UPSIDE UV effects & pigments during Sepia officinalis development

Ultraviolet (UV) radiation, especially UV-B radiation, can have detrimental effects on marine larvae and elicit behavioral changes in many adult marine organisms. Although there has been some research on marine organisms, little is known about the consequences of exposure to UV-B radiation during development in cephalopod embryo, especially our model, Sepia officinalis which lays its eggs in the intertidal area. In association with the marine biological station of ROSCOFF (Center of Biological Ressources-EMBRC)/Sorbonne University, we will test the role of the capsule in the protection of the embryo by exposing eggs with black/white or without capsule to different % of UV-B. The consequences of UV-B radiation on hatch rate, mortality and malformation will be studied. We will characterize the different pigments in capsule, determine their potential protective effects, quantify the effect of UV on expression of photosensitive receptors gene and oxidative stress gene expression, with or without capsule. 

Because of Covid pandemic, it was impossible to do the experimentation. But at the end of the lockdown, it was possible to test the viability of eggs with and without capsule, thanks to the work of Gaëtan Schires at the CRB (Roscoff). Eggs with and without capsule were incubated in adapted structures to test their viability. It was successful as embryos hatched. Radiometer measurements have been tested with a special support built using 3D printer by Sebastien Henry at the CRD (Roscoff). Capsules have been frozen for future test on pigment composition. Cédric Hubas (BOREA laboratory) will characterize them.

Funding: IDEX –SU Emergence

Partners: Centre de Ressources Biologiques-EMBRC France - Sorbonne Université, https://www.embrc-france.fr/fr, Ian Probert, Gaetan Schirès, Cécile Cabresin and collaborators

Project coordinator: Laure Bonnaud-Ponticelli, Pr. MNHN, laure.bonnaud@mnhn.fr