›› 2005, Vol. 48 ›› Issue (6): 854-858.

• 研究论文 • 上一篇    下一篇


汪剑霞, 胡红雨, 段家龙   

  1. 安徽农业大学生命科学学院
  • 出版日期:2005-12-29 发布日期:2005-12-20
  • 通讯作者: 段家龙

Replacement of core region of human α-Synuclein1-74 with the repeats of Bombyx mori fibrion

WANG Jian-Xia, HU Hong-Yu, DUAN Jia-Long   

  1. College of Life Sciences, Anhui Agricultural University
  • Online:2005-12-29 Published:2005-12-20


家蚕Bombyx mori丝丝心蛋白(silk fibroin)结晶域与人类帕金森综合症的致病蛋白α-突触核蛋白(α-synuclein, α-Syn)的积聚原理类似,都是由一段非常疏水的氨基酸组成的保守序列和一些无序卷曲,并在一定条件下发生整体的结构转换而发生纤维化所致。研究发现在这2种蛋白中存在的疏水片段是它们形成β折叠的关键。为了研究α-Syn蛋白的积聚核心在被别的积聚核心所替换后是否还可以正常纤维化,我们用PCR技术将家蚕丝丝心蛋白的核心片段替换α-Syn1-74(α-Syn74)的核心,组成一个重组蛋白α-Syn74SFX,纯化后温育6天,用ThT荧光和原子力显微镜检测该重组蛋白的结构,结果表明α-Syn74SFX未能发生纤维化。这说明具备能形成β片层的片段和无序卷曲这2个因素,并不能绝对使蛋白发生整体的结构转换。这对人工蚕丝的研究具有参考价值。

关键词: 家蚕, 丝心蛋白, α-突触核蛋白, 积聚, 纤维化


The formation mechanism of the crystalline domain in Bombyx mori silk fibrion is just similar to that of α-synuclein (α-Syn), which is the pathogenic protein of human Parkinson's disease. That is to say, under the certain condition, a conservative sequence made of very hydrophobic amino acids and some random coils would cause the whole structure conversion and fibrillization of a protein. It had been found that the hydrophobic region of these two proteins was the key to the formation of β sheet. In order to study whether α-synuclein can be fibrillized after its aggregating core is replaced by another, we replaced the core region of α-Syn1-74 (α-Syn74) with the core region of B. mori silk fibrion using the PCR technique, and constituted a recombinant protein named as α-Syn74SFX. After purification and incubation for 6 days, the structure of α-Syn74SFX was examined with atomic force microscope (AFM) and ThT fluorescence. The results showed that fibrillization did not occur in α-Syn74SFX. This suggests that the availability of a core region important to form β sheet and a random coil region does not necessarily make a protein to fibrillize. The research provided clues for the study of artificial silk.

Key words: Bombyx mori, fibrion, α-synuclein, aggregation, fibrillization