Department of Biology, University of Vermont, 109 Carrigan Drive, Burlington, VT 05405, USA.
Proc Biol Sci. 2023 Jul 12;290(2002):20230347. doi: 10.1098/rspb.2023.0347. Epub 2023 Jul 5.
Epidemics are becoming more common and severe, however, pinpointing the causes can be challenging, particularly in marine environments. The cause of sea star wasting (SSW) disease, the ongoing, largest known panzootic of marine wildlife, is unresolved. Here, we measured gene expression longitudinally of 24 adult sea stars, collected from a recovered site, as they remained asymptomatic (8 individuals) or naturally progressed through SSW (16 individuals) in individual aquaria. Immune, tissue integrity and pro-collagen genes were more highly expressed in asymptomatic relative to wasting individuals, while hypoxia-inducible factor 1-α and RNA processing genes were more highly expressed in wasting relative to asymptomatic individuals. Integrating microbiome data from the same tissue samples, we identified genes and microbes whose abundance/growth was associated with disease status. Importantly, sea stars that remained visibly healthy showed that laboratory conditions had little effect on microbiome composition. Lastly, considering genotypes at 98 145 single-nucleotide polymorphism, we found no variants associated with final health status. These findings suggest that animals exposed to the cause(s) of SSW remain asymptomatic with an active immune response and sustained control of their collagen system while animals that succumb to wasting show evidence of responding to hypoxia and dysregulation of RNA processing systems.
然而，传染病变得越来越普遍和严重，要确定其原因具有挑战性，特别是在海洋环境中。正在发生的、已知最大规模的海洋野生动物泛发性疾病——海星消瘦症（SSW）的病因仍未确定。在这里，我们对从一个恢复的地点收集的 24 个成年海星进行了纵向基因表达测量，这些海星在个体水族馆中保持无症状（8 个个体）或自然进展为 SSW（16 个个体）。与消瘦个体相比，无症状个体的免疫、组织完整性和原胶原蛋白基因表达更高，而缺氧诱导因子 1-α 和 RNA 处理基因在消瘦个体中的表达更高。整合来自同一组织样本的微生物组数据，我们确定了与疾病状态相关的基因和微生物的丰度/生长。重要的是，那些看起来仍然健康的海星表明，实验室条件对微生物组组成几乎没有影响。最后，考虑到 98145 个单核苷酸多态性的基因型，我们没有发现与最终健康状况相关的变异。这些发现表明，暴露于 SSW 原因的动物保持无症状，具有活跃的免疫反应和对其胶原蛋白系统的持续控制，而屈服于消瘦的动物则表现出对缺氧和 RNA 处理系统失调的反应。
