%0 Journal Article %J Chem Senses %D 2021 %T Exploration of chemosensory ionotropic receptors in cephalopods: the IR25 gene is expressed in the olfactory organs, suckers, and fins of Sepia officinalis. %A Aude Andouche %A Valera, Stéphane %A Sébastien Baratte %K Animals %K Cephalopoda %K Phylogeny %K Receptors, Ionotropic Glutamate %K Receptors, Odorant %K Sepia %K Smell %X

While they are mostly renowned for their visual capacities, cephalopods are also good at olfaction for prey, predator, and conspecific detection. The olfactory organs and olfactory cells are well described but olfactory receptors-genes and proteins-are still undescribed in cephalopods. We conducted a broad phylogenetic analysis of the ionotropic glutamate receptor family in mollusks (iGluR), especially to identify IR members (Ionotropic Receptors), a variant subfamily whose involvement in chemosensory functions has been shown in most studied protostomes. A total of 312 iGluRs sequences (including 111 IRs) from gastropods, bivalves, and cephalopods were identified and annotated. One orthologue of the gene coding for the chemosensory IR25 co-receptor has been found in Sepia officinalis (Soff-IR25). We searched for Soff-IR25 expression at the cellular level by in situ hybridization in whole embryos at late stages before hatching. Expression was observed in the olfactory organs, which strongly validates the chemosensory function of this receptor in cephalopods. Soff-IR25 was also detected in the developing suckers, which suggests that the unique « taste by touch » behavior that cephalopods execute with their arms and suckers share features with olfaction. Finally, Soff-IR25 positive cells were unexpectedly found in fins, the two posterior appendages of cephalopods, mostly involved in locomotory functions. This result opens new avenues of investigation to confirm fins as additional chemosensory organs in cephalopods.

%B Chem Senses %V 46 %8 2021 01 01 %G eng %R 10.1093/chemse/bjab047 %0 Journal Article %J Vie et Milieu %D 2016 %T A developmental table of embryogenesis in Sepia officinalis %A Boletzky, S.V %A Aude Andouche %A Laure Bonnaud-Ponticelli %K Cephalopoda %K Development %K Embryology %K Sepia officinalis %X

The development of several cephalopods among them Sepia officinalis (Linnaeus, 1758) has been very carefully described by Naef in the early 20th century. Here an illustrated developmental table of Sepia officinalis is proposed with a morphological description of each stage. The 30 stages are grouped into five steps of development: cleavage (stages 1 to 9), gastrulation (stages 10 to 13), organogenesis, plane phase (stages 14 to 18), organogenesis, extension phase (stages 19 to 22) and organogenesis, growth phase (stages 23 to 30), when the embryo has acquired the general adult conformation. For each stage, morphological identification criteria are proposed in order that this table is used as a lab tool for cephalopod researchers interested in development.

%B Vie et Milieu %V 66 %P 11-23 %8 May 2016 %G eng %N 1 %0 Journal Article %J Fisheries Research %D 2015 %T Species-specific PCR-RFLP for identification of early life history stages of squid and other applications to fisheries research %A McKeown, Niall J. %A Jean-Paul Robin %A Shaw, Paul W. %K Alloteuthis %K Cephalopoda %K Fisheries management %K Loligo %K Species identification %K Sustainable %B Fisheries Research %V 167 %P 207–209 %G eng %U http://www.sciencedirect.com/science/article/pii/S0165783615000442 %R 10.1016/j.fishres.2015.02.007