Molecular characterization of the apical organ of the anthozoan Nematostella vectensis.
Bottom Line: In bilaterians they are characterised by a tuft of long cilia and receptor cells and they are associated with groups of neurons, but their relatively low morphological complexity and dispersed phylogenetic distribution have left their evolutionary relationship unresolved.To provide a foundation for a better understanding of this structure we have characterised the molecular composition of the apical organ of the sea anemone Nematostella vectensis.Our study provides a molecular characterization of the apical organ of Nematostella and represents an informative tool for future studies addressing the development, function and evolutionary history of apical organ cells.
Affiliation: Sars Centre for Marine Molecular Biology, University of Bergen, Thormøhlensgt 55, 5008 Bergen, Norway.Show MeSH
Mentions: Some of the identified apical organ genes displayed additional expression that appeared to be restricted to particular cell-types. The O-linked-mannose beta-1,2-N-acetylglucosaminyltransferase gene NvPOMGnT1-like (ao51) is expressed in scattered cells in the ectoderm and in the pharynx (Fig. 4A). NvCellulase-positive cells (ao132) are enriched in a broad domain in the aboral ectoderm and in the pharynx (Fig. 4B). Compared to the often spindle-shaped NvPOMGnT1-like expressing cells, the NvCellulase-positive cells appear more compact. On the basis of the predicted gene function and the distribution of these cells, we assume that the NvCellulase-positive cells are a particular type of gland cells (gland cells with translucent vesicles (Nakanishi et al., 2012)). One of the uncharacterized apical organ genes (ao81) is expressed in only a few ectodermal cells in the aboral half of the larvae, whereas the coiled-coil domain containing gene NvCCDC81 (ao155) can be detected in individual cells throughout the ectoderm (Fig. 4C and D).
Affiliation: Sars Centre for Marine Molecular Biology, University of Bergen, Thormøhlensgt 55, 5008 Bergen, Norway.