Adiponectin (APN), an adipose tissue-derived hormone, plays a key role in regulating energy metabolism in mammals. However, its physiological roles in teleosts remain poorly understood. In the present study, the apn gene was cloned from large yellow croaker, which was mainly expressed in the adipose, muscle and liver. Further studies showed that adaptor protein phosphotyrosine interaction PH domain and leucine zipper 1 (APPL1) was localized in the cytoplasm near the cell membrane and was directly bounded to adiponectin receptors (AdipoRs). Meanwhile, APN played a crucial role in lipid metabolism of primary muscle cells by promoting the synthesis, oxidation and transport of fatty acids, and the promoting effects were blocked by knockdown of appl1 and AdipoRs. Furthermore, the activation/inhibition of peroxisome proliferators activated receptor γ (PPARγ) enhanced/suppressed the APN-mediated lipid metabolism. Overall, results showed that APN mediated lipid metabolism through AdipoRs-APPL1 activated PPARγ and further regulated the synthesis, oxidation and transport of FA. This study will facilitate the investigation of APN functions in lipid metabolism and energy homeostasis and reveal the evolution of lipids utilization and energy homeostasis in vertebrates.

中文翻译：

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脂联素对大黄鱼（Larimichthys crocea）脂质代谢的调节。

脂联素（APN），一种来自脂肪组织的激素，在调节哺乳动物的能量代谢中起关键作用。然而，其在硬骨鱼中的生理作用仍然知之甚少。在本研究中，从大黄鱼中克隆了apn基因，其主要表达在脂肪，肌肉和肝脏中。进一步的研究表明，衔接蛋白磷酸酪氨酸相互作用的PH结构域和亮氨酸拉链1（APPL1）位于细胞膜附近的细胞质中，并直接与脂联素受体（AdipoRs）结合。同时，APN通过促进脂肪酸的合成，氧化和运输在原代肌肉细胞的脂质代谢中起关键作用，而appl1和AdipoR的敲低阻碍了其促进作用。此外，过氧化物酶体增殖物激活受体γ（PPARγ）的激活/抑制增强/抑制了APN介导的脂质代谢。总体而言，结果表明，APN通过AdipoRs-APPL1激活PPARγ介导脂质代谢，并进一步调节FA的合成，氧化和转运。这项研究将有助于调查APN在脂质代谢和能量稳态中的功能，并揭示脊椎动物脂质利用和能量稳态的演变。