Immune contribution to tentacle regeneration in adult mollusc and cnidarian models

Histological studies focusing on the early cephalic tentacle regeneration in P. canaliculata, have demonstrated that wound closure and blastema formation took place within 24 h post amputation (hpa). A Matlab® plugin allowed the semi-automated identification and quantification of a phagocytic hemocyte sub-population in the blastema. Flow cytometry analysis showed that the injection of the phagocyte-specific drug Clophosome® (45 µg/g snail) could transiently remove circulating hemocytes, that recovered the pre-treatment level within 24 h. Consistently, histological experiment demonstrated that rare hemocytes were present in the early regenerating tentacles of Clophosome®-injected snail

Identification and In Vivo Characterization of NvFP-7R, a Developmentally Regulated Red Fluorescent Protein of Nematostella vectensis

In recent years, the sea anemone Nematostella vectensis has emerged as a critical model organism for comparative genomics and developmental biology. Although Nematostella is a member of the anthozoan cnidarians (known for producing an abundance of diverse fluorescent proteins (FPs)), endogenous patterns of Nematostella fluorescence have not been described and putative FPs encoded by the genome have not been characterized.We described the spatiotemporal expression of endogenous red fluorescence during Nematostella development. Spatially, there are two patterns of red fluorescence, both restricted to the oral endoderm in developing polyps. One pattern is found in long fluorescent domains associated with the eight mesenteries and the other is found in short fluorescent domains situated between tentacles. Temporally, the long domains appear simultaneously at the 12-tentacle stage. In contrast, the short domains arise progressively between the 12- and 16-tentacle stage. To determine the source of the red fluorescence, we used bioinformatic approaches to identify all possible putative Nematostella FPs and a Drosophila S2 cell culture assay to validate NvFP-7R, a novel red fluorescent protein. We report that both the mRNA expression pattern and spectral signature of purified NvFP-7R closely match that of the endogenous red fluorescence. Strikingly, the red fluorescent pattern of NvFP-7R exhibits asymmetric expression along the directive axis, indicating that the nvfp-7r locus senses the positional information of the body plan. At the tissue level, NvFP-7R exhibits an unexpected subcellular localization and a complex complementary expression pattern in apposed epithelia sheets comprising each endodermal mesentery.These experiments not only identify NvFP-7R as a novel red fluorescent protein that could be employed as a research tool; they also uncover an unexpected spatio-temporal complexity of gene expression in an adult cnidarian. Perhaps most importantly, our results define Nematostella as a new model organism for understanding the biological function of fluorescent proteins in vivo

Prepatterning the Drosophila notum: the three genes of the iroquois complex play intrinsically distinct roles.

International audienc

Transcriptomic Analysis in the Sea Anemone Nematostella vectensis

International audienceThe sea anemone Nematostella vectensis is an emerging research model to study embryonic development and regeneration at the molecular and global transcriptomic level. Transcriptomics analysis is now routinely used to detect differential expression at the genome level. Here we present the latest procedures for isolating high-quality RNA required for next generation sequencing, as well as methods and resources for quantifying transcriptomic data

Evaluation of the bioactivities of water-soluble extracts from twelve deep-sea jellyfish species

http://www.godac.jamstec.go.jp/darwin/cruise/kaiyo/ky05-05/