Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China.
Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China.
Environ Sci Technol. 2022 Feb 15;56(4):2497-2510. doi: 10.1021/acs.est.1c07510. Epub 2022 Feb 2.
Oyster hemocytes are the primary vehicles transporting and detoxifying metals and are regarded as important cells for the occurrence of colored oysters due to copper (Cu) contamination. However, its heterogeneous responses under Cu exposure have not been studied. Single-cell transcriptome profiling (scRNA-seq) provides high-resolution visual insights into tissue dynamics and environmental responses. Here, we used scRNA-seq to study the responses of different cell populations of hemocytes under Cu exposure in an estuarine oyster . The 1900 population-specific Cu-responsive genes were identified in 12 clusters of hemocytes, which provided a more sensitive technique for examining Cu exposure. The granulocyte, semigranulocyte, and hyalinocyte had specific responses, while the granulocyte was the most important responsive cell type and displayed heterogeneity responses of its two subtypes. In one subtype, Cu was transported with metal transporters and chelated with Cu chaperons in the cytoplasm. Excess Cu disturbed oxidative phosphorylation and induced reactive oxygen species production. However, in the other subtype, endocytosis was mainly responsible for Cu internalization, which was sequestered in membrane-bound granules. Collectively, our results provided the first mRNA expression profile of hemocytes in oysters and revealed the heterogeneity responses under Cu exposure.
牡蛎血细胞是主要的金属运输和解毒载体，由于铜 (Cu) 污染，被认为是彩色牡蛎发生的重要细胞。然而，其在 Cu 暴露下的异质反应尚未得到研究。单细胞转录组谱分析 (scRNA-seq) 为组织动态和环境反应提供了高分辨率的直观见解。在这里，我们使用 scRNA-seq 研究了河口牡蛎血细胞在 Cu 暴露下不同细胞群体的反应。在 12 个血细胞簇中鉴定出 1900 个种群特异性 Cu 反应基因，为研究 Cu 暴露提供了更敏感的技术。粒细胞、半粒细胞和透明细胞具有特异性反应，而粒细胞是最重要的反应细胞类型，显示出其两个亚型的异质反应。在一个亚型中，Cu 通过金属转运蛋白运输，并与细胞质中的 Cu 伴侣螯合。过量的 Cu 会干扰氧化磷酸化并诱导活性氧的产生。然而，在另一个亚型中，内吞作用主要负责 Cu 的内化，Cu 被隔离在膜结合的颗粒中。总之，我们的研究结果提供了牡蛎血细胞的第一个 mRNA 表达谱，并揭示了 Cu 暴露下的异质反应。
