Comparative analysis of transcriptional responses in tolerant and susceptible Pacific oysters to acute cold stress

Oysters, as sessile filter feeders in intertidal regions, experience acute and direct exposure to temperature fluctuations during emersion. While their adaptation and tolerance mechanisms to elevated temperatures are well documented, their responses to cold temperatures are less well understood.

To investigate the time-course effects of acute low temperature on the transcriptome of gill tissues, Pacific oysters (Magallana gigas) were exposed to 4 °C for 72 h. Tolerant and susceptible oysters were sampled to analyze their transcriptional changes in response to acute cold stress.

RNA-seq revealed differentially expressed transcripts in response to acute cold stress. The most pronounced differences between tolerant and susceptible oysters were observed in the cholinergic system, immune response, and antioxidant defense pathways, as well as in the modulation of various heat shock protein superfamily.

These results highlight the impact of low temperatures on oyster susceptibility and underscore the importance of transcriptional modulation in cold adaptation and resistance.