Land snail secretomes – the identification of targets for reproductive biocontrol
Authors: Inaliguyau R T Lutschini, Kate R Ballard, Tianfang Wang, Scott F Cummins.
Invasive Mediterranean land snails have become a major cause for concern in Australia because of their affinity for grain crops and as vectors for disease. Their success is largely due to their reproductive capacity, whereby as hermaphrodites, each individual can produce thousands of offspring. Although molluscicides have been provisionally effective, snails have developed resistance mechanisms; therefore, new methods of treatment are necessary. Research at UniSC has focused on better understanding reproduction, in these snails using multi-omics system analysis, leading to the discovery of novel genes and proteins that facilitate mate finding, mating, and egg laying. My PhD research is aimed at filling gaps in the elucidation of secretome protein components in the snail (Theba pisana) that are critical for: (1) movement during mate finding (mucus trails), and (2) the egg capsules that protect developing juveniles. My proteomic investigation of mucus trails has elucidated an expanded family of acetylcholinesterase-like proteins, which are only present during the reproductive stage. These may act as conspecifics to attract and/or overcome chemicals in molluscicides (organophosphates). My investigation elucidated over 100 proteins that form T. pisana snail eggs, which can be separated into functional categories of defense, structural, and unknown functions. This discovery is the first-ever documentation made of a land snail.
This research will enhance our understanding of reproduction in pest land snails which is a critical component that drives their ability to invade globally. New knowledge will enable the production of a list of key molecular components that can be manipulated for the development of biocontrol. This research may also be used as a blueprint for the identification and development of biocontrols in other pest snail species and mollusks.