Loxechinus albus (Molina, 1782), commonly known as the edible red sea urchin, is an echinoderm native to the coasts of Chile and Peru. Due to the global demand for its high-quality gonads, natural populations have been subjected to significant overexploitation. This species accounts for the largest sea urchin fishery worldwide. In Chile, aquaculture initiatives aimed at larval rearing, juvenile cultivation in tanks, and subsequent fattening in natural habitats offer promising strategies both for diversifying aquaculture production and supporting the recovery of depleted coastal stocks. However, the progressive increase in ocean temperature represents a growing threat to the sustainability of aquaculture, directly affecting benthic species of commercial interest such as the red sea urchin. In this context, understanding the molecular mechanisms associated with the response to heat stress is key to evaluate their reproductive resilience and project sustainable management strategies, given the economic importance of exporting their gonads, where it is essential to characterize their transcriptomic profile under heat stress to elucidate the responses. This study aimed to analyze the transcriptomic response of L. albus gonads to heat stress conditions. Juvenile sea urchins were exposed to heat stress (16 °C, control; and 22 °C, heat stress condition) for 7 and 14 days. Total RNA was extracted from gonads for global gene expression analysis by RNA-Seq (on Illumina HiSeq X), complemented by RT-qPCR validation. These genes were associated with biological processes such as abiotic stress response and gonadal maturation, suggesting a relevant physiological impact on reproductive function. This work provides the first transcriptomic background of L. albus under heat stress and raises important implications for the aquaculture of this species under the following scenarios.
Funding: FONDECYT 1230794; FONDAP 1522A0004; FONDAP 1523A0007, FONDECYT 1251077.