MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China.
Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China.
Int J Mol Sci. 2022 Jul 18;23(14):7912. doi: 10.3390/ijms23147912.
Bivalve molluscs are filter-feeding organisms that can accumulate paralytic shellfish toxins (PST) through ingesting toxic marine dinoflagellates. While the effects of PST accumulation upon the physiology of bivalves have been documented, the underlying molecular mechanism remains poorly understood. In this study, transcriptomic analysis was performed in the gills of Zhikong scallop () after 1, 3, 5, 10, and 15 day(s) exposure of PST-producing dinoflagellate . Higher numbers of differentially expressed genes (DEGs) were detected at day 1 (1538) and day 15 (989) than that at day 3 (77), day 5 (82), and day 10 (80) after exposure, and most of the DEGs were only regulated at day 1 or day 15, highlighting different response mechanisms of scallop to PST-producing dinoflagellate at different stages of exposure. Functional enrichment results suggested that PST exposure induced the alterations of nervous system development processes and the activation of xenobiotic metabolism and substance transport processes at the acute and chronic stages of exposure, respectively, while the immune functions were inhibited by PST and might ultimately cause the activation of apoptosis. Furthermore, a weighted gene co-expression network was constructed, and ten responsive modules for toxic algae exposure were identified, among which the yellow module was found to be significantly correlated with PST content. Most of the hub genes in the yellow module were annotated as solute carriers (s) with eight being s, implying their dominant roles in regulating PST accumulation in scallop gills. Overall, our results reveal the gene set responding to and involved in PST accumulation in scallop gills, which will deepen our understanding of the molecular mechanism of bivalve resistance to PST.
双壳贝类是滤食性生物，它们通过摄食有毒海洋甲藻来积累麻痹性贝类毒素（PST）。虽然 PST 积累对贝类生理学的影响已有记录，但潜在的分子机制仍知之甚少。在这项研究中，对栉孔扇贝（）鳃组织进行了转录组分析，在 PST 产生甲藻暴露 1、3、5、10 和 15 天后。在暴露后第 1 天（1538 个）和第 15 天（989 个）检测到的差异表达基因（DEG）数量高于暴露后第 3 天（77 个）、第 5 天（82 个）和第 10 天（80 个），并且大多数 DEG 仅在第 1 天或第 15 天受到调节，突出了扇贝在暴露不同阶段对 PST 产生甲藻的不同反应机制。功能富集结果表明，PST 暴露分别在急性和慢性暴露阶段诱导神经系统发育过程的改变和外来化合物代谢和物质转运过程的激活，而免疫功能被 PST 抑制，最终可能导致细胞凋亡的激活。此外，构建了加权基因共表达网络，鉴定出 10 个对有毒藻类暴露的响应模块，其中黄色模块与 PST 含量显著相关。黄色模块中的大多数枢纽基因被注释为溶质载体（s），其中 8 个是 s，表明它们在调节扇贝鳃中 PST 积累方面的主导作用。总体而言，我们的研究结果揭示了响应 PST 积累并参与 PST 积累的基因集，这将加深我们对贝类抵抗 PST 的分子机制的理解。
