人类LAT1-4F2hc异构氨基酸载体复合物的结构
Renhong Yan1, Xin Zhao1, Jianlin Lei2
1Beijing Advanced Innovation Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China.
Nature
|March 15, 2019
概括
研究人员阐明了L型氨基酸载体1 (LAT1) 复合体的结构,揭示了其结构和与4F2hc的相互作用. 这为LAT1提供了洞察力.
科学领域:
- 结构生物学
- 分子机制
- 生物化学
背景情况:
- L型氨基酸载体1 (LAT1),也称为SLC7A5,促进细胞膜中大型中性氨基酸,甲状腺激素和药物前体的运输.
- LAT1与4F2细胞表面抗原重链 (4F2hc; SLC3A2) 形成复合体,对其稳定性和血局部化至关重要.
- 瘤中的LAT1过度表达使其成为抗癌药物开发的重要点,但其确切的相互作用和机制尚不清楚.
研究的目的:
- 确定人类LAT1-4F2hc复合物的高分辨率结构.
- 研究LAT1和4F2hc之间的相互作用.
- 阐明LAT1-4F2hc复合物的工作机制及其在疾病中的作用.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 来解析人类LAT1-4F2hc复合物的结构.
- 对单独的复合物和在抑制剂2 - 氨基 - 2 - 诺伯纳纳碳酸的存在来确定结构.
- 进行生物化学分析以评估4F2hc的运输活性和功能作用.
主要成果:
- 冷电磁结构显示LAT1在3.3 Å和3.5 Å的分辨率内向开放的形状.
- 除了二硫酸结合之外,LAT1和4F2hc之间在细胞外,细胞内和膜外都有广泛的相互作用.
- 生物化学测定证实4F2hc对LAT1复合物的运输活动至关重要.
结论:
- 这项研究为人类LAT1-4F2hc复合体的结构提供了详细的洞察力.
- 这些发现阐明了LAT1和4F2hc之间的功能相互作用,突出了4F2hc在传送器活动中的关键作用.
- 这些特征为了解LAT1在疾病中的参与和开发向治疗提供了基础.
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