title: Identification and expression of HySmad1, a member of the R-Smad family of TGFbeta signal transducers, in the diploblastic metazoan Hydra.
abstract: Members of the Smad family of TGFbeta signal transducers are important regulators of proliferation and cell fate during axis formation, organogenesis, and tumorigenesis. A canonical TGFbeta/Smad signaling pathway is conserved in nematodes, insects, and vertebrates. However, its evolutionary origin before the divergence of protostomes and deuterostomes is unclear. Here, we present the cloning and expression of a highly conserved orthologue of receptor-activated Smads in Hydra, which represents clear evidence of the presence of TGFbeta signaling in the ancient phylum Cnidaria. HySmad1 is expressed rather uniformly during asexual reproduction and regeneration, and is transcriptionally upregulated during oocyte development. This suggests that multiple functions of TGFbeta/Smad signaling might be conserved between diploblastic and triploblastic metazoans.
authors.affiliation: Department of Molecular Cell Biology, Zoological Institute, Darmstadt University of Technology, Schnittspahnstrasse 10, 64287 Darmstadt, Germany. hobmayer@bio.tu-darmstadt.de
authors.forename: B
authors.initials: B
authors.lastname: Hobmayer
authors.forename: F
authors.initials: F
authors.lastname: Rentzsch
authors.forename: T W
authors.initials: TW
authors.lastname: Holstein
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000502:physiology; D005260:Female; D006829:Hydra / Q000235:genetics* / Q000502:physiology; D008969:Molecular Sequence Data; D009865:Oocytes / Q000502:physiology; D009866:Oogenesis / Q000502:physiology; D017434:Protein Structure, Tertiary / Q000235:genetics; D016415:Sequence Alignment; D015398:Signal Transduction / Q000235:genetics* / Q000502:physiology; D015534:Trans-Activators / Q000235:genetics* / Q000502:physiology; D016212:Transforming Growth Factor beta / Q000502:physiology*; D015854:Up-Regulation / Q000235:genetics / Q000502:physiology
chemical_list: D004268:DNA-Binding Proteins; D015534:Trans-Activators; D016212:Transforming Growth Factor beta