PhD Student (Adv. Janek von Byern, Gerhard Steiner)

Unit for Integrative Zoology, Department of Evolutionary Biology
University of Vienna

The freshwater gastropod Latia neritoides is an endemic species of New Zealand’s Northern Island and releases a luminescent and sticky mucus when threatened by predators. While some information has been collected on the luminescent components of this defence mucus, less is known about the adhesive mechanisms. Apart from the defence mucus the animals also release a second, non-gluing mucus type through pedal glands. This mucus, referred to as trail mucus, enhances locomotion and serves skin protection.

This project aims to perform a detailed chemical analysis of the defence mucus and characterize its underlying gland system. The mucus and its composition are investigated chemically by histochemistry, lectin affinity tests and proteomics.

In particular the proteomic data indicate that defence mucus differs from the trail mucus in terms of number and molecular size of the proteins. Determined by SDS-PAGE, different protein patterns appear for the defence and trail mucus. Based on histochemistry, minor differences between both mucus types are present, both contain sulfated and carboxylated mucosubstances and lipids. Lectin binding tests display the presence of α-linked mannose (reactive to lectin ConA), N-acetylglucosamines (lectin WGA) in both mucus types, while α-linked fucose (lectin UEA I) is only present in the trail mucus.

According to present results, defence and trail mucus are two different types of mucus, but further investigations are necessary to make a clear statement of the origin of both.

Also, the trail mucus composition appears different to that of other limnic snails, like Neritina pulligera.