Natural co-habitation with soft corals influences gene expression in Bunodosoma goanense den Hartog & Vennam, 1993

This study explores the spatial associations between the sea anemone Bunodosoma goanense (Cnidaria: Actiniaria) and two soft corals, Zoanthus sp. and Palythoa sp. (Cnidaria: Zoantharia), on the rocky shores of Kunkeshwar, India, using field observations and transcriptomic analysis. Field observations revealed that B. goanense frequently exhibits a visible clearance zone when occurring within Zoanthus mats, while it coexists more closely with Palythoa. Although these spatial patterns suggest possible interaction differences, they remain correlative. We report the first transcriptomic dataset capturing gene expression variation in B. goanense across these distinct ecological contexts. Transcriptomic analysis revealed distinct gene expression profiles in the sea anemone depending on its immediate benthic neighbours. Association with Zoanthus was linked to upregulation of genes related to energy metabolism, cell proliferation, and protein synthesis, suggestive of an active physiological response. In contrast, presence within Palythoa mats was associated with a downregulation of growth-related genes and upregulation of inflammatory and stress-related pathways, indicating a distinct physiological response consistent with acclimatization. While our results do not directly test competition, they provide valuable molecular understanding of how B. goanense may adjust its physiology in response to its local biological environment in the intertidal zone.