Combining morphology, transcriptomics, and metabolomics to analyze the core regulatory program for regulating coral growth

The coral reef ecosystem is gradually declining and on the verge of extinction. The crux of its continuous degradation lies in the fact that the growth and recovery rate of corals is far outpaced by their loss rate. Currently, our knowledge about the mechanisms governing coral growth and development remains quite limited. In this study, we developed a high-precision morphological technology approach based on photon-counting computed tomography (PCCT-CIPT). Integrated multi-omics analyses with functional experiments, uncovered a host-centered, synchronous developmental mechanism of polyp-skeleton growth that is reproducibly identified across different coral species and habitats. The Wnt-fibroblast growth factor 10 (FGF10)-MAPK/mTOR signaling axis regulates cell division and differentiation processes through c-Myc and Sox9, effectively promoting the development and maturation of coral polyp morphology. TGF-β signaling activates SMAD5, guiding cells toward differentiation into the biomineralization-associated pathways. As the polyp matures, the AMPK signaling pathway is specifically upregulated, achieving precise regulation of cell proliferation and differentiation by inhibiting the mTOR signaling pathway. During this process, the expression of genes related to biomineralization (including CA2, Lrp5, and CLMD) is gradually upregulated, enabling the transformation of coral skeletons from the construction of primary frameworks to high-density stable structures. In the early stages of coral development, steroid hormones play a key regulatory role in driving the progression of the cell cycle and the initial construction of the skeletal framework. This study preliminarily reveals a host‑controlled program regulating coral growth and development, which may offer potential targets for further exploration in coral reef restoration.