Cloning of noggin gene from hydra and analysis of its functional conservation using Xenopus laevis embryos

Abstract

Hydra, a member of phylum Cnidaria that arose early in evolution, is endowed with a defined axis, organized nervous system, and active behavior. It is a powerful model system for the elucidation of evolution of developmental mechanisms in animals. Here, we describe the identification and cloning of noggin-like gene from hydra. Noggin is a secreted protein involved at multiple stages of vertebrate embryonic development including neural induction and is known to exert its effects by inhibiting the bone morphogenetic protein (BMP)-signaling pathway. Sequence analysis revealed that hydra Noggin shows considerable similarity with its orthologs at the amino acid level. When microinjected in the early Xenopus embryos, hydra noggin mRNA induced a secondary axis in 100% of the injected embryos, demonstrating functional conservation of hydra noggin in vertebrates. This was further confirmed by the partial rescue of Xenopus embryos by hydra noggin mRNA from UV-induced ventralization. By using animal cap assay in Xenopus embryos, we demonstrate that these effects of hydra noggin in Xenopus embryos are because of inhibition of BMP signaling by Noggin. Our data indicate that BMP/Noggin antagonism predates the bilaterian divergence and is conserved during the evolution.

Deep sequencing reveals unique small RNA repertoire that is regulated during head regeneration in Hydra magnipapillata

“…Hydra normally reproduces asexually by budding and sexual reproduction occurs under conditions of stress; the AEP strain can be readily induced to undergo sexual reproduction and has been used for generating transgenic lines of hydra (45). H. vulgaris Ind-Pune strain was isolated from Pune, India; it has been used for developmental studies and was recently classified as a strain of H. vulgaris (34,46). H. magnipapillata and H. vulgaris species are closely related and belong to the same monophyletic vulgaris group, although H. vulgaris AEP appears to be closer to H. carnea rather than rest of the vulgaris species (47).…”

“…All three strains of hydra, H. magnipapillata , H. vulgaris AEP and H. vulgaris Ind-Pune, were cultured in hydra medium (0.1 mM KCl, 1 mM CaCl 2 , 1 mM NaCl, 0.1 mM MgSO 4 , 1 mM Tris–Cl, pH 8.0) as described earlier at 18°C (33,34). Hydra were fed on alternate days with freshly hatched Artemia naupli but were starved 2–3 days before experiment.…”

Generic and context-dependent gene modulations duringHydrawhole body regeneration

“…S6) that was identified as a BMP inhibitor involved in the Spemann organizer in Xenopus (Spemann and Mangold, 1924;Zimmerman et al, 1996) exhibits strongly elevated expression values in both the basal and the apical regions, and virtually no expression in the central body column. The Hydra Noggin protein is able to induce a secondary axis when misexpressed in Xenopus embryos and is thus considered as homologous to the vertebrate Noggin (Chandramore et al, 2010). Similarly Chordin-like (seq37522), which also encodes an inhibitor of BMP signaling (Rentzsch et al, 2007), is expressed at higher levels at the extremities although with a lower significance for the apical region (FDR = 0.0019, Fig.…”

Karyotyping and single-gene detection using fluorescence in situ hybridization on chromosomes of Hydra magnipapillata (Cnidaria: Hydrozoa)

“…Bosch et al, 2009;Khalturin et al, 2009;Chandramore et al, 2010;Gee et al, 2010;Hartl et al, 2010;Münder et al, 2010), little information is available on their chromosomes. This is to be regretted because considerable information can be obtained by examining karyotypes: for example, sex determination depends in many cases on the presence or absence of sex chromosomes that may be morphologically differentiated.…”