@article{KoonceTikhonenkoGraef2020,
  author    = {Koonce, Michael and Tikhonenko, Irina and Gr{\"a}f, Ralph},
  title     = {Dictyostelium cell fixation},
  series = {Methods and protocols},
  volume    = {3},
  journal   = {Methods and protocols},
  number    = {3},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2409-9279},
  doi       = {10.3390/mps3030047},
  pages     = {6},
  year      = {2020},
  abstract  = {We share two simple modifications to enhance the fixation and imaging of relatively small, motile, and rounded model cells. These include cell centrifugation and the addition of trace amounts of glutaraldehyde to existing fixation methods. Though they need to be carefully considered in each context, they have been useful to our studies of the spatial relationships of the microtubule cytoskeletal system.},
  language  = {en}
}
@article{TikhonenkoMagidsonGraefetal.2013,
  author    = {Tikhonenko, Irina and Magidson, Valentin and Gr{\"a}f, Ralph and Khodjakov, Alexey and Koonce, Michael P.},
  title     = {A kinesin-mediated mechanism that couples centrosomes to nuclei},
  series = {Cellular and molecular life sciences},
  volume    = {70},
  journal   = {Cellular and molecular life sciences},
  number    = {7},
  publisher = {Springer},
  address   = {Basel},
  issn      = {1420-682X},
  doi       = {10.1007/s00018-012-1205-0},
  pages     = {1285 -- 1296},
  year      = {2013},
  abstract  = {The M-type kinesin isoform, Kif9, has recently been implicated in maintaining a physical connection between the centrosome and nucleus in Dictyostelium discoideum. However, the mechanism by which Kif9 functions to link these two organelles remains obscure. Here we demonstrate that the Kif9 protein is localized to the nuclear envelope and is concentrated in the region underlying the centrosome point of attachment. Nuclear anchorage appears mediated through a specialized transmembrane domain located in the carboxyl terminus. Kif9 interacts with microtubules in in vitro binding assays and effects an endwise depolymerization of the polymer. These results suggest a model whereby Kif9 is anchored to the nucleus and generates a pulling force that reels the centrosome up against the nucleus. This is a novel activity for a kinesin motor, one important for progression of cells into mitosis and to ensure centrosome-nuclear parity in a multinuclear environment.},
  language  = {en}
}
@article{BatsiosGraefKoonceetal.2019,
  author    = {Batsios, Petros and Gr{\"a}f, Ralph and Koonce, Michael P. and Larochelle, Denis A. and Meyer, Irene},
  title     = {Nuclear envelope organization in Dictyostelium discoideum},
  series = {The international journal of developmental biology},
  volume    = {63},
  journal   = {The international journal of developmental biology},
  number    = {8-10},
  publisher = {UBC Pr},
  address   = {Bilbao},
  issn      = {0214-6282},
  doi       = {10.1387/ijdb.190184rg},
  pages     = {509 -- 519},
  year      = {2019},
  abstract  = {The nuclear envelope consists of the outer and the inner nuclear membrane, the nuclear lamina and the nuclear pore complexes, which regulate nuclear import and export.The major constituent of the nuclear lamina of Dictyostelium is the lamin NE81. It can form filaments like B-type lamins and it interacts with Sun 1, as well as with the LEM/HeH-family protein Src1. Sun 1 and Src1 are nuclear envelope transmembrane proteins involved in the centrosome-nucleus connection and nuclear envelope stability at the nucleolar regions, respectively. In conjunction with a KASH-domain protein, Sun 1 usually forms a so-called LINC complex.Two proteins with functions reminiscent of KASH-domain proteins at the outer nuclear membrane of Dictyostelium are known; interaptin which serves as an actin connector and the kinesin Kif9 which plays a role in the microtubule-centrosome connector. However, both of these lack the conserved KASH-domain. The link of the centrosome to the nuclear envelope is essential for the insertion of the centrosome into the nuclear envelope and the appropriate spindle formation. Moreover, centrosome insertion is involved in perm eabilization of the mitotic nucleus, which ensures access of tubulin dimers and spindle assembly factors. Our recent progress in identifying key molecular players at the nuclear envelope of Dictyostelium promises further insights into the mechanisms of nuclear envelope dynamics.},
  language  = {en}
}