrdU) were detected at foci co-localized with both p150 and SUMO2/3 during the S-phase in a cell line expressing epitope-tagged p150. Although inhibition of SUMO2/3 expression had only a small effect on p150 deposition on the replication sites, depletion of p150 led to delocalization of SUMO2/3 from the replication foci. Furthermore, p150 mutants deficient in SUMO2/3 interaction, caused a major reduction of SUMO2/3 at the replication foci. Thus, our findings suggest an expanded role of p150 as a SUMO2/3-interacting factor, and raise the intriguing possibility that p150 plays a role in promoting delivery of SUMO2/3 or SUMO2/3-modified proteins (or both) on chromatin fibers during replication.
authors.affiliation: Department of Biological Sciences, Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan.
authors.forename: Junsuke
authors.initials: J
authors.lastname: Uwada
authors.forename: Niina
authors.initials: N
authors.lastname: Tanaka
authors.forename: Yutaro
authors.initials: Y
authors.lastname: Yamaguchi
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Uchimura
authors.forename: Kei-ichi
authors.initials: K
authors.lastname: Shibahara
authors.forename: Mitsuyoshi
authors.initials: M
authors.lastname: Nakao
authors.forename: Hisato
authors.initials: H
authors.lastname: Saitoh
mesh_terms: D002843:Chromatin / Q000378:metabolism*; D056504:Chromatin Assembly Factor-1 / Q000235:genetics / Q000378:metabolism*; D004261:DNA Replication; D006367:HeLa Cells; D006801:Humans; D017434:Protein Structure, Tertiary; D016196:S Phase; D025841:Small Ubiquitin-Related Modifier Proteins / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors; D020798:Two-Hybrid System Techniques; D014452:Ubiquitins / Q000235:genetics / Q000378:metabolism*
chemical_list: C489780:CNOT8 protein, human; D002843:Chromatin; D056504:Chromatin Assembly Factor-1; C117909:SUMO2 protein, human; C492189:SUMO3 protein, human; D025841:Small Ubiquitin-Related Modifier Proteins; D014157:Transcription Factors; D014452:Ubiquitins