双糖的酸酶活性自我调节其受体功能
Ishita Chandel1, David Venzke1, Bailey A Wollesen1
1Department of Molecular Physiology and Biophysics and Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, University of Iowa; Iowa City, 52242, United States.
bioRxiv : the preprint server for biology
|November 24, 2025
概括
一个Golgi xylose激酶启动了母糖甘的合成. 然后,二甲糖的N终端域 (DGN) 起作用为二甲糖酸酶,去除酸盐以扩展二甲糖,揭示了二甲糖病的新型机制.
科学领域:
- 分子生物学分子生物学
- 葡萄糖生物学 葡萄糖生物学
- 细胞生物学 细胞生物学
背景情况:
- 双糖 (DG) 是一种关键的跨膜受体,参与组织发育和病原体进入.
- 马特里格利干是DG上独特的糖甘,由糖和葡萄糖酸组成,对DG的功能至关重要.
- 马特里格利干合成或长度的缺陷会导致二氧化糖病变,这是一组严重的遗传疾病.
研究的目的:
- 为了阐明调节对dystroglycan的matriglycan扩展的未知机制.
- 确定参与启动和扩展母糖甘合成的分子参与者和过程.
主要方法:
- 研究了戈尔基基酶在启动母糖甘合成中的作用.
- 描述了双糖 (DGN) 的N端域在双糖扩展中的功能.
- 利用了DGN假设的酸脱酶 (HAD) 域中的条件突变,并分析了对小鼠模型中的母糖糖长度的影响.
主要成果:
- 确定了一种戈尔基基酸酶,可以通过酸化初级基酸酶来启动母糖甘的合成.
- 双糖的N端域 (DGN),具有HAD酸酶特征的DXDXT/V基因,可以去除这种酸盐.
- 在DGN HAD类域中的条件突变导致小鼠的母糖体长度和疾病表型减少.
结论:
- 迪斯特洛甘具有其N端域 (DGN) 介导的固有甘氨酸酸酶活性.
- 这种DGN酸酶活动对于调节母糖延伸至关重要,直接影响DG功能.
- 这项发现揭示了对母糖甘合成调节的一种新机制,并提供了对双甘病变的分子基础的见解.
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