Structure of the flexible amino-terminal domain of prion protein bound to a sulfated glycan.
Structure of the flexible amino-terminal domain of prion protein bound to a sulfated glycan.
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DOI：
10.1016/j.jmb.2009.10.075
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发表时间：
2010-01-22
影响因子：
5.6
通讯作者：
Caughey B
中科院分区：
文献类型：
--
作者：
Taubner LM;Bienkiewicz EA;Copié V;Caughey B
仓鼠朊病毒蛋白（PrP）的固有无序的氨基近端结构域包含四个拷贝的高度保守的八肽序列PHGGGWGQ，其两侧是两个聚阳离子残基簇。该N-末端结构域介导硫酸化聚糖的结合，这可以深刻地影响PrP向病理形式的转化和朊病毒疾病的进展。为了研究硫酸化聚糖结合的结构后果，我们对仓鼠PrP残基23-106（PrP 23-106）及其片段与戊聚糖多硫酸酯（PPS）结合时进行了多维异质性（1H、13 C、15 N）核磁共振（NMR）、圆二色性（CD）和荧光研究。虽然大多数PrP 23-106在PPS结合时保持无序，但octrepeat区域采用了我们通过NMR确定的重复环-转角结构。CD数据证实了重复序列中的β样转角，这表明在没有PPS的情况下也存在这些转角，尽管不太明显。与PPS结合暴露了由对齐的色氨酸侧链组成的疏水表面，其间距和方向与自缔合或配体结合位点一致。独特的色氨酸基序通过固有色氨酸荧光探测，其在与PPS结合时显示PrP 23-106的增强荧光，与色氨酸侧链的比对一致。化学位移图谱确定了PPS在PrP 23-106上的结合位点，其中包括八重复组氨酸和先前与硫酸化聚糖结合相关的N-末端碱性簇。这些数据可以部分解释硫酸化聚糖如何调节PrP构象转换和寡聚化。
The intrinsically disordered amino-proximal domain of hamster prion protein (PrP) contains four copies of a highly conserved octapeptide sequence PHGGGWGQ that is flanked by two polycationic residue clusters. This N-terminal domain mediates the binding of sulfated glycans, which can profoundly influence the conversion of PrP to pathological forms and the progression of prion disease. To investigate the structural consequences of sulfated glycan binding, we performed multidimensional heteronuclear (1H, 13C, 15N) nuclear magnetic resonance (NMR), circular dichroism (CD), and fluorescence studies on hamster PrP residues 23–106 (PrP 23–106) and fragments thereof when bound to pentosan polysulfate (PPS). While the majority of PrP 23–106 remains disordered upon PPS binding, the octarepeat region adopts a repeating loop-turn structure that we have determined by NMR. The β-like turns within the repeats are corroborated by CD data, which demonstrate that these turns are also present, although less pronounced, without PPS. Binding to PPS exposes a hydrophobic surface composed of aligned tryptophan sidechains, the spacing and orientation of which are consistent with a self-association or ligand binding site. The unique tryptophan motif was probed by intrinsic tryptophan fluorescence, which displayed enhanced fluorescence of PrP 23–106 when bound to PPS, consistent with the alignment of tryptophan sidechains. Chemical shift mapping identified binding sites on PrP 23–106 for PPS, which include the octarepeat histidine and an N-terminal basic cluster previously linked to sulfated glycan binding. These data may in part explain how sulfated glycans modulate PrP conformational conversions and oligomerizations.
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影响因子：
6.8
作者：
Dunker, A. Keith;Silman, Israel;Sussman, Joel L.
通讯作者：
Sussman, Joel L.
影响因子：
4.8
作者：
Dong, Jijun;Bloom, Jesse D.;Lindquist, Susan
通讯作者：
Lindquist, Susan
影响因子：
5.4
作者：
Doh-Ura, K;Ishikawa, K;Iwaki, T
通讯作者：
Iwaki, T
影响因子：
3.4
作者：
Cordeiro, Y;Kraineva, J;Silva, JL
通讯作者：
Silva, JL
DOI：
10.1073/pnas.0809170106
发表时间：
2009-02-24
影响因子：
11.1
作者：
Antonyuk, S. V.;Trevitt, C. R.;Collinge, J.
通讯作者：
Collinge, J.