CORALCLIMRESPONS

Revealing the response of the coral and its endosymbiotic algae to climate changes by molecular techniques

 Partecipanti

Mappa

 Word cloud

Esplora la "nuvola delle parole (Word Cloud) per avere un'idea di massima del progetto.

 Obiettivo del progetto (Objective)

'Tropical coral reefs shelter a high rate of marine biodiversity and provide a sizeable amount of ecological services. These ecosystems of interest face tremendous and pervasive challenges from human demography sky-rockets and inherent development pressures, as well as climate change and associated sea level rise. Prospects of coral reefs conservation, critically inevitable, will achieve through the growth of understanding their ecological mechanisms. The basis for the existence of tropical coral reefs is a mutualistic relationship between the coral polyp and its endosymbiotic dinoflagellates, the Zooxanthellae (Symbiodinium spp.). Due to the consequence of global warming coral bleaching became one of the most important threats to coral reefs in the last decade. The higher temperatures and solar radiation disrupt photosynthesis in the coral’s symbiotic algae and result in the production of toxic free oxygen radicals that cause the corals to eject the algae. These stressed corals have lost their major source of energy and are effectively starving. Some corals can regain their algae and recover; but the increased stress often results in lethal coral diseases or reduced coral reproduction and growth during the next year. Surprisingly although bleaching events have been intensively studied worldwide little is known about the origin of algal rejection or the involved signalling pathways. The main objective of this innovative and original proposal is to investigate for the first time the role of the organelles of host and symbiont in coral bleaching via immunoflourescence during stress experiments. In addition, gene expression analysis will elucidate candidate genes that might be involved. This original project will lead to a better understanding of mechanism taking place during bleaching of the coral holobiont and will therefore enhance the European excellence in coral scientific community while studying this so far unknown field.'

Introduzione (Teaser)

Coral reef ecosystems are under pressure from the growing human population and its activities, as well as climate change and associated sea-level rise. A European study investigated the ecological mechanisms that support coral reef ecosystems in order to address the problem of coral bleaching.

Descrizione progetto (Article)

Tropical coral reefs are based on a mutually beneficial relationship between the coral polyp and the microorganisms it contains, the species Symbiodinium. One of the consequences of climate change is coral bleaching, which has become a major threat to corals.

Rising temperatures disrupt photosynthesis in the symbiotic algae, resulting in the production of toxic-free oxygen radicals, causing the algae to be expelled. As the stressed corals have lost their main source of energy, they starve. Although some corals regain their algae and recover, others die as a result of increased susceptibility to disease.

The EU-funded CORALCLIMRESPONS project investigated the molecular and physiological responses of coral to different environmental stresses. Researchers used different techniques such as metabolomics, transcriptomics and cytology to characterise the Symbiodinium population and the effect of coral stress.

Researchers stained and studied the organelles of the coral polyp and of Symbiodinium species using immunofluorescence microscopy. This was carried out first under normal conditions and then under conditions of thermal stress.

The team also studied the expression of genes encoding proteins involved in the production and degradation of toxic-free radicals following thermal stress. The aim was to discover candidate genes that might be involved in this process. In addition, the production of secondary metabolites by the host and its symbionts in response to the same stress were also identified.

CORALCLIMRESPONS outcomes offer a better understanding of the mechanisms behind coral reef bleaching and associated microbial communities. This will help in the discovery of key genes that can serve as biomarkers for environmental stress. The project's success will also help to maintain European excellence in the scientific study of corals.