Key Laboratory of Marine Biotechnology of Guangdong Province, Shantou University, Shantou, 515063, China; Mariculture Research Center for Subtropical Shellfish & Algae of Guangdong Province, Shantou, 515063, China; STU-UMT Joint Shellfish Research Laboratory, Shantou University, Shantou, 515063, China.
Key Laboratory of Marine Biotechnology of Guangdong Province, Shantou University, Shantou, 515063, China; Mariculture Research Center for Subtropical Shellfish & Algae of Guangdong Province, Shantou, 515063, China; STU-UMT Joint Shellfish Research Laboratory, Shantou University, Shantou, 515063, China.
Fish Shellfish Immunol. 2018 Nov;82:453-459. doi: 10.1016/j.fsi.2018.08.049. Epub 2018 Aug 24.
The noble scallop Chlamys nobilis has been a commercially important marine cultured bivalve in the Southern Sea of China for decades. Mass mortality events, however, often occur during scallops' cultivation. Mortality of up to 67%-90% was recorded at the beginning of March in 2017 in some culture areas of Nan'ao (Shantou, China), spreading to all scallops within a week. In the present study, in order to investigate the response of the noble scallop at the physiological and molecular level during mass mortality, scallops with different mortalities of 90%, 67%, and 6% were sampled from three sites at Hunter bay, Baisha bay, and Longhai, respectively. Total carotenoids content (TCC), total antioxidant capacity (TAC), malondialdehyde (MDA) content and the expression levels of three immune-related genes (toll-like receptor, C-type lectin receptor and big defensing) in different scallop tissues were determined. The scallops were divided into three groups of sub-health, lesion, and health. TAC, TCC, as well as transcript levels of CnTLR-1, Cnlec-1 and CnBD in sub-health and lesion scallops were all significantly lower (P < 0.05) than those in health scallops, while MDA in sub-health and lesion scallops were significantly higher than those in health scallops (P < 0.05). Similarly, TCC and TAC in lesion scallops were both higher than sub-health scallops. Moreover, significantly positive correlations were found between TCC and TAC (P < 0.05) and between CnTLR-1 and Cnlec-1 (P < 0.05), while significantly negative correlations were found between TCC and CnTLR-1 (P < 0.05), TCC and Cnlec-1 (P < 0.05), TAC and CnBD (P < 0.05), as well as between MDA and Cnlec-1 (P < 0.001). All the results indicate that noble scallops significantly change their physiological and molecular levels when suffering from stress, and that their antioxidant and immune response systems play important defense functions.
高贵的扇贝 Chlamys nobilis 在中国南海已被商业化养殖数十年，是一种重要的海洋养殖双壳贝类。然而，在扇贝养殖过程中，常发生大规模死亡事件。2017 年 3 月初，在中国汕头南澳的一些养殖区，死亡率高达 67%至 90%，一周内迅速蔓延至所有扇贝。本研究为探究在大规模死亡期间高贵扇贝的生理和分子水平响应，分别从 Hunter 湾、白沙湾和龙海的三个地点，采集死亡率为 90%、67%和 6%的扇贝样本。测定了不同扇贝组织中的总类胡萝卜素含量（TCC）、总抗氧化能力（TAC）、丙二醛（MDA）含量和三种免疫相关基因（toll-like receptor、C-type lectin receptor 和 big defensing）的表达水平。将扇贝分为亚健康组、病变组和健康组。结果表明，亚健康和病变组的 TAC、TCC 以及 CnTLR-1、Cnlec-1 和 CnBD 的转录水平均显著低于健康组（P<0.05），而 MDA 则显著高于健康组（P<0.05）。同样，病变组的 TCC 和 TAC 均高于亚健康组。此外，TCC 与 TAC 之间（P<0.05）以及 CnTLR-1 与 Cnlec-1 之间（P<0.05）呈显著正相关，而 TCC 与 CnTLR-1 之间（P<0.05）、TCC 与 Cnlec-1 之间（P<0.05）、TAC 与 CnBD 之间（P<0.05）以及 MDA 与 Cnlec-1 之间（P<0.001）呈显著负相关。所有结果表明，高贵扇贝在受到压力时会显著改变其生理和分子水平，其抗氧化和免疫反应系统发挥重要防御功能。
