title: The zebrafish dyrk1b gene is important for endoderm formation.
abstract: Nodal-signaling is required for specification of mesoderm, endoderm, establishing left-right asymmetry, and craniofacial development. Wdr68 is a WD40-repeat domain-containing protein recently shown to be required for endothelin-1 (edn1) expression and subsequent lower jaw development. Previous reports detected the Wdr68 protein in multiprotein complexes containing mammalian members of the dual-specificity tyrosine-regulated kinase (dyrk) family. Here we describe the characterization of the zebrafish dyrk1b homolog. We report the detection of a physical interaction between Dyrk1b and Wdr68. We also found perturbations of nodal signaling in dyrk1b antisense morpholino knockdown (dyrk1b-MO) animals. Specifically, we found reduced expression of lft1 and lft2 (lft1/2) during gastrulation and a near complete loss of the later asymmetric lft1/2 expression domains. Although wdr68-MO animals did not display lft1/2 expression defects during gastrulation, they displayed a near complete loss of the later asymmetric lft1/2 expression domains. While expression of ndr1 was not substantially effected during gastrulation, ndr2 expression was moderately reduced in dyrk1b-MO animals. Analysis of additional downstream components of the nodal signaling pathway in dyrk1b-MO animals revealed modestly expanded expression of the dorsal axial mesoderm marker gsc while the pan-mesodermal marker bik was largely unaffected. The endodermal markers cas and sox17 were also moderately reduced in dyrk1b-MO animals. Notably, and similar to defects previously reported for wdr68 mutant animals, we also found reduced expression of the pharyngeal pouch marker edn1 in dyrk1b-MO animals. Taken together, these data reveal a role for dyrk1b in endoderm formation and craniofacial patterning in the zebrafish.
authors.affiliation: Department of Biological Sciences, California State University Los Angeles, 5151 State University Drive, Los Angeles, CA 90032, USA.
authors.forename: Gohar
authors.initials: G
authors.lastname: Mazmanian
authors.forename: Michael
authors.initials: M
authors.lastname: Kovshilovsky
authors.forename: Debbie
authors.initials: D
authors.lastname: Yen
authors.forename: Aditya
authors.initials: A
authors.lastname: Mohanty
authors.forename: Sudipta
authors.initials: S
authors.lastname: Mohanty
authors.forename: Alex
authors.initials: A
authors.lastname: Nee
authors.forename: Robert M
authors.initials: RM
authors.lastname: Nissen
mesh_terms: D000818:Animals; D016373:DNA, Antisense / Q000235:genetics; D004625:Embryo, Nonmammalian / Q000196:embryology / Q000378:metabolism*; D004707:Endoderm / Q000196:embryology / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D055785:Gene Knockdown Techniques; D017403:In Situ Hybridization; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism; D055458:Left-Right Determination Factors / Q000235:genetics; D009687:Nuclear Proteins / Q000235:genetics; D011505:Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015027:Zebrafish / Q000196:embryology / Q000235:genetics*; D029961:Zebrafish Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D016373:DNA, Antisense; D047908:Intracellular Signaling Peptides and Proteins; D055458:Left-Right Determination Factors; D009687:Nuclear Proteins; D029961:Zebrafish Proteins; C513787:dcaf7 protein, zebrafish; C117508:lft1 protein, zebrafish; C512832:ndr2 protein, zebrafish; C549226:Dyrk1b protein, zebrafish; D011505:Protein-Tyrosine Kinases