Differential protein abundance associated with delayed regeneration of the scleractinian coral Montastraea cavernosa

Scleractinian corals provide the three-dimensional structure and function of coral reefs around the globe. These sessile animals are subject to physical injuries from a variety of sources and can completely regenerate damaged tissue as a survival mechanism; however, tissue regeneration rates vary widely within and across taxa. To explore the intraspecific differences in tissue regeneration, circular lesions (12 mm diameter × 3 mm deep) were created on 30 Montastraea cavernosa colonies at a depth of 10–12 m in the coastal waters of Carriacou, Grenada. Coral regeneration was documented at weekly intervals for 33 d. Nonlinear regression was used to generate a predictive model for lesion closure with time, and separate models were fit to corals that regenerated normally and those that had significantly delayed regeneration. A lesion created on each coral colony was re-sampled at each of 14, 21, and 31, 32, or 33 d following injury, and the polyps were flash-frozen and stored for proteomic analysis. An initial polyp sample, the 14 d, the 21 d, and the 31–33 d samples were used to quantify the difference in protein abundance as the lesions healed using tandem mass tags and liquid chromatography-mass spectrometry. One hundred thirty-one proteins were significantly differentially abundant in ‘fast’ vs. ‘slow’ M. cavernosa colonies. These proteins have been associated with inflammation, the extracellular matrix, skeleton, catabolism, and apoptosis in other corals. Differences in the abundance of proteins in these categories may have led to the observed differences between regeneration in the ‘fast’ and ‘slow’ M. cavernosa colonies.