The p150 subunit of CAF-1 causes association of SUMO2/3 with the DNA replication foci

• Published in: Biochemical and biophysical research communications Vol. 391; no. 1; pp. 407 - 413
• Main Authors: Uwada, Junsuke, Tanaka, Niina, Yamaguchi, Yutaro, Uchimura, Yasuhiro, Shibahara, Kei-ichi, Nakao, Mitsuyoshi, Saitoh, Hisato
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.01.2010
• Subjects: 60 APPLIED LIFE SCIENCES; AMINO ACIDS; ANTIGENS; BIOLOGICAL STRESS; BUILDUP; CAF-1; CHROMATIN; Chromatin - metabolism; Chromatin Assembly Factor-1 - genetics; Chromatin Assembly Factor-1 - metabolism; DNA REPLICATION; FIBERS; GENE REGULATION; HeLa Cells; Humans; INHIBITION; INTERACTIONS; MUTANTS; Post-translational modification; Protein Structure, Tertiary; PROTEINS; S Phase; Small Ubiquitin-Related Modifier Proteins - genetics; Small Ubiquitin-Related Modifier Proteins - metabolism; SUMO; Two-Hybrid System Techniques; Ubiquitins - genetics; Ubiquitins - metabolism; Post-translational modification; DNA replication; Chromatin; CAF-1; SUMO
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2009.11.071

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.