Jiangsu Key Laboratory of Brain Disease Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China.
Jiangsu Key Laboratory of Brain Disease Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou 221004, China.
Int J Biol Macromol. 2023 Aug 1;245:125456. doi: 10.1016/j.ijbiomac.2023.125456. Epub 2023 Jun 16.
Numerous articles have reported the involvement of linker in regulating bioactivity of tandem-repeat galectins. We hypothesize that linker interacts with N/C-CRDs to regulate the bioactivity of tandem-repeat galectins. To further investigate structural molecular mechanism of linker in regulating bioactivity of Gal-8, Gal-8LC was crystallized. Gal-8LC structure revealed formation of β-strand S1 by Asn174 to Pro176 from linker. S1-strand interacts with C-terminal of C-CRD via hydrogen bond interactions, mutually influencing their spatial structures. Our Gal-8 NL structure have demonstrated that linker region from Ser154 to Gln158 interacts with the N-terminal of Gal-8. Ser154 to Gln158 and Asn174 to Pro176 are likely involved in regulation of Gal-8's biological activity. Our preliminary experiment results revealed different hemagglutination and pro-apoptotic activities between full-length and truncated forms of Gal-8, indicating involvement of linker in regulating these activities. We generated several mutant and truncated forms of Gal-8 (Gal-8 M3, Gal-8 M5, Gal-8TL1, Gal-8TL2, Gal-8LC-M3 and Gal-8_177-317). Ser154 to Gln158 and Asn174 to Pro176 were found to be involved in regulating hemagglutination and pro-apoptotic activities of Gal-8. Ser154 to Gln158 and Asn174 to Pro176 are critical functional regulatory regions within linker. Our study holds significant importance in providing a profound understanding of how linker regulates biological activity of Gal-8.
许多文章报道了连接子在调节串联重复半乳糖凝集素的生物活性中的作用。我们假设连接子与 N/C-CRD 相互作用，以调节串联重复半乳糖凝集素的生物活性。为了进一步研究连接子在调节 Gal-8 生物活性中的结构分子机制，我们对 Gal-8LC 进行了结晶。Gal-8LC 的结构揭示了连接子上的 Asn174 到 Pro176 形成了β-链 S1。S1-链通过氢键相互作用与 C-CRD 的 C 端相互作用，相互影响它们的空间结构。我们的 Gal-8NL 结构表明，Ser154 到 Gln158 的连接子区域与 Gal-8 的 N 端相互作用。Ser154 到 Gln158 和 Asn174 到 Pro176 可能参与了 Gal-8 生物学活性的调节。我们的初步实验结果表明，全长和截短形式的 Gal-8 之间存在不同的血凝和促凋亡活性，表明连接子参与了这些活性的调节。我们生成了 Gal-8 的几种突变体和截短体（Gal-8M3、Gal-8M5、Gal-8TL1、Gal-8TL2、Gal-8LC-M3 和 Gal-8_177-317）。发现 Ser154 到 Gln158 和 Asn174 到 Pro176 参与调节 Gal-8 的血凝和促凋亡活性。Ser154 到 Gln158 和 Asn174 到 Pro176 是连接子中关键的功能调节区域。我们的研究对于深入了解连接子如何调节 Gal-8 的生物活性具有重要意义。
