CAJ | 학술논문

Hsc70与auxilin蛋白组成的系统是Hsp70／Hsp40分子伴侣系统家族的一员，在热休克反应中发挥重要作用。本文为得出auxilin蛋白J结构域的关键氨基酸，首先采用由二硫键交联的Hsc70 R171C与auxilin D876C的复合物结晶结构作为初始模型，进行分子动力学模拟，通过比较平衡后的结合部位发现，将形成二硫键的氨基酸突变为原来的氨基酸结构在结合位点上与生化结果较为相近，之后利用此结构通过拉伸动力学模拟分析了auxilin蛋白J结构域与Hsc70的ATPase功能域的解离过程，并探讨了Hsc70与auxilin蛋白之间的相互作用力。结果表明位于HPD loop上的His874，Asp876，Thr879，螺旋Ⅲ上的Glu884，Asn895，Asp896，Ser899，Glu902，Asn903为关键氨基酸，这些数据符合之前核磁共振实验证实的 T抗原 J结构域的HPD基序和螺旋Ⅲ与Hsc70的ATPase功能域之间的相互作用。
Hsc70여auxilin단백조성적계통시Hsp70／Hsp40분자반려계통가족적일원，재열휴극반응중발휘중요작용。본문위득출auxilin단백J결구역적관건안기산，수선채용유이류건교련적Hsc70 R171C여auxilin D876C적복합물결정결구작위초시모형，진행분자동역학모의，통과비교평형후적결합부위발현，장형성이류건적안기산돌변위원래적안기산결구재결합위점상여생화결과교위상근，지후이용차결구통과랍신동역학모의분석료auxilin단백J결구역여Hsc70적ATPase공능역적해리과정，병탐토료Hsc70여auxilin단백지간적상호작용력。결과표명위우HPD loop상적His874，Asp876，Thr879，라선Ⅲ상적Glu884，Asn895，Asp896，Ser899，Glu902，Asn903위관건안기산，저사수거부합지전핵자공진실험증실적 T항원 J결구역적HPD기서화라선Ⅲ여Hsc70적ATPase공능역지간적상호작용。
The Hsc70 and auxilin complex belongs to the Hsp70 and Hsp40 family, a chaperone system best known for its role in the heat shock response. The model of the Hsc70/auxilin complex molecule used in our study had the crystal structure of disulfide-bond-crosslinked complex of bovine Hsc70 R171C and bovine auxilin D876C. In order to confirm the important residues, we first analyzed the stable model after the molecular dynamics simulation ( MD) . The binding site of the mutated ( original) model was more aligned with previous biochemical results. After that, steered molecular dynamics simulations ( SMD) were applied to this stable model to investigate the dissociation of the bovine auxilin J-domain and the Hsc70 ATPase domain, and the Hsc70-auxilin interactions were also investigated. Our data indicated that His874, Asp876, and Thr879 from the HPD loop, Glu884, Asn895, Asp896, Ser899, Glu902 and Asn903 from helix Ⅲ are important residues. These data agreed with a previous NMR evidence that helix Ⅲ and HPD motif of large T antigen J-domain interacted with Hsc70 ATPase domain.