Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China.
Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian, 116023, China.
Mar Biotechnol (NY). 2024 Nov 27;27(1):11. doi: 10.1007/s10126-024-10379-9.
The Pacific oyster Crassostrea gigas is known to have an exceptional ability to accumulate zinc, which endows it with robust resistance to pathogens and makes it an excellent source of dietary zinc. ZIP1 has been identified as an important zinc uptake protein in other species, but its role in oysters remains unclear. In the present study, a ZIP1 homologue (CgZIP1-II) of the Zrt/Irt-like protein (ZIP) family was identified in C. gigas. The mRNA transcripts of CgZIP1-II were constitutively expressed in examined tissues of C. gigas, with higher levels in the hepatopancreas and gill. After zinc exposure, the mRNA transcripts of CgZIP1-II in the hepatopancreas showed a significant decline from 12 h to 14 d, while those in the gill significantly decreased at 72 h, followed by a recovery to basal level at 7 to 14 d. Immunocytochemical analysis revealed that the CgZIP1-II protein was mainly located at the plasma membrane of oyster hemocytes. Compared to the control cells, overexpression of CgZIP1-II in the transfected HEK293 cells resulted in a 2.44-fold (p < 0.05) increase in zinc content after incubation with 100 μM zinc for 24 h. Inhibition of endogenous CgZIP1-II expression with siRNAs led to a 42% reduction in zinc content in the hepatopancreas of oysters. Similarly, in vivo blocking of CgZIP1-II with anti-CgZIP1-II antibody caused a 43% decrease in zinc content in the hepatopancreas. These results collectively indicated that CgZIP1-II functioned as a zinc uptake transporter in C. gigas and played a certain role in zinc accumulation.
太平洋牡蛎（Crassostrea gigas）具有非凡的锌积累能力，这使它具有强大的病原体抗性，并成为膳食锌的良好来源。ZIP1 已被确定为其他物种中重要的锌摄取蛋白，但它在牡蛎中的作用尚不清楚。在本研究中，鉴定了太平洋牡蛎中 Zrt/Irt 样蛋白（ZIP）家族的 ZIP1 同源物（CgZIP1-II）。CgZIP1-II 的 mRNA 转录本在太平洋牡蛎的检查组织中持续表达，在肝胰腺和鳃中表达水平较高。在锌暴露后，肝胰腺中 CgZIP1-II 的 mRNA 转录本从 12 h 到 14 d 显著下降，而鳃中的 mRNA 转录本在 72 h 时显著下降，随后在 7 至 14 d 恢复到基础水平。免疫细胞化学分析表明，CgZIP1-II 蛋白主要位于牡蛎血细胞的质膜上。与对照细胞相比，在转染的 HEK293 细胞中过表达 CgZIP1-II 后，在用 100 μM 锌孵育 24 h 后，锌含量增加了 2.44 倍（p < 0.05）。用 siRNAs 抑制内源性 CgZIP1-II 表达导致牡蛎肝胰腺中的锌含量减少 42%。同样，体内用抗 CgZIP1-II 抗体阻断 CgZIP1-II 导致肝胰腺中的锌含量减少 43%。这些结果共同表明，CgZIP1-II 在 C. gigas 中作为锌摄取转运蛋白发挥作用，并在锌积累中发挥一定作用。
