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Department of Pharmacology

 
Author(s): 
Liu, DS, Phipps, WS, Loh, KH, Howarth, M, Ting, AY
Abstract: 

We present a methodology for targeting quantum dots to specific proteins on living cells in two steps. In the first step, Escherichia coli lipoic acid ligase (LplA) site-specifically attaches 10-bromodecanoic acid onto a 13 amino acid recognition sequence that is genetically fused to a protein of interest. In the second step, quantum dots derivatized with HaloTag, a modified haloalkane dehalogenase, react with the ligated bromodecanoic acid to form a covalent adduct. We found this targeting method to be specific, fast, and fully orthogonal to a previously reported and analogous quantum dot targeting method using E. coli biotin ligase and streptavidin. We used these two methods in combination for two-color quantum dot visualization of different proteins expressed on the same cell or on neighboring cells. Both methods were also used to track single molecules of neurexin, a synaptic adhesion protein, to measure its lateral diffusion in the presence of neuroligin, its trans-synaptic adhesion partner.

Publication ID: 
1423439
Published date: 
21 December 2012
Publication source: 
pubmed
Publication type: 
Journal articles
Journal name: 
ACS Nano
Publication volume: 
6
Publisher: 
Parent title: 
Edition: 
Publication number: