Comparative Analysis of the Soluble Proteome and the Cytolytic Activity of Unbleached and Bleached Millepora complanata ("Fire Coral") from the Mexican Caribbean

• Published in: Marine drugs 2019-07, Vol.17 (7), p.393
• Main Authors: Hernández-Elizárraga, Víctor Hugo, Olguín-López, Norma, Hernández-Matehuala, Rosalina, Ocharán-Mercado, Andrea, Cruz-Hernández, Andrés, Guevara-González, Ramón Gerardo, Caballero-Pérez, Juan, Ibarra-Alvarado, César, Sánchez-Rodríguez, Judith, Rojas-Molina, Alejandra
• Format: Article
• Language: English
• Subjects: Algae; Amino acid sequence; Animals; Anthozoa - metabolism; Astacin; Calcium; Calcium homeostasis; Caribbean Region; Cell cycle; Climate change; Colonies; Comparative analysis; Coral bleaching; Coral Reefs; Cytolytic activity; Cytoskeleton; DNA; DNA repair; Ecosystem; El Nino; El Nino phenomena; Environmental Monitoring - methods; Enzymes; Exocytosis; Fires; Gene expression; Global warming; Glycolysis; High temperature; Homeostasis; hydrozoa; Hydrozoa - metabolism; Marine invertebrates; Metabolism; Metabolites; Metalloproteinase; Millepora complanata; Nucleotide sequence; Nutrients; Organisms; Phospholipase; Phospholipase A2; Phospholipases A2 - metabolism; Pore formation; Proteins; Proteome - metabolism; Proteomes; proteomics; Proteomics - methods; Sequencing; Similarity; Southern Oscillation; Stylasteridae; Symbionts; Symbiosis; Temperature; Thermal stress; Toxins
• ISSN: 1660-3397; 1660-3397
• DOI: 10.3390/md17070393

Coral bleaching caused by global warming has resulted in massive damage to coral reefs worldwide. Studies addressing the consequences of elevated temperature have focused on organisms of the class Anthozoa, and up to now, there is little information regarding the mechanisms by which reef forming Hydrozoans face thermal stress. In this study, we carried out a comparative analysis of the soluble proteome and the cytolytic activity of unbleached and bleached ("fire coral") that inhabited reef colonies exposed to the 2015-2016 El Niño-Southern Oscillation in the Mexican Caribbean. A differential proteomic response involving proteins implicated in key cellular processes, such as glycolysis, DNA repair, stress response, calcium homeostasis, exocytosis, and cytoskeleton organization was found in bleached hydrocorals. Four of the proteins, whose levels increased in bleached specimens, displayed sequence similarity to a phospholipase A2, an astacin-like metalloprotease, and two pore forming toxins. However, a protein, which displayed sequence similarity to a calcium-independent phospholipase A2, showed lower levels in bleached cnidarians. Accordingly, the hemolytic effect of the soluble proteome of bleached hydrocorals was significantly higher, whereas the phospholipase A2 activity was significantly reduced. Our results suggest that bleached is capable of increasing its toxins production in order to balance the lack of nutrients supplied by its symbionts.