ANGPTL8 promotes the ability of ANGPTL3 to bind and inhibit lipoprotein lipase.
ANGPTL8 promotes the ability of ANGPTL3 to bind and inhibit lipoprotein lipase.
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DOI：
10.1016/j.molmet.2017.06.014
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发表时间：
2017-10
影响因子：
8.1
通讯作者：
Davies BSJ
中科院分区：
文献类型：
--
作者：
Chi X;Britt EC;Shows HW;Hjelmaas AJ;Shetty SK;Cushing EM;Li W;Dou A;Zhang R;Davies BSJ
血管生成素样（ANGPTL）蛋白家族的几个成员，包括ANGPTL 3和ANGPTL 8，调节脂蛋白脂肪酶（LPL）活性。ANGPTL 3或ANGPTL 8的缺乏降低血浆甘油三酯水平并增加LPL活性，而任一蛋白质的过表达则相反。最近的研究表明，ANGPTL 8可能在功能上与ANGPTL 3相互作用，以改变血浆甘油三酯的清除率;然而，这种相互作用的性质仍然难以捉摸。我们测试了ANGPTL 8与ANGPTL 3形成复合物并且该复合物对于ANGPTL 3抑制血管LPL是必需的假设。我们使用免疫共沉淀、蛋白质印迹、脂肪酶活性测定和NanoBiT分裂荧光素酶系统分析了ANGPTL 3和ANGPTL 8彼此之间以及与LPL的相互作用。我们还使用腺病毒注射在缺乏ANGPTL 8的小鼠中过表达ANGPTL 3。我们发现，ANGPTL 3或ANGPTL 8单独只能在远远超过生理水平的浓度下抑制LPL，特别是当LPL与其内皮细胞受体/转运蛋白GPIHBP 1（糖基磷脂酰肌醇锚定高密度脂蛋白结合蛋白1）结合时。当蛋白质共表达时，在ANGPTL 3和ANGPTL 8之间观察到物理相互作用，并且与ANGPTL 3的共表达极大地增强了ANGPTL 8的分泌。重要的是，与单独的任一蛋白质相比，ANGPTL 3-ANGPTL 8复合物具有显著增加的抑制LPL的能力。腺病毒实验显示，ANGPTL 3的2倍过表达仅在ANGPTL 8存在下显著增加血浆甘油三酯。蛋白质相互作用分析显示ANGPTL 8极大地增加ANGPTL 3结合LPL的能力。总之，这些数据表明ANGPTL 8与ANGPTL 3结合，并且该复合物是ANGPTL 3有效结合和抑制LPL所必需的。ANGPTL 3本身不是LPL的有效抑制剂。当共表达时，ANGPTL 3和ANGPTL 8形成复合物。ANGPTL 3促进ANGPTL 8的分泌。ANGPTL 3-ANGPTL 8复合物与LPL的结合比单独的任一种蛋白质好得多。ANGPTL 3需要ANGPTL 8才能在体外和体内有效抑制LPL。
Several members of the angiopoietin-like (ANGPTL) family of proteins, including ANGPTL3 and ANGPTL8, regulate lipoprotein lipase (LPL) activity. Deficiency in either ANGPTL3 or ANGPTL8 reduces plasma triglyceride levels and increases LPL activity, whereas overexpression of either protein does the opposite. Recent studies suggest that ANGPTL8 may functionally interact with ANGPTL3 to alter clearance of plasma triglycerides; however, the nature of this interaction has remained elusive. We tested the hypothesis that ANGPTL8 forms a complex with ANGPTL3 and that this complex is necessary for the inhibition of vascular LPL by ANGPTL3. We analyzed the interactions of ANGPTL3 and ANGPTL8 with each other and with LPL using co-immunoprecipitation, western blotting, lipase activity assays, and the NanoBiT split-luciferase system. We also used adenovirus injection to overexpress ANGPTL3 in mice that lacked ANGPTL8. We found that ANGPTL3 or ANGPTL8 alone could only inhibit LPL at concentrations that far exceeded physiological levels, especially when LPL was bound to its endothelial cell receptor/transporter GPIHBP1 (glycosylphosphatidylinositol-anchored high-density lipoprotein binding protein 1). Physical interaction was observed between ANGPTL3 and ANGPTL8 when the proteins were co-expressed, and co-expression with ANGPTL3 greatly enhanced the secretion of ANGPTL8. Importantly, ANGPTL3–ANGPTL8 complexes had a dramatically increased ability to inhibit LPL compared to either protein alone. Adenovirus experiments showed that 2-fold overexpression of ANGPTL3 significantly increased plasma triglycerides only in the presence of ANGPTL8. Protein interaction assays showed that ANGPTL8 greatly increased the ability of ANGPTL3 to bind LPL. Together, these data indicate that ANGPTL8 binds to ANGPTL3 and that this complex is necessary for ANGPTL3 to efficiently bind and inhibit LPL. ANGPTL3 by itself is not a potent inhibitor of LPL. When co-expressed, ANGPTL3 and ANGPTL8 form a complex. ANGPTL3 facilitates the secretion of ANGPTL8. ANGPTL3–ANGPTL8 complexes bind to LPL much better than either protein alone. ANGPTL3 requires ANGPTL8 to efficiently inhibit LPL both in vitro and in vivo.
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影响因子：
29
作者：
Goulbourne CN;Gin P;Tatar A;Nobumori C;Hoenger A;Jiang H;Grovenor CR;Adeyo O;Esko JD;Goldberg IJ;Reue K;Tontonoz P;Bensadoun A;Beigneux AP;Young SG;Fong LG
通讯作者：
Fong LG
影响因子：
6.5
作者：
Gusarova, Viktoria;Alexa, Corey A.;Gromada, Jesper
通讯作者：
Gromada, Jesper
影响因子：
4.8
作者：
Chi, Xun;Shetty, Shwetha K.;Davies, Brandon S. J.
通讯作者：
Davies, Brandon S. J.
影响因子：
30.8
作者：
Koishi, R;Ando, Y;Furukawa, H
通讯作者：
Furukawa, H
影响因子：
4.8
作者：
Essalmani, Rachid;Susan-Resiga, Delia;Seidah, Nabil G.
通讯作者：
Seidah, Nabil G.