人类肝-α-葡萄糖胺酸N-乙转移酶 (HGSNAT) 的结构
Vikas Navratna1,2, Arvind Kumar3, Jaimin K Rana1,2
1Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, 48109, United States.
bioRxiv : the preprint server for biology
|November 14, 2023
概括
肝-α-葡萄糖胺基N-乙转移酶 (HGSNAT) 功能障碍会导致粘多糖症IIIC. 我们确定了HGSNAT-乙-CoA复杂结构,揭示了对致病突变和潜在治疗点的分子洞察力.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 遗传学 遗传学 是一个
背景情况:
- 肝素硫酸盐 (HS) 降解对细胞健康至关重要,从细胞质中开始,在溶解体中完成.
- 通过肝-α-葡萄糖胺基N-乙酸转移酶 (HGSNAT) 进行HS的溶解体乙化对于其完整的分解至关重要.
- HGSNAT功能障碍导致HS积累,导致粘多糖症IIIC (MPS IIIC),一种严重的神经退行性溶酶体储存障碍,目前没有治疗方法.
研究的目的:
- 阐明MPS IIIC中HGSNAT功能和功能障碍背后的分子机制.
- 确定HGSNAT-乙-CoA复合物的高分辨率结构,代表酶反应的初始步骤.
- 将已知的MPS IIIC突变映射到确定结构上,以了解它们对HGSNAT活动的影响.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 来获得HGSNAT-乙-CoA复合物的高分辨率结构.
- 使用计算分析将已知的MPS IIIC致病突变映射到获得的结构模型上.
主要成果:
- 成功确定了HGSNAT-乙-CoA复合物的高分辨率冷EM结构.
- 该结构提供了对酶活性部位及其与乙-甲酸的相互作用的详细视图.
- 对MPS IIIC突变的映射揭示了特定的结构变化和HGSNAT功能障碍的潜在机制.
结论:
- 确定的HGSNAT-乙-CoA结构为酶的催化机制提供了前所未有的分子洞察力.
- 了解突变诱导的HGSNAT功能障碍的结构基础对于开发MPS IIIC的治疗策略至关重要.
- 这些结构信息为未来针对MPS IIIC的药物发现工作奠定了基础.
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