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研究発表を行った学会；
・第３２回日本分子生物学会年会
　２００９年１２月９日〜１２日（横浜）

タイトル；The p150 Subunit of CAF-1 Causes Association of SUMO2/3 With DNA Replication Foci.
　
発表者；　宇和田　淳介　氏
　　　（熊本大学　大学院自然科学研究科　斉藤寿仁研究室）

Abstract；
　Small ubiquitin-related modifier 2/3 (SUMO2/3) can be posttranslationally conjugated to a wide variety of cellular proteins, including proteins constituting chromatin, the platform for genetic and epigenetic regulation. But it is unclear how SUMO2/3 and SUMO2/3 modified proteins are delivered/deposited on chromatin fibers. p150, a largest subunit of chromatin assembly factor 1 (CAF-1) promotes chromatin assembly in the context of DNA replication. We report here that human p150 interacts directly and preferentially with SUMO2/3, for which a short polypeptide sequence 98-105 is essential and sufficient. Importantly the appearance of p150-SUMO2/3 interaction coincided with the regions replicating chromatin fibers, as accumulation of the proliferating cell nuclear antigen (PCNA) and incorporation of bromodeoxyuridine (BrdU) were detected at foci co-stained with both anti-p150 and -SUMO2/3 antibodies during S-phase in a cell line expressing epitope-tagged p150. Although inhibition of SUMO2/3 expression had little effect on p150 deposition on replication sites, depletion of p150 leaded to delocalization of SUMO2/3 from replication foci. Furthermore, p150 mutants deficient in SUMO2/3-interaction caused a major reduction of SUMO2/3 at replication foci. Thus, these findings suggest an expanded role for p150 as a SUMO2/3-interacting factor and raise an intriguing possibility that p150 plays a role in promoting delivery of SUMO2/3 and/or SUMO2/3 modified proteins on chromatin fibers during replication.