Vitellogenin Recognizes Cell Damage through Membrane Binding and Shields Living Cells from Reactive Oxygen Species
Vitellogenin Recognizes Cell Damage through Membrane Binding and Shields Living Cells from Reactive Oxygen Species
复制标题
DOI：
10.1074/jbc.m113.465021
复制
发表时间：
2013-09-27
影响因子：
4.8
通讯作者：
Amdam, Gro V.
中科院分区：
文献类型：
--
作者：
Havukainen, Heli;Muench, Daniel;Amdam, Gro V.
大的脂质转运蛋白参与脂质转运和多种其他分子过程。这些血清蛋白包括卵黄蛋白原，其是蛋黄前体和病原体模式识别受体，以及载脂蛋白B，其是抗炎胆固醇载体。在蜜蜂中，卵黄蛋白原作为一种抗氧化剂，卵黄蛋白原滴度升高与这种动物的寿命延长有关。在这里，我们表明，卵黄蛋白原具有细胞和膜结合活性，它优先结合死亡和受损的细胞。卵黄蛋白原直接结合磷脂酰胆碱脂质体，并以较高的亲和力结合含有磷脂酰丝氨酸的脂质体，磷脂酰丝氨酸是暴露在受损细胞中的细胞膜内小叶的脂质。卵黄蛋白原结合活细胞，而且，提高细胞的氧化应激耐受性。这项研究可以揭示为什么大的脂质转移蛋白具有一个非常保守的α-螺旋结构域，因为我们定位的卵黄蛋白原的脂质双层结合能力主要是在这个区域。我们认为，识别细胞损伤和氧化屏蔽性能是两种机制，使卵黄蛋白原延长蜜蜂寿命。
Large lipid transfer proteins are involved in lipid transportation and diverse other molecular processes. These serum proteins include vitellogenins, which are egg yolk precursors and pathogen pattern recognition receptors, and apolipoprotein B, which is an anti-inflammatory cholesterol carrier. In the honey bee, vitellogenin acts as an antioxidant, and elevated vitellogenin titer is linked to prolonged life span in this animal. Here, we show that vitellogenin has cell and membrane binding activity and that it binds preferentially to dead and damaged cells. Vitellogenin binds directly to phosphatidylcholine liposomes and with higher affinity to liposomes containing phosphatidylserine, a lipid of the inner leaflet of cell membranes that is exposed in damaged cells. Vitellogenin binding to live cells, furthermore, improves cell oxidative stress tolerance. This study can shed more light on why large lipid transfer proteins have a well conserved alpha-helical domain, because we locate the lipid bilayer-binding ability of vitellogenin largely to this region. We suggest that recognition of cell damage and oxidation shield properties are two mechanisms that allow vitellogenin to extend honey bee life span.