TY - JOUR T1 - Transcriptomic stability or lability explains sensitivity to climate stressors in coralline algae JF - bioRxiv DO - 10.1101/2021.04.18.440109 SP - 2021.04.18.440109 AU - Tessa M. Page AU - Carmel McDougall AU - Ido Bar AU - Guillermo Diaz-Pulido Y1 - 2021/01/01 UR - http://biorxiv.org/content/early/2021/04/18/2021.04.18.440109.abstract N2 - Crustose coralline algae (CCA) are a group of calcifying red macroalgae crucial to tropical coral reefs because they form crusts that cement together the reef framework1. Previous research into the responses of CCA to ocean warming (OW) and ocean acidification (OA) have found reductions in calcification rates and survival2,3, with magnitude of effect being species-specific. Responses of CCA to OW and OA could be linked to evolutionary divergence time and/or their underlying molecular biology, the role of either being unknown in CCA. Here we show Sporolithon durum, a species from an earlier diverged lineage that exhibits low sensitivity to climate stressors, had little change in metabolic performance and did not significantly alter the expression of any genes when exposed to temperature and pH perturbations. In contrast, Porolithon onkodes, a species from a recently diverged lineage, reduced photosynthetic rates and had over 400 significantly differentially expressed genes in response to experimental treatments, with differential regulation of genes relating to physiological processes. We suggest earlier diverged CCA may be resistant to OW and OA conditions predicted for 2100, whereas taxa from more recently diverged lineages with demonstrated high sensitivity to climate stressors may have limited ability for acclimatisation.Competing Interest StatementThe authors have declared no competing interest. ER -