title: Wash interacts with lamin and affects global nuclear organization.
abstract: The cytoplasmic functions of Wiskott-Aldrich syndrome family (WAS) proteins are well established and include roles in cytoskeleton reorganization and membrane-cytoskeletal interactions important for membrane/vesicle trafficking, morphogenesis, immune response, and signal transduction. Misregulation of these proteins is associated with immune deficiency and metastasis [1-4]. Cytoplasmic WAS proteins act as effectors of Rho family GTPases and polymerize branched actin through the Arp2/3 complex [1, 5]. Previously, we identified Drosophila washout (wash) as a new member of the WAS family with essential cytoplasmic roles in early development [6, 7]. Studies in mammalian cells and Dictyostelium suggest that WASH functions primarily in a multiprotein complex that regulates endosome shape and trafficking in an Arp2/3-dependent manner [8-11]. However, roles for classically cytoplasmic proteins in the nucleus are beginning to emerge, in particular, as participants in the regulation of gene expression [12, 13]. Here, we show that Drosophila Wash is present in the nucleus, where it plays a key role in global nuclear organization. wash mutant and knockdown nuclei disrupt subnuclear structures/organelles and exhibit the abnormal wrinkled morphology reminiscent of those observed in diverse laminopathies [14-16]. We find that nuclear Wash interacts with B-type Lamin (Lamin Dm0), and, like Lamin, Wash associates with constitutive heterochromatin. Wash knockdown increases chromatin accessibility of repressive compartments and results in a global redistribution of repressive histone modifications. Thus, our results reveal a novel role for Wash in modulating nucleus morphology and in the organization of both chromatin and non-chromatin nuclear sub-structures.
authors.affiliation: Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Verboon
authors.affiliation: Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
authors.forename: Hector
authors.initials: H
authors.lastname: Rincon-Arano
authors.affiliation: Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
authors.forename: Timothy R
authors.initials: TR
authors.lastname: Werwie
authors.affiliation: Genomics Resource, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
authors.forename: Jeffrey J
authors.initials: JJ
authors.lastname: Delrow
authors.affiliation: Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
authors.forename: David
authors.initials: D
authors.lastname: Scalzo
authors.affiliation: Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
authors.forename: Vivek
authors.initials: V
authors.lastname: Nandakumar
authors.affiliation: Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Department of Radiation Oncology, University of Washington School of Medicine, Seattle, WA 98195, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Groudine
authors.affiliation: Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA. Electronic address: susanp@fredhutch.org.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Parkhurst
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D005260:Female; D055785:Gene Knockdown Techniques; D017344:Genes, Insect; D006570:Heterochromatin / Q000235:genetics / Q000378:metabolism; D034882:Lamins / Q000235:genetics / Q000378:metabolism*; D008297:Male; D009154:Mutation; D033921:Vesicular Transport Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D029721:Drosophila Proteins; D006570:Heterochromatin; C440328:Lam protein, Drosophila; D034882:Lamins; D033921:Vesicular Transport Proteins; C573645:WASH protein, Drosophila