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bioRxiv · 10.1101/2021.11.07.467647

OaAEP1-mediated PNA-protein conjugation enables erasable imaging of membrane protein

Abstract

Methods to efficiently and site-specifically conjugate proteins to nucleic acids could enable exciting application in bioanalytics and biotechnology. Here, we report the use of the strict protein ligase to covalently ligate a protein to a peptide nucleic acid (PNA). The rapid ligation requires only a short N-terminal GL dipeptide in target protein and a C-terminal NGL tripeptide in PNA. We demonstrate the versatility of this approach by conjugating three different types of proteins with a PNA strand. The biostable PNA strand then serves as a generic landing platform for nucleic acid hybridization. Lastly, we show the erasable imaging of EGFR on HEK293 cell membrane through toehold-mediated strand displacement. This work provides a controlled tool for precise conjugation of proteins with nucleic acids through an extremely small peptide linker and facilitates further study of membrane proteins. TOC O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=56 SRC="FIGDIR/small/467647v1_ufig1.gif" ALT="Figure 1"> View larger version (25K): org.highwire.dtl.DTLVardef@a8e3adorg.highwire.dtl.DTLVardef@1fba15borg.highwire.dtl.DTLVardef@11e606eorg.highwire.dtl.DTLVardef@14cfc49_HPS_FORMAT_FIGEXP M_FIG C_FIG

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BibTeXRIS

lu, z., li, z., Zheng, P., jia, b., liu, y., ding, x., deng, y.. 2021-11-08. OaAEP1-mediated PNA-protein conjugation enables erasable imaging of membrane protein. https://doi.org/10.1101/2021.11.07.467647

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