Proteomic changes associated with predator-induced morphological defences in oysters.

Area of Science:

• Ecology
• Evolutionary Biology
• Marine Biology

Background:

• Inducible defenses allow prey to alter phenotypes against predation risk.
• Local adaptation can occur when predation pressure varies spatially or temporally.
• Native Olympia oysters (Ostrea lurida) exhibit varied responses to the invasive Atlantic oyster drill (Urosalpinx cinerea).

Purpose of the Study:

• To investigate the molecular mechanisms of inducible defenses in Olympia oysters.
• To compare the inducible defense responses between oyster populations with and without prior exposure to Atlantic oyster drills.
• To understand the conserved and divergent aspects of oyster inducible defenses.

Main Methods:

• Laboratory common garden experiment with two generations of oysters.
• Exposure to cues from Atlantic oyster drills.
• Comparative proteomics to analyze protein expression differences.

Main Results:

• Both oyster populations developed thicker, harder shells with upregulated calcium transport proteins after drill exposure.
• Immune protein expression was downregulated in both populations, suggesting a trade-off with biomineralization.
• Oysters from the drill-invaded estuary exhibited smaller shell growth post-exposure, linked to isoform-specific protein expression.

Conclusions:

• Olympia oysters possess inducible defenses involving shell biomineralization and a trade-off with immune function.
• Oysters from invaded estuaries show evidence of evolved, stronger inducible defenses.
• Isoform-specific protein expression underlies population-specific variations in inducible defense strategies.