Differential protein abundance in the regenerating Caribbean corallimorpharian Ricordea florida

Abstract

One remarkable ability of cnidarians is their capacity to completely regenerate damaged tissue. Studies on tissue regeneration in corals in a natural setting can be challenging due to environmental variation, time and obtaining permits. Therefore, the proteomics of coral tissue regeneration in the captive corallimorpharian Ricordea florida were examined. Corallimorpharians regenerate quickly and provide copious tissue for analysis. A more detailed understanding of fragmentation and regeneration in corallimorpharians is important because sexual reproduction has not been recorded in captivity. Instead, captive population increases rely exclusively on asexual reproduction, or fragmentation, for propagation. To examine temporal protein variability during regeneration, 36 R. florida polyps were bisected across the mouth and allowed to regenerate. Regenerating whole-animal samples were collected at 6, 12 and 24 hr, as well as 2, 4 and 14 d following bisection. Tissue samples were labelled using isobaric tandem mass tags and liquid chromatography-mass spectrometry was used to quantify protein abundance as the polyps regenerated. One hundred proteins were significantly differentially abundant over the course of the 14-day experimental period. Cytochrome c, a known trigger of cell death in mammals and critical to energy metabolism in corals, was more abundant during regeneration. Identification of protein biomarkers common to regenerating corals will allow development of tools to track protein expression during stressful events. Improved understanding of regeneration can contribute to improved corallimorpharian propagation in captivity, reducing demand from the aquarium industry for wild-harvested individuals.