Novel regulatory mechanism of condensin complexes for chromosome. Nature Structural and Molecular Biology 16 (1302-1308) Maeshima Laboratory, Biological Macromolecules Laboratory The chromosomal association of condensin II is regulated by a noncatalytic function of PP2A. Takemoto A, Maeshima K, Ikehara T, Yamaguchi K, Murayama A, Imamura S, Imamoto N, Yokoyama S, Hirano T, Watanabe Y, Hanaoka F, Yanagisawa J, Kimura K. Nature Structural & Molecular Biology 16, 1302 - 1308, 2009.　doi:10.1038/nsmb.1708 　During cell division, genomic DNA is compacted into mitotic chromosomes. Condensin complex binds to chromosomes and functions as a key player in the chromosome assembly. In vertebrates, two condensin complexes, condensin I and condensin II, make distinct contributions to this process, with different chromosomal binding. We showed that protein phosphatase 2A (PP2A), which interacts with condensin II but not condensin I, plays an essential role in targeting condensin II to chromosomes. Unexpectedly, PP2A acted as a "recruiter" protein rather than a catalytic enzyme to target condensin II to chromosomes. This recruiting activity of PP2A was inhibited by okadaic acid. Thus, our studies revealed a novel regulatory mechanism of condensin complexes for chromosome assembly. This work was done as collaboration with Dr Kimura group at University of Tsukuba. PP2A brings condensin II to the chromosome as a "recruiter". This recruiting function of PP2A is inhibited by okadaic acid. ←Back