松材线虫Bx-sHSP16A基因克隆及蛋白质结构研究

Gene Cloning and Protein Structure Implications of a Bx-sHSP16A from Bursaphelenchus xylophilus

分子伴侣小热激蛋白(sHSPs)是线虫度过高温环境的关键因子。为开发直接针对松材线虫的防治技术提供理论依据,对松材线虫小热激蛋白Bx-sHSP16A基因进行了研究。采用SL法进行基因全长克隆,STRING9.0进行蛋白质互作网络分析,NAMD2.9进行分子动力学模拟。本研究克隆到松材线虫小热激蛋白基因Bx-sHSP16A。Bx-sHSP16A具α-crystallin保守结构域"F-polar-R-polar-aromatic-x-L-P"序列和"I/L-x-I"序列,初步判断具备分子伴侣功能。Bx-sHSP16A与多个蛋白发生互作,深入研究这些蛋白有助于了解Bx-sHSP16A在应激反应路径中的作用。Bx-sHSP16A二聚体中A亚基的"I/L-x-I"序列可以嵌入B亚基的去水合位点,契合后氢键稳定,说明Bx-sHSP16A可以形成多聚体。在应激反应过程中,去水合位点与多聚体聚合相关,Bx-sHSP16A以多聚体形式发挥分子伴侣功能。

The molecular chaperones of small heat shock proteins （sHSPs） are key components that contribute to nematode survival in higher temperatures stress response. To provide a theoretical basis for the control of Bursaphelenchus xylophilus, the small heat shock protein gene Bx-sHSP16A was studied. By the methods of nematode spliced leader the gene was cloned. The predicted interaction partners of STRING 9.0 were done to identify the protein-protein interactions. Molecular dynamics simulations were performed using NAMD 2.9. A B. xylophilus sHSP16A gene, Bx-sHSP16A, were found and well studied. The sHSP16A conserved motif ＂F-polar-R-polar-aromatic-x-L-P＂ and ＂I/L-x-I＂ were found in Bx-sHSP16A. Bx-sHSP16A had the chaperonelike functions. Bx-sHSP16A interact with many proteins, well studies of those proteins would help us understand the pathway related with sHSPs. In the Bx-sHSP16A dimer, the C terminus’＂I/L-x-I＂ of the subunit A binding with the groove of the subunit B. These results indicated that Bx-sHSP16As could form oligomer. The chaperone activity of the Bx-sHSP16As oligomer had been postulated to coincide with the exposure of hydrophobic interface sites after a temperature-regulated subunit exchange or dissociation of the oligomer.