Stresses and defense mechanisms in reef-building corals: genetic, physiological, and ecological perspectives

Abstract

Over the past several decades, coral reef ecosystems have experienced various stresses and extensive degradation due to increased anthropogenic activity. Reef-building corals respond to stress in various ways, including bleaching. Corals exhibit defense mechanisms against stress, although many of these functions have not yet been clarified. Understanding the defense mechanisms in corals could provide important information for finding solutions to stress-related responses such as coral bleaching. The entire coral genome has recently been sequenced and this is expected to lead to breakthroughs in research on coral defense mechanisms. In this review, we describe coral bleaching, oxidative stress, antioxidants, mycosporine-like amino acids, and fluorescent proteins as responses and defense mechanisms against environmental stressors such as high temperature, strong irradiance, and ultraviolet radiation, from the perspectives of molecular biology, physiology, and ecology.