摘要
Carotenoid pigments accumulate in specific patterns in vertebrate tissues and play important roles as colorants, chromophores, and hormone precursors. However, proteins that facilitate transportation of these lipophilic pigments within cells have not been identified. We provide evidence that Aster proteins are key components for this process and show that they bind the pigments with high affinity. We observed in mice that carotenoids accumulate in tissues that express Aster-B and this accumulation can be prevented by enzymatic turnover by the BCO2 protein. Accordingly, we found opposing expression patterns of the Aster-B protein and BCO2 in the human retina that seemingly contribute to the unique carotenoid concentration in the macula lutea.
摘要译文
类胡萝卜素色素在脊椎动物组织中以特定模式积累，并作为着色剂，色彩团和激素前体起着重要作用。然而，尚未鉴定出促进这些亲脂性色素在细胞内运输的蛋白质。我们提供的证据表明，阿特蛋白是此过程的关键组成部分，并表明它们具有高亲和力的颜料。我们在小鼠中观察到，类胡萝卜素积聚在表达Aster-B的组织中，并且可以通过BCO2蛋白酶促转换来预防这种积累。因此，我们在人类视网膜中发现了Aster-B蛋白和BCO2的相反表达模式，似乎有助于黄斑lutea中独特的类胡萝卜素浓度。
Sepalika Bandara [1];Srinivasagan Ramkumar [1];Sanae Imanishi[2];Linda D. Thomas[1];Onkar B. Sawant[3];Yoshikazu Imanishi[2];Johannes von Lintig [1]. Aster proteins mediate carotenoid transport in mammalian cells[J]. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2022,119(15)