PDF(Pubmed)
Abstract：
Marine sponges are predicted to be winners in the future ocean due to their exemplary adaptive capacity. However, while many sponge groups exhibit tolerance to a wide range of environmental insults, calcifying sponges may be more susceptible to thermo-acidic stress. To describe the gene regulatory networks that govern the stress response of the calcareous sponge, Leucetta chagosensis (class Calcarea, order Clathrinida), individuals were subjected to warming and acidification conditions based on the climate models for 2100. Transcriptome analysis and gene co-expression network reconstruction revealed that the unfolded protein response (UPR) was activated under thermo-acidic stress. Among the upregulated genes were two lineage-specific homologs of X-box binding protein 1 (XBP1), a transcription factor that activates the UPR. Alternative dimerization between these XBP1 gene products suggests a clathrinid-specific mechanism to reversibly sequester the transcription factor into an inactive form, enabling the rapid regulation of pathways linked to the UPR in clathrinid calcareous sponges. Our findings support the idea that transcription factor duplication events may refine evolutionarily conserved molecular pathways and contribute to ecological success.
摘要：
海洋海绵由于其示范性的适应能力，预计将成为未来海洋的赢家。然而,虽然许多海绵群体表现出对各种环境损害的耐受性，钙化海绵可能更容易受到热酸性应激。为了描述控制钙质海绵应激反应的基因调控网络，Leucettachagosensis（Calcarea级，orderClathrinida),根据2100年的气候模型，个体受到变暖和酸化条件的影响。转录组分析和基因共表达网络重建表明，未折叠蛋白反应（UPR）在热酸性胁迫下被激活。在上调的基因中有两个X-box结合蛋白1（XBP1）的谱系特异性同源物，激活UPR的转录因子。这些XBP1基因产物之间的选择性二聚化表明了一种锁骨特异性机制，可以将转录因子可逆地隔离为非活性形式，能够快速调节笼状钙质海绵中与UPR相关的通路。我们的发现支持转录因子复制事件可以改善进化上保守的分子途径并有助于生态成功的观点。
