小柯机器人

芬兰赫尔辛基大学Vladislav V. Verkhusha团队发现，单结构域近红外蛋白可为抗原依赖性荧光纳米抗体提供支架。相关论文于2022年5月23日在线发表在《自然—方法学》杂志上。

研究人员开发了一种17kDa的近红外（NIR）荧光蛋白（FP），称为miRFP670nano3，它在哺乳动物细胞中发出明亮的荧光，并能进行深脑成像。通过探索miRFP670nano3作为内部标签，研究人员设计了32 kDa的近红外荧光纳米抗体，称为NIR-Fbs，其稳定性和荧光强烈依赖于特定细胞内抗原的存在。NIR-Fbs能够对内源性蛋白质进行无背景的可视化，检测病毒抗原，标记表达目标分子的细胞，并通过针对两种抗原的双特异性NIR-Fbs来识别双阳性细胞群。

应用近红外-Fbs作为不稳定的融合伙伴，研究人员开发了定向降解目标蛋白、可控蛋白表达和调节酶活性的分子工具。总的来说，近红外抗体能够根据细胞内蛋白质的情况来检测和操纵各种细胞过程。

据悉，小型NIR FP非常需要作为成像应用的蛋白质标签。

附：英文原文

Title: Single-domain near-infrared protein provides a scaffold for antigen-dependent fluorescent nanobodies

Author: Oliinyk, Olena S., Baloban, Mikhail, Clark, Charles L., Carey, Erin, Pletnev, Sergei, Nimmerjahn, Axel, Verkhusha, Vladislav V.

Issue&Volume: 2022-05-23

Abstract: Small near-infrared (NIR) fluorescent proteins (FPs) are much needed as protein tags for imaging applications. We developed a 17kDa NIR FP, called miRFP670nano3, which brightly fluoresces in mammalian cells and enables deep-brain imaging. By exploring miRFP670nano3 as an internal tag, we engineered 32kDa NIR fluorescent nanobodies, termed NIR-Fbs, whose stability and fluorescence strongly depend on the presence of specific intracellular antigens. NIR-Fbs allowed background-free visualization of endogenous proteins, detection of viral antigens, labeling of cells expressing target molecules and identification of double-positive cell populations with bispecific NIR-Fbs against two antigens. Applying NIR-Fbs as destabilizing fusion partners, we developed molecular tools for directed degradation of targeted proteins, controllable protein expression and modulation of enzymatic activities. Altogether, NIR-Fbs enable the detection and manipulation of a variety of cellular processes based on the intracellular protein profile.

DOI: 10.1038/s41592-022-01467-6

Source: https://www.nature.com/articles/s41592-022-01467-6

Nature Methods：《自然—方法学》，创刊于2004年。隶属于施普林格·自然出版集团，最新IF：47.99
官方网址：https://www.nature.com/nmeth/
投稿链接：https://mts-nmeth.nature.com/cgi-bin/main.plex