ATP‐binding cassette transporters protect sea urchin gametes and embryonic cells against the harmful effects of ultraviolet light

Abstract

Embryos of marine organisms whose development occurs externally are particularly sensitive to ultraviolet (UV) light (bands A and B, respectively, UVA and UVB). ATP-binding cassette (ABC) transporters are the first line of cellular defense against chemical or physical stress. The present work investigated the involvement of ABC transporters on UVA or UVB effects on eggs, spermatozoa, and embryonic cells of the sea urchin Echinometra lucunter. Gametes or embryos were exposed to UVA (3.6-14.4 kJ m(-2)) or UVB (0.112-14.4 kJ m(-2)), and embryonic development was monitored by optical microscopy at different developmental stages in the presence or absence of the ABC-transporter blockers reversin205 (ABCB1 blocker) or MK571 (ABCC1 blocker). E. lucunter eggs, spermatozoa and embryos were resistant to UVA exposure. Resistance to the harmful effects of UVB was strongly associated to ABC transporter activity (embryos > eggs > spermatozoa). ABCB1 or ABCC1 blockage promoted the injurious effects of UVA on spermatozoa. ABCC1 transporter blockage increased UVB-dependent damage in eggs while ABCB1 transporter inhibition increased harmful effects of UVB in embryonic cells. ABC-transporter activity was not, however, affected by UVB exposure. In conclusion, the present study is the first report on the protective role of ABC transporters against harmful effects of UVA and UVB on sea urchin eggs and embryonic cells.

Benzodiazepine Interference with Fertility and Embryo Development: A Preliminary Survey in the Sea Urchin Paracentrotus lividus

“…The greater and smaller effects are exerted at the intermediate and higher concentrations, respectively, and as postulated in Xenopus [6], this response suggests the activation of detoxifying pumps when DLZ reaches a "critical" concentration. The ABC transporters in sea urchins are present in different forms, in male and female gametes and embryos [58], thus providing a basis to justify the different responses observed.…”

Overview of the molecular defense systems used by sea urchin embryos to cope with UV radiation

“…Later in development, abnormal plutei have been observed for both species with apically crossed body rods (percentage of normal plutei: 5.06% ± 1.07 SD for S. granularis and 38.46% ± 21.99 for P. lividus embryos) (Nahon et al, 2008). Exposure of Echinometra lucunter eggs to UVB with doses ranging from 0.9 to 7.2 kJ/m 2 inhibited the first and second cleavage in a dose-dependent manner (Leite et al, 2014). The characteristic dose-dependent delay in cleavage has also been observed in Strongylocentrotus purpuratus embryos irradiated at 30 and 90 min post fertilization with a total dose of 41.31 kJ/m 2 UVR (290e400 nm) and delivered over a period of 60 min (Campanale et al, 2011).…”

“…Interestingly, a recent study on the Atlantic species E. lucunter using inhibitors of the ABCs transporters (ATP-Binding Cassette) showed that these multi-drug efflux transporters are involved in the protection of early embryos (2 and 4 cells), after zygotes irradiation, against the harmful effects of UVB (Leite et al, 2014). Nevertheless, how ABCs transporters operate to protect these early embryos by UVB remains to be fully elucidated.…”