Monika Hassel

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LiCl in concentrations exceeding 0.5 mM affects morphogenesis in Hydra vulgaris (formerly named H. attenuata) by interfering with the foot-forming system(s). Pulse treatment of Hydra bearing small buds or of animals that develop a bud within 14 h after the end of treatment prevented foot formation at the bud's base in a concentration-dependent manner. With(More)
Signalling through fibroblast growth factors (FGFR) is essential for proper morphogenesis in higher evolved triploblastic organisms. By screening for genes induced during morphogenesis in the diploblastic Hydra, we identified a receptor tyrosine kinase (kringelchen) with high similarity to FGFR tyrosine kinases. The gene is dynamically upregulated during(More)
Members of the universal stress protein (USP) family were originally identified in stressed bacteria on the basis of a shared domain, which has since been reported in a phylogenetically diverse range of prokaryotes, fungi, protists, and plants. Although not previously characterized in metazoans, here we report that USP genes are distributed in animal(More)
We have analyzed the evolution of fibroblast growth factor receptor (FGFR) tyrosine kinase genes throughout a wide range of animal phyla. No evidence for an FGFR gene was found in Porifera, but we tentatively identified an FGFR gene in the placozoan Trichoplax adhaerens. The gene encodes a protein with three immunoglobulin-like domains, a single-pass(More)
 Several studies have provided strong, but indirect evidence that signalling through pathways involving protein kinase C (PKC) plays an important role in morphogenesis and patterning in Hydra. We have cloned a gene (HvPKC2) from Hydra vulgaris which encodes a member of the nPKC subfamily. In adult polyps, HvPKC2 is expressed at high levels in two locations,(More)
Antisense RNA probes were synthesized by in vitro transcription incubating 1 μg linearized plasmid, 2 μL 100 mM dithiothreitol (DTT), 1.3 μL NTP mixture (15.4 mM each ATP, CTP, GTP, and 10 mM UTP), 0.7 μL 10 mM digoxigenin-UTP or fluorescein-UTP (Roche Applied Science, Indianapolis, IN, USA), and 0.5 μL RNAguardTM (Amersham Biosciences, Piscataway, NJ,(More)
Hydra regenerate throughout their life. We previously described early modulations in cAMP-response element-binding protein (CREB) DNA-binding activity during regeneration. We now show that the Ser-67 residue located in the P-box is a target for post-translational regulation. The antihydra CREB antiserum detected CREB-positive nuclei distributed in endoderm(More)
 A gene encoding a member of the growing family of regulatory WD-repeat proteins has been identified in Hydra vulgaris. About 80% of its deduced amino acids are identical to RACK1, which has recently been identified in rat as a receptor for activated C kinase. The presence of a consensus sequence believed to be important for interaction with protein kinase(More)
 Two different cDNA clones from Hydra (HvPKC1a and HvPKC1b) were characterized, which encode members of the cPKC family of protein kinase Cs (PKCs). The two predicted proteins differ only in their amino-terminal sequences and thus probably represent the products of alternatively spliced mRNAs from a single gene. In situ hybridization with a probe(More)
In developing embryos, boundary formation between neighbouring groups of cells is essential to establish compartments which later fulfil specialized functions. The ability to form such boundaries has likely developed early in animal evolution - due to functional requirements imposed by the necessity to separate tissues which protect the animal, take up food(More)