Liaoning Key Laboratory of Marine Animal Immunology & Disease Control, Dalian Ocean University, Dalian, 116023, China; Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian, 116023, China.
Liaoning Key Laboratory of Marine Animal Immunology & Disease Control, Dalian Ocean University, Dalian, 116023, China; Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian, 116023, China.
Fish Shellfish Immunol. 2023 Sep;140:108998. doi: 10.1016/j.fsi.2023.108998. Epub 2023 Aug 14.
AMP-activated protein kinase α subunit (AMPKα), the central regulatory molecule of energy metabolism, plays an important role in maintaining energy homeostasis and helping cells to resist the influence of various adverse factors. In the present study, an AMPKα was identified from Yesso scallop Patinopecten yessoensis (PyAMPKα). The open reading frame (ORF) of PyAMPKα was of 1599 bp encoding a putative polypeptide of 533 amino acid residues with a typical KD domain, a α-AID domain and a α-CTD domain. The deduced amino acid sequence of PyAMPKα shared 59.89-74.78% identities with AMPKαs from other species. The mRNA transcripts of PyAMPKα were found to be expressed in haemocytes and all the examined tissues, including gill, mantle, gonad, adductor muscle and hepatopancreas, with the highest expression level in adductor muscle. PyAMPKα was mainly located in cytoplasm of scallop haemocytes. At 3 h after high temperature stress treatment (25 °C), the mRNA transcripts of PyAMPKα, the phosphorylation level of PyAMPKα at Thr170 and the lactic acid (LD) content in adductor muscle all increased significantly, while the glycogen content decreased significantly. The activity of pyruvate kinase (PyPK) and the relative mRNA expression level of phosphofructokinase (PyPFK) were significantly up-regulated at 3 h after high temperature stress treatment (25 °C). Furthermore, the PyAMPKα activator AICAR could effectively upregulate the phosphorylation level of PyAMPKα, and increase activities of PyPFK and pyruvate kinase (PyPK). Meanwhile the glycogen content also declined under AICAR treatment. These results collectively suggested that PyAMPKα was involved in the high temperature stress response of scallops by enhancing glycolysis pathway of glycogen. These results would be helpful for understanding the functions of PyAMPKα in maintaining energy homeostasis under high temperature stress in scallops.
AMP 激活的蛋白激酶 α 亚基（AMPKα）是能量代谢的中央调节分子，在维持能量平衡和帮助细胞抵抗各种不利因素的影响方面发挥着重要作用。本研究从虾夷扇贝（Patinopecten yessoensis）中鉴定出一种 AMPKα（PyAMPKα）。PyAMPKα 的开放阅读框（ORF）长 1599bp，编码一个由 533 个氨基酸残基组成的假定多肽，具有典型的 KD 结构域、α-AID 结构域和 α-CTD 结构域。PyAMPKα 的推导氨基酸序列与其他物种的 AMPKα 具有 59.89-74.78%的同源性。PyAMPKα 的 mRNA 转录本在血细胞和所有检测组织中均有表达，包括鳃、套膜、性腺、闭壳肌和肝胰腺，其中在闭壳肌中的表达量最高。PyAMPKα 主要定位于扇贝血细胞的细胞质中。在高温胁迫处理（25°C） 3 小时后，PyAMPKα 的 mRNA 转录本、PyAMPKα 在 Thr170 位的磷酸化水平以及闭壳肌中的乳酸（LD）含量均显著增加，而糖原含量则显著降低。高温胁迫处理（25°C）3 小时后，丙酮酸激酶（PyPK）的活性和磷酸果糖激酶（PyPFK）的相对 mRNA 表达水平均显著上调。此外，AMPKα 激活剂 AICAR 可有效上调 PyAMPKα 的磷酸化水平，同时还能增加 PyPFK 和丙酮酸激酶（PyPK）的活性。同时，在 AICAR 处理下糖原含量也下降。这些结果共同表明，PyAMPKα 通过增强糖原的糖酵解途径参与扇贝的高温应激反应。这些结果有助于了解 PyAMPKα 在扇贝高温胁迫下维持能量平衡中的功能。
