Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy, Northwest A&F University, Yangling, Shaanxi 712100, China.
National Key Laboratory of Biochemical Engineering, National Engineering Research Center for Biotechnology (Beijing), Army Key Laboratory of Biopharmaceutical Manufacturing and Dosage Form Engineering, Institute of Process Engineering, Chinese Academy of Sciences, No. 1 North 2nd Street, Beijing 100190, China.
Int J Biol Macromol. 2018 May;111:1083-1090. doi: 10.1016/j.ijbiomac.2018.01.113. Epub 2018 Jan 31.
Chitosan oligosaccharides (COS) have the ability to improve plant resistance to pests and diseases through activating plant immune system. However, it remains unclear whether stimulating reason of COS was associated with the plasma membrane proteins. Here, the interaction of COS with wheat leaf cell demonstrated that fluorescence-labeled COS were enriched on the cell surface and the interaction of COS with plasma membrane proteins was confirmed by quartz crystal microbalance (QCM) biosensor. What's more, HPLC and SDS-PAGE analysis showed that COS binding proteins exhibited more than three peaks and the molecular weight were 66 kDa to 97 kDa, where the COS binding proteins were fished out from wheat plasma membrane proteins by the COS affinity column. More importantly, LC-MS/MS analysis demonstrated that several candidates, including W5G2U8_WHEAT (a potential wall-associated receptor kinase protein), W5HY42_WHEAT and W5I0R4_WHEAT (potential G-type lectin S-receptor-like serine/threonine-protein kinase), have the potential to be COS receptors.
壳寡糖（COS）能够通过激活植物免疫系统来提高植物的抗病虫害能力。然而，目前尚不清楚 COS 的刺激原因是否与质膜蛋白有关。在这里，通过对小麦叶片细胞的研究表明，荧光标记的 COS 被富集在细胞膜表面，并且通过石英晶体微天平（QCM）生物传感器证实了 COS 与质膜蛋白的相互作用。此外，HPLC 和 SDS-PAGE 分析表明，COS 结合蛋白表现出三个以上的峰，分子量在 66 kDa 到 97 kDa 之间，COS 结合蛋白是通过 COS 亲和柱从小麦质膜蛋白中提取出来的。更重要的是，LC-MS/MS 分析表明，包括 W5G2U8_WHEAT（一种潜在的细胞壁相关受体激酶蛋白）、W5HY42_WHEAT 和 W5I0R4_WHEAT（潜在的 G 型凝集素 S 受体样丝氨酸/苏氨酸蛋白激酶）在内的几个候选蛋白，都有可能成为 COS 的受体。
