title: EB1 promotes microtubule dynamics by recruiting Sentin in Drosophila cells.
abstract: Highly conserved EB1 family proteins bind to the growing ends of microtubules, recruit multiple cargo proteins, and are critical for making dynamic microtubules in vivo. However, it is unclear how these master regulators of microtubule plus ends promote microtubule dynamics. In this paper, we identify a novel EB1 cargo protein, Sentin. Sentin depletion in Drosophila melanogaster S2 cells, similar to EB1 depletion, resulted in an increase in microtubule pausing and led to the formation of shorter spindles, without displacing EB1 from growing microtubules. We demonstrate that Sentin's association with EB1 was critical for its plus end localization and function. Furthermore, the EB1 phenotype was rescued by expressing an EBN-Sentin fusion protein in which the C-terminal cargo-binding region of EB1 is replaced with Sentin. Knockdown of Sentin attenuated plus end accumulation of Msps (mini spindles), the orthologue of XMAP215 microtubule polymerase. These results indicate that EB1 promotes dynamic microtubule behavior by recruiting the cargo protein Sentin and possibly also a microtubule polymerase to the microtubule tip.
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8601, Japan.
authors.forename: Wenjing
authors.initials: W
authors.lastname: Li
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Miki
authors.forename: Takashi
authors.initials: T
authors.lastname: Watanabe
authors.forename: Mai
authors.initials: M
authors.lastname: Kakeno
authors.forename: Ikuko
authors.initials: I
authors.lastname: Sugiyama
authors.forename: Kozo
authors.initials: K
authors.lastname: Kaibuchi
authors.forename: Gohta
authors.initials: G
authors.lastname: Goshima
mesh_terms: D000818:Animals; D002460:Cell Line; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000378:metabolism*; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism* / Q000648:ultrastructure; D034622:RNA Interference; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; C405804:EB1 microtubule binding proteins; D008869:Microtubule-Associated Proteins; D011993:Recombinant Fusion Proteins; C561110:Ssp2 protein, Drosophila