Coral holobionts under different nutrient availabilities and heat stress

• Grant number: 23/14580-0
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: December 28, 2023
• End date: December 27, 2024
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: Marcelo Visentini Kitahara
• Grantee: Amana Guedes Garrido
• Supervisor: Claudia Pogoreutz
• Host Institution: Centro de Biologia Marinha (CEBIMAR). Universidade de São Paulo (USP). São Sebastião , SP, Brazil
• Institution abroad: Université de Perpignan Via Domitia, Perpignan (UPVD), France
• Associated to the scholarship: 22/10482-1 - Community structuring, phylogeography, and ecological traits from the Brazilian scleractinian endosymbiont zooxanthellae, BP.PD

Abstract

Corals are holobionts associated with dinoflagellate algae and other microorganisms in a complex multi-partner interaction. The diversity of potential associations created by the physiological and metabolic capabilities of host and symbionts, and the dynamics of symbiont community play an essential role in the environmental adaptation of corals and may guide their geographic distribution. A major driver of coral host-microbe interactions is nitrogen limitation, a mechanism for the host to regulate the proliferation of algal symbionts. Given the oligotrophic conditions in which coral reefs often thrive, nitrogen limitation implies a competition between the coral host and the algal symbionts, which can favor the structuring of alternative symbiotic communities. Corals are threatened by several local and global impacts, such as eutrophication and ocean warming, which can act synergistically jeopardizing coral reefs. Nutrient enrichment was previously associated with both increasing and decreasing coral susceptibility to bleaching, and, therefore, is a relevant factor to be better understood in terms of bleaching susceptibility. It remains unclear how corals adapted to different nutrient scenarios deals with thermal stress. To address these questions, this project aims to investigate 1) the influence of nutrient availability over coral's symbiotic composition and holobiont transcriptome, and 2) if holobionts subjected to nutrient enrichment are more susceptible to heat stress/bleaching. With this approach, we aim to better understand the main factors mediating corals' symbiotic associations, and the effect of a global impact on locally impacted corals.