Transcriptional Response of Two Core Photosystem Genes in Symbiodinium spp. Exposed to Thermal Stress

摘要: Mutualistic symbioses between scleractinian corals and endosymbiotic dinoflagellates (Symbiodinium spp.) are the foundation of coral reef ecosystems. For many coral-algal symbioses, prolonged episodes thermal stress damage symbiont's photosynthetic capability, resulting in its expulsion from host. Despite link competency symbiont expulsion, little is known about effect on expression photosystem genes Symbiodinium. This study used real-time PCR to monitor transcript abundance two important reaction center genes, psbA (encoding D1 protein II) psaA P700 I), four cultured isolates (representing ITS2-types A13, A20, B1, F2) hospite Symbiodinium spp. within Pocillopora (ITS2-types C1b-c D1). Both samples were exposed elevated temperatures (32°C) over a 7-day period examined for changes photochemistry abundance. A13 (both thermally sensitive) demonstrated significant declines both during treatment, whereas levels other types remained stable. The downregulation core could be result several different physiological mechanisms, but may ultimately limit repair rates proteins, rendering some especially susceptible stress.