title: Trb3 regulates LR axis formation in zebrafish embryos.
abstract: Tribless family proteins are pseudokinases that lack DFG (Asp-Phe-Gly) motif in the functional kinase domain, regulating Akt and BMP pathways, insulin metabolism, hypoxia, and ubiquitination. This report concerns expression patterns and functional roles of trb3 in zebrafish embryonic development. trb3 is evolutionarily well-conserved and located on zebrafish chromosome 11. Spatiotemporal expression studies show that trb3 transcripts are abundant throughout embryogenesis, but confined to mesendodermal cells during the late blastula phase. Over-expression of trb3 ventralizes the embryos while a knockdown of trb3 using morpholino alters positioning of the heart, liver, and pancreatic buds as well as gut looping. Furthermore, constitutive activation of TGF-signaling with TARAM-A* (TGF-related type I receptor) significantly increases the level of trb3 transcripts during the late blastula phase. Over-expression of trb3 reduces the level of smurf1 transcripts, a member of TGF-signaling. We thus propose that Trb3 governs left-right (LR) axis patterning as a component of TGF-signaling in vertebrate embryonic development.
authors.affiliation: Department of Biological Sciences, College of Bioscience and Biotechnology, Chungnam National University, Daejeon, 305-764, Korea.
authors.forename: Mrudhula
authors.initials: M
authors.lastname: Anuppalle
authors.forename: Sateesh
authors.initials: S
authors.lastname: Maddirevula
authors.forename: Tae-Lin
authors.initials: TL
authors.lastname: Huh
authors.forename: Myungchull
authors.initials: M
authors.lastname: Rhee
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D036703:Blastula / Q000378:metabolism*; D019521:Body Patterning; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D047108:Embryonic Development; D018507:Gene Expression Regulation, Developmental; D055785:Gene Knockdown Techniques; D006321:Heart / Q000196:embryology; D008099:Liver / Q000196:embryology; D016415:Sequence Alignment; D015398:Signal Transduction; D016212:Transforming Growth Factor beta / Q000235:genetics / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism; D015027:Zebrafish / Q000196:embryology* / Q000378:metabolism; D029961:Zebrafish Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D018797:Cell Cycle Proteins; D016212:Transforming Growth Factor beta; D029961:Zebrafish Proteins; C000589856:trib3 protein, zebrafish; D044767:Ubiquitin-Protein Ligases