CONICET | Buscador de Institutos y Recursos Humanos

The South American freshwater gastropod Pomacea canaliculata is a successful crop pest, responsible for great economic losses and ecological damages. Fecundity is an important component of its invasiveness. An anatomical feature that enables its remarkable reproductive effort, which is higher than that of other gastropods with similar life cycles, is the albumen gland (AG). This accessory reproductive organ synthesizes and secretes a calcareous eggshell and a perivitellin fluid that nourishes and protects the embryos. In order to shed light on the AG metabolism that enables such high reproductive effort, we evaluated the levels of its major secretion compounds relative to different reproductive efforts. The accumulation of calcium, galactogen and total proteins were quantified, as well as the gene expression and stored levels of the main proteins, PcOvo and PcPV2. We also evaluated whether copulation or oviposition could be a stimulus promoting biosynthesis. After a high reproductive effort the biochemical secretion components stored in the AG decreased and total egg dry biomass deposited almost duplicated the initial AG dry biomass. PcOvo and PcPV2 genes showed an overexpression as soon as an intermediate reproductive effort occurs. Our results show that after a high reproductive effort the AG restored all the main secretion components, but with different efficiencies according to the component. In fact, the AG was able to maintain its calcium reserves, while biosynthesis of proteins and polysaccharides was not as efficient. Therefore, biosynthesis seems to be a limiting factor for a constantly high reproductive output. So, factors affecting biosynthesis in the AG could be interesting targets for future studies considering the negative impacts of this invasive species.