Biosynthesis in the albumen gland-capsule gland complex limits reproductive effort in the invasive apple snail Pomacea canaliculata

CADIERNO MP (ROL PROTAGÓNICO EQUIVALENTE); SAVEANU LUCÍA (ROL PROTAGÓNICO EQUIVALENTE); DREON MS; MARTÍN, P.R.; HERAS H

BIOLOGICAL BULLETIN

MARINE BIOLOGICAL LABORATORY

Año: 2018 vol. 235

0006-3185

* = rol protagónico equivalenteHigh fecundity often contributes to successful invasives. In mollusks, this may be facilitated by the albumen gland?capsule gland complex (AG-CG) that in gastropods secretes the egg perivitelline fluid that nourishes and protects embryos. AG-CG biochemistry and its relationship with fecundity remain largely unknown. We addressed these issues in Pomacea canaliculata (Lamarck, 1822), a highly invasive gastropod whose fecundity and reproductive effort exceed those of ecologically similar gastropods. We evaluated the dynamics of its major secretion compounds (calcium, polysaccharides and total proteins) as well as the gene expression and stored levels of perivitellins during key moments of the reproductive cycle, i.e. before and after first copulation and at low, medium and high reproductive output. Copulation and first oviposition do not trigger the onset of AG-CG biosynthesis. On the contrary, soon after an intermediate reproductive effort, genes encoding perivitellins overexpressed. A high reproductive effort caused a decrease in all AG-CG secretion components. Right after a high reproductive output, the AG-CG restored the main secretion components, calcium recovered baseline reserves while proteins and polysaccharides did not. These metabolic changes in AG-CG after multiple ovipositions were reflected in a reduction in egg mass but did not compromise egg quality. At the end of the cycle, egg dry weight almost doubled the initial AG-CG one. Results indicate that AG-CG biosynthesis limits a constantly high reproductive output. Therefore lowering fecundity by targeting biosynthesis could effectively reduce the rate of this species spread.