Characterization of hatching glands in cephalopods
Stand-alone Project FWF No. P21135

Hatching of embryos from their eggs begins when unicellular glands release hatching enzymes. The enzymes weaken the chorionic membrane, which is then easily broken by the moving embryo. Although numerous morphological and biochemical studies exist on the hatching glands of invertebrates (such as sea urchins, insects, ascidians) and vertebrates (teleosts, amphibians, and mammals), little is known about the morphology of the hatching glands (Hoyle organ) in cephalopod hatchlings.
The glandular system is restricted to the posterior part of the dorsal mantle surface and  becomes developed in the late embryonic phase (e.g. in Sepia stage 22-23, Loligo stage 28, Octopus stage 13). The morphology of the Hoyle organ probably differs between the cephalopod species, and little is known about the composition of its secretion.
The key objectives of this proposed work are to characterize ultrastructurally the Hoyle organ of Sepia officinalis and Octopus vulgaris from development to degradation and to analyse histochemically the secretory components. The 3D-reconstruction of the glandular structures will help reach a firmer understanding of their overall complexity in both species.
The present study will contribute to our knowledge of glandular systems in cephalopods and allow comparison with hatching structures in other invertebrates and vertebrates.

Glue analysis in Salamanders
Stand-alone Project Hochschuljubiläumsfonds of the City Vienna (H-1857/2008)

Salamanders have evolved a wide variety of antipredator mechanisms. The most effective strategies are immobility, tail autotomy, color pattern, various behavior patterns and toxic, repulsive or noxious skin secretions. Apart from these tactics, salamanders also utilize adhesive secretions for defense.
To date, this adhesive antipredator strategy has only been reported, detailed investigations conerning the morphology of the glandular structures as well as the chemical nature of the glue has not been determined yet.
The central objective of this proposed work is to study the morphology of the glue glands in Hynobius dunni and to investigate the structure of the glue ultrastructurally and to analyse its composition histochemically and biochemically.

Parental analysis in Idiosepius

Numerous molecular analyses with microsatellite markers have shown that this method is a valuable tool to answer questions about genetic diversity at the population and individual level in cephalopods. Nevertheless, such studies are limited in their significance because only a small number of eggs and offspring have been investigated so far. The generally high reproductive rates of cephalopods limit complete genetic analyses of population diversity or the determination of the exact number of potential fathers for the offspring. Here, we propose Idiosepius as an ideal model for resolving this data-poor situation.
The proposed research project addresses a novel issue: analysis of paternity success among competing males will elucidate for the first time a complete picture of the advantage of the different male mating strategies (single, multiple, sneaking) in view of potential sires. It will also indicate the male’s “genetic” contribution to reproductive output, genotype plasticity and population structure in cephalopods.
The results will provide unique insights into maintenance of genetic diversity within populations and contribute to our knowledge on population dynamics in cephalopods.

Glue analysis in cephalopods
Stand-alone Project FWF No. P17193

Adhesive substances with a variety of functions are wildely known within marine animals. Some adhesive substances are used for attachment temporarily or permanently on the subsoil while other animals develop sticky traps for food gathering or secrete glue from their extremities to capture prey. Two sepiolid genera of cephalopods (Euprymna sp. and Idiosepius sp.) produce glue by means of an adhesive gland. However, the adhesive substances of these two squid taxa serve different purposes and have been explained as ecological and behavioral adaptations. Euprymna secrete glue to coat themselves totally with sand while Idiosepius use glue to stick to sea grass leaves or algae for camouflage against predators. Hiding there, they also wait for prey swimmng by. While the ultrastructure of the adhesive gland in Euprymna is well characterized, not much attention has been paid to the adhesive organ in Idiosepius. Even less is known of the function of the adhesive gland and the biochemical composition of the glue.
The main objective of this proposed work is an ultrastructural characterization of the adhesive organ and the histochemical and biochemical identification of the glue compounds Idiosepius thailandicus. The biochemical data will be useful for future industrial or medical applications. In addition the biochemical data of the glue compounds of Idiosepiidae will allow comparisons with those of the related species Euprymna.