A Functionalizable Analog of the Yariv Reagent for AGP Imaging using Fluorescence Microscopy
A Functionalizable Analog of the Yariv Reagent for AGP Imaging using Fluorescence Microscopy
复制标题
使用荧光显微镜进行 AGP 成像的 Yariv 试剂的功能化类似物
DOI：
10.1021/acs.bioconjchem.3c00184
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发表时间：
2023
影响因子：
4.7
通讯作者：
Basu, Amit
中科院分区：
文献类型：
--
作者：
Rueda, Sebastian;McCubbin, Tyler J.;Shieh, Meg;Hoshing, Raghuraj;Braun, David M.;Basu, Amit
选择性结合到植物细胞壁多糖的小分子荧光探针已经有助于阐明这些聚糖的定位和功能。阿拉伯半乳聚糖蛋白（AGPs）是细胞壁蛋白聚糖，参与细胞信号传导、植物生长和程序性细胞死亡等基本功能。目前还没有能够荧光标记AGP的小分子探针。Yariv试剂是唯一一种结合AGP的小分子，已用于研究AGP功能并通过AGP-Yariv复合物沉淀分离AGP。然而，Yariv试剂不是荧光的，使得它们对于使用荧光显微镜的定位研究无效。一种荧光版本的Yariv试剂，能够结合以及成像的AGPs将提供一个强大的工具，在植物中研究AGPs。在此，我们描述了Yariv试剂的叠氮基类似物的合成，其可以进一步用荧光团官能化以提供结合AGP并且是荧光的糖缀合物。我们表明，当与βGlcYariv试剂联合使用时，改性试剂在体外结合试验中结合阿拉伯树胶。固定的玉米叶组织中的AGP的荧光成像使得能够将AGP定位于叶中的细胞壁。值得注意的是，成像也可以使用新鲜组织进行。这代表了第一个小分子探针，可用于可视化AGP使用荧光显微镜。
Small molecule fluorescent probes that bind selectively to plant cell wall polysaccharides have been instrumental in elucidating the localization and function of these glycans. Arabinogalactan proteins (AGPs) are cell wall proteoglycans implicated in essential functions such as cell signaling, plant growth, and programmed cell death. There is currently no small molecule probe capable of fluorescently labeling AGPs. The Yariv reagents are the only small molecules that bind AGPs, and have been used to study AGP function and isolate AGPs via precipitation of an AGP–Yariv complex. However, the Yariv reagents are not fluorescent, rendering them ineffective for localization studies using fluorescence microscopy. A fluorescent version of a Yariv reagent that is capable of both binding as well as imaging AGPs would provide a powerful tool for studying AGPs in planta. Herein, we describe the synthesis of an azido analog of the Yariv reagent that can be further functionalized with a fluorophore to provide a glycoconjugate that binds AGPs and is fluorescent. We show that the modified reagent binds gum arabic in in vitro binding assays when used in conjunction with the βGlcYariv reagent. Fluorescent imaging of AGPs in fixed maize leaf tissue enables localization of AGPs to cell walls in the leaf. Significantly, imaging can also be carried out using fresh tissue. This represents the first small molecule probe that can be used to visualize AGPs using fluorescence microscopy.