基质运输的分子机制由人体过氧体 ABCD3 进行
Meghna Gupta1,2, Nitesh Kumar Khandelwal1,2, Devin J Seka1
1Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR 97239.
概括
结合ATP的磁带输送器D3 (ABCD3) 将脂肪酸输入过氧体. 低温-EM结构显示基质结合会诱导形状变化,解释其ATPase活性和运输机制.
科学领域:
- 生物化学 生化学
- 结构生物学 结构生物学
- 细胞生物学 细胞生物学
背景情况:
- 酸结合卡塞特输送器 (ABCD1-3) 将脂肪酸CoA二体输出到过氧体中.
- ABCD3 携带各种基质,突变与胆酸合成缺陷有关.
- 目前,ABCD3的基质选择性和传输机制尚不清楚.
研究的目的:
- 确定人类ABCD3.3的结构.
- 阐明基质运输和ATPase活动的机制.
主要方法:
- 低温电子显微镜 (cryo-EM) 的 ABCD3.
- 生物化学测试以评估ATPase活性.
主要成果:
- 获得的apo-ABCD3和基质结合的ABCD3 (植物醇-CoA) 的冷-EM结构.
- 基质结合会诱导ABCD3.3中的ATPase活性.
- 结构变化表明基质相互作用将核酸结合域聚集在一起.
结论:
- 结合ABCD3基质会引发形状变化和ATPase活性.
- 结构洞察力解释了基板诱导的运输机制.
- 了解ABCD3功能在过氧体进口和疾病的基础.
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