School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore.
BMC Plant Biol. 2018 Jul 11;18(1):144. doi: 10.1186/s12870-018-1361-y.
Jasmintides jS1 and jS2 from Jasminum sambac were previously identified as a novel family of cysteine-rich peptides (CRPs) with an unusual disulfide connectivity. However, very little else is known about jasmintides, particularly their molecular diversity and functions. Here, we report the discovery and characterization of a novel suite of jasmintides from J. sambac using transcriptomic, peptidomic, structural and functional tools.
Transcriptomic analysis of leaves, flowers and roots revealed 14 unique jasmintide precursors, all of which possess a three-domain architecture comprising a signal peptide, a pro-domain and a mature jasmintide domain. Peptidomic analysis, using fractionated mixtures of jasmintides and chemical derivatization of cysteine to pseudolysine, trypsin digestion and MS/MS sequencing, revealed an additional 86 jasmintides, some of which were post-translationally modified. NMR analysis showed that jasmintide jS3 has three anti-parallel β-strands with a three-disulfide connectivity of CysI-CysV, CysII-CysIV and CysIII-CysVI, which is similar to jasmintide jS1. Jasmintide jS3 was able to withstand thermal, acidic and enzymatic degradation and, importantly, exhibited antifeedant activity against mealworm Tenebrio molitor.
Together, this study expands the existing library of jasmintides and furthers our understanding of the molecular diversity and cystine framework of CRPs as scaffolds and tools for engineering peptides targeting pests.
先前从素馨花（Jasminum sambac）中鉴定出的 Jasminetides jS1 和 jS2 是一种新型的富含半胱氨酸的肽（CRPs）家族，具有异常的二硫键连接。然而，关于 Jasminetides 的了解甚少，特别是它们的分子多样性和功能。在这里，我们使用转录组学、肽组学、结构和功能工具报告了从素馨花中发现和鉴定的一套新型 Jasminetides。
对叶片、花朵和根部的转录组分析揭示了 14 种独特的 Jasminetide 前体，它们都具有三域结构，包括信号肽、前肽和成熟 Jasminetide 域。使用 Jasminetide 的分级混合物和半胱氨酸化学衍生化为假赖氨酸、胰蛋白酶消化和 MS/MS 测序的肽组学分析，揭示了另外 86 种 Jasminetide，其中一些是经过翻译后修饰的。NMR 分析表明，Jasminetide jS3 具有三个反平行的 β-折叠，其具有三个二硫键连接 CysI-CysV、CysII-CysIV 和 CysIII-CysVI，与 Jasminetide jS1 相似。Jasminetide jS3 能够承受热、酸和酶的降解，重要的是，它对黄粉虫（Tenebrio molitor）表现出抗食活性。
总之，这项研究扩展了现有的 Jasminetide 文库，并进一步了解了作为工程肽的支架和工具的 CRP 的分子多样性和胱氨酸框架，以针对害虫。
