Single-cell profiling of stony coral larvae and the evolution of sensory cell types
Mikhail V. Matz
Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
Living Systems Institute, University of Exeter, Exeter, United Kingdom
Coral reefs provide food and habitats to a broad range of organisms, playing crucial roles in the biodiversity of marine ecosystems. Throughout the coral life history, a successful settlement of coral larvae onto the reefs is essential for reef recruitment and resilience of coral reefs. However, the molecular regulation of the settlement process is unclear. Here we apply single-cell RNA sequencing on the mountainous star coral Orbicella faveolata to profile larval cell types and competence dynamics. We identify nine major cell types shared across incompetent and competent larval stages, including neural, epidermal, gastrodermal, gland, and cnidocytes, reflecting all basic cell types in cnidarians. Comparative transcriptomic analysis reveals conserved cell types among coral larvae, indicating a possible single origin of these basic cell types. We find that larval neural cells express a specific set of G-protein-coupled receptors, highlighting the diversity of sensory modalities. We also discover the dynamic expressions of neurotransmitter precursors and transcription factors in distinct neural subtypes. Our study uncovers the neuronal complexity in coral larvae with settlement competency, providing the stage for comparative analysis with coral species that are more successful at recruitment.