Sea orphans: How embryos of marine organisms handle environmental stresses

David Epel
Hopkins Marine Station

Wednesday, March 1, 2000
3:00 p.m.—Pacific Forum

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The embryos of most marine organisms are orphans. Their parents spew sperm and eggs into the seawater, where the embryos develop with no parental protection. In this precarious environment, these embryos face environmental challenges such as exposure to ultraviolet radiation, toxins, and bacterial pathogens. Protective mechanisms must exist to thwart these challenges, but there is little information on the nature of the adaptations. Indeed, most of our information is on adult protective systems and there is little known about these first and sensitive stages of life.

This seminar will describe the cellular mechanisms that embryos use to protect themselves while in this vulnerable stage before the adult protective mechanisms have differentiated. I will consider the role of drug transporters in defending against toxins, the role of sunscreens to defend against UV radiation, and the role of symbiotic bacteria to defend against pathogens.

I will close with a discussion of recent work that suggests that in fact embryos do NOT defend themselves well, but rather destroy any damaged cells. The embryos then somehow regulate for this loss to attain normal development.

Next: Jellyfish blooms- Are populations increasing globally in response to changing ocean conditions?

 Last updated: December 19, 2000